geography essay on drought

ENCYCLOPEDIC ENTRY

Below-average precipitation affects the amount of moisture in soil as well as the amount of water in streams, rivers, lakes, and groundwater.

Earth Science, Climatology, Conservation, Anthropology

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A drought is a period of time when an area or region experiences below-normal precipitation . The lack of adequate precipitation , either rain or snow, can cause reduced soil moisture or groundwater , diminished stream flow, crop damage, and a general water shortage. Droughts are the second-most costly weather events after hurricanes.

Unlike with sudden weather events such as hurricanes, tornadoes, and thunderstorms, it is often difficult to pinpoint when a drought has started or when it has ended. The initial effects of a drought may be difficult to identify right away, so it may take weeks or months to determine that a drought has started. The end of a drought is hard to identify for the same reason. A drought may last for weeks, months, or even years. Sometimes, drought conditions can exist for a decade or more in a region. The longer a drought lasts, the greater the harmful effects it has on people.

Droughts affect people in a several ways. Access to clean drinking water is essential for all life, and sources of water may dwindle during a drought . Without the presence of water, people must bring in enough water from elsewhere to survive. Water is also needed for crops to grow. When not enough precipitation falls to naturally water crops , they must be watered by irrigation . Irrigation is possible only when there is enough water in nearby rivers, lakes, or streams, or from groundwater . During a drought , these water sources are diminished and may even dry up, preventing crops from being irrigated and causing them to die off.

One person studying these problems is Alexandra Cousteau, a National Geographic Emerging Explorer whose latest initiative is Blue Legacy. She started Blue Legacy to raise awareness that we live on a water planet and must take care of it. Cousteau, the granddaughter of the famed ocean explorer Jacques Cousteau, believes that water will be a crucial issue in this century. She predicts that water problems such as drought , storms, floods, and degraded water quality will create “water refugees :” people migrating in search of water. Cousteau stresses that we must do all we can to protect Earth’s valuable freshwater resources.

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What are the causes of drought?

A drought is a severe shortage of water in a particular location. A combination of factors causes droughts.

Meteorological causes of drought

Meteorological factors can cause an area to get less rainfall than average. Changes in global atmospheric circulation can mean it doesn’t rain much in an area. For example, the drought in Australia in the 2000s was made worse by changing air and ocean currents in the Pacific Ocean.

Changes in atmospheric circulation can also affect rainfall patterns. In the past, monsoon rains in India had failed to appear when they were due.

High-pressure systems can block low-pressure systems that bring rainfall to the UK. This can lead to drought conditions.

Hydrological causes of drought

A lack of water in stores such as rivers, lakes, reservoirs and aquifers (water stored underground naturally) can lead to drought. Areas that rely on rainfall and surface water are more likely to experience drought. Surface water quickly evaporates in warm, dry conditions leading to an increased risk of drought.

Hydrological causes of drought can take some time to have an impact. For example, water stores such as aquifers can take months or even years to replenish.

Human causes of drought

Deforestation leads to less water being stored in the soil. Therefore, the land dries out quicker than it would if it were covered in vegetation. Also, trees release moisture into the atmosphere through their leaves, a process is known as transpiration. Removing trees and vegetation reduces the amount of moisture in the atmosphere making the area drier.

Constructing dams and reservoirs reduces the flow of water downstream. This can lead to drought in other areas. There are several locations worldwide where this could lead to conflict in the future, including along the River Nile.

Intensive agriculture depletes water supplies as large quantities of water are required for irrigation . Additionally, livestock also has considerable demands on water for drinking.

Some locations are more vulnerable to drought than others

The map below shows the distribution of droughts around the world.

This map shows drought severity, measured as the product of the average length of a drought occurrence and how dry it was the drought. This visualization is based on data collected for the period between 1901 and 2008.

The areas experiencing the most severe droughts occur at around 30° north and south of the equator. This can be explained by global atmospheric circulation , as high pressure at this latitude brings very little rainfall.

Over time the locations affected by drought have varied. For example, there have been more droughts in Africa, Asia and the Mediterranean since 1950 and fewer in the Americas and Russia.

Some scientists have suggested that climate change might increase the frequency and severity of droughts in the future.

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In This Article Expand or collapse the "in this article" section Drought

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Causes and Drivers of Drought
Global and Continental Drought Climatology
Regional and Local Drought Climatology
Global-Scale Studies
Regional- and Local-Scale Studies
Processes and Methods
Case Studies around the World
Drought Impacts, Mitigation, and Management

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Drought by Woonsup Choi LAST MODIFIED: 25 September 2023 DOI: 10.1093/obo/9780199874002-0215

Drought is a natural disaster that has plagued human society throughout history. However, the meaning of drought varies by perspective and academic discipline, and the cause of drought is difficult to pinpoint. Despite the variation in its meaning, drought generally refers to the condition of an abnormally low amount of water for a given climate. Here the water can be precipitation, streamflow, soil moisture, groundwater, reservoir storage, and the like, but the lack of precipitation is a precursor for other types of drought. The lack of precipitation is often associated with anomalous atmospheric conditions such as atmospheric-circulation anomalies, higher-than-normal temperatures, and lower-than-normal relative humidity. Sea surface temperature anomalies may lead to sustained atmospheric-circulation anomalies. Drought defined as a lack of precipitation is often called meteorological or climatological drought. Other drought types can be classified within the context of the affected sectors, such as agricultural, hydrological, and socioeconomic drought. Agricultural drought generally refers to a lack of soil moisture, and hydrological drought refers to a lack of surface and subsurface water (e.g., streamflow and groundwater). Socioeconomic drought hampers human activities such as industry or water supply. As meteorological drought persists, other types of drought can follow. Such definitions of drought are regarded as conceptual definitions, but operational ones are also necessary for quantitative understanding and management of drought events. Operational definitions use quantitative indices to identify the occurrence and characteristics of drought events such as onset, duration, termination, deficit volume, and spatial extent of drought. Much of existing drought research concerns developing, revising, and applying drought indices to investigate spatial and temporal patterns of drought at various geographical scales. Drought research has progressed along several directions, such as causes and drivers of drought, characteristics of drought events, impacts, and mitigation. Each of these directions is represented by the works cited in this article.

One of the most important issues in drought research is how to conceptualize and define droughts. Cook 2019 , Wilhite and Glantz 1985 , and Mishra and Singh 2010 offer a review of drought concepts, definitions, classification, and indices, and Robeson 2008 reviews research topics in drought that are relevant to applied climatology. There are numerous quantitative indices of drought, and the PDSI (Palmer Drought Severity Index) developed in Palmer 1965 and the SPI (Standardized Precipitation Index) developed in McKee, et al. 1993 are widely used as operational definitions of meteorological drought. The authors of Byun and Wilhite 1999 developed the EDI (Effective Drought Index) while criticizing SPI. Yevyevich 1967 suggests a threshold-level approach to defining hydrological droughts. Van Loon 2015 offers a comprehensive review of hydrological drought, and Van Loon, et al. 2016 reframes the approach to drought with regard to human activities. Tallaksen and van Lanen 2004 collects chapters in various aspects of drought in streamflow and groundwater.

Byun, Hi-Ryong, and Donald A. Wilhite. “Objective Quantification of Drought Severity and Duration.” Journal of Climate 12.9 (1999): 2747–2756.

DOI: 10.1175/1520-0442(1999)012<2747:OQODSA>2.0.CO;2

Discusses major existing drought indices and proposes EDI, which diagnoses meteorological drought by using daily precipitation while giving more weight to recent precipitation than precipitation more distant in the past. An authoritative reference for EDI.

Cook, Benjamin I. Drought: An Interdisciplinary Perspective . New York: Columbia University Press, 2019.

DOI: 10.7312/cook17688

A comprehensive and concise volume that explains drought in various perspectives, including hydroclimatology, climate change, land management, and groundwater. One of the best introductions for those who pursue scientific understanding of drought and good as an undergraduate-level textbook.

McKee, Thomas B., Nolan J. Doesken, and John Kleist. “The Relationship of Drought Frequency and Duration to Time Scales.” Proceedings of the 8th Conference on Applied Climatology 7.22 (1993): 179–183.

Defines drought on the basis of standardized precipitation, which is the difference between precipitation for a particular period and the mean divided by the standard deviation. The mean and standard deviation are determined from historical data. The standardized precipitation is expressed as SPI for varying lengths; for example, one month (SPI-1), three months (SPI-3), twelve months (SPI-12), etc. A common reference for SPI.

Mishra, Ashok K., and Vijay P. Singh. “A Review of Drought Concepts.” Journal of Hydrology 391.1–2 (2010): 202–216.

DOI: 10.1016/j.jhydrol.2010.07.012

Reviews a wide range of issues related to drought, including need for drought research, drought definitions and classification, drought indices, and relationship between drought and large-scale climate indices. One of the best introductions for those who pursue scientific understanding of drought.

Palmer, Wayne C. Meteorological Drought . Washington, DC: US Department of Commerce, 1965.

An authoritative reference for PDSI. Defines drought severity and duration, considering water balance components as well as precipitation. The PDSI numbers are classified by levels of dryness and wetness.

Robeson, Scott M. “Applied Climatology: Drought.” Progress in Physical Geography 32.3 (2008): 303–309.

DOI: 10.1177/0309133308091951

Reviews major research fields in drought from an applied-climatology perspective, focused on monitoring, climate change impacts, and modeling.

Tallaksen, Lena M., and Henny A. J. van Lanen, eds. Hydrological Drought: Processes and Estimation Methods for Streamflow and Groundwater . Amsterdam: Elsevier, 2004.

A collection of chapters addressing drought in streamflow and groundwater. Chapters about the science or management of drought are adequate for entry-level graduate students, but those about drought estimation methods are highly technical.

Van Loon, Anne F. “Hydrological Drought Explained.” Wiley Interdisciplinary Reviews: Water 2.4 (2015): 359–392.

DOI: 10.1002/wat2.1085

Provides a comprehensive review of hydrological drought, including typology and indices and discusses research gaps and challenges.

Van Loon, Anne F., Kerstin Stahl, Giuliano Di Baldassarre, et al. “Drought in a Human-Modified World: Reframing Drought Definitions, Understanding, and Analysis Approaches.” Hydrology and Earth System Sciences 20.9 (2016): 3631–3650.

DOI: 10.5194/hess-20–3631–2016

Emphasizes the impact of humans on drought, particularly hydrological drought, and reframes the way that drought is defined and analyzed in the Anthropocene. Clarifies drought terminology and identifies research gaps in drivers, modifiers, impacts, feedbacks, and baselines of drought.

Wilhite, Donald A., and Michael H. Glantz. “Understanding the Drought Phenomenon: The Role of Definitions.” Water International 10.3 (1985): 111–120.

DOI: 10.1080/02508068508686328

Provides detailed discussion of drought definitions. Suggests subdividing the definitions into four types on the basis of disciplinary perspectives (meteorological, agricultural, hydrological, and socioeconomic), and such a classification has been widely adopted in the literature, including the review in Mishra and Singh 2010 .

Yevyevich, Vujica M. “ An Objective Approach to Definitions and Investigations of Continental Hydrologic Droughts .” Hydrology Papers, Colorado State University 23 (1967).

Suggests an “objective” definition of hydrological droughts at continental or large-area scales. It is regarded as the first work that defined droughts by using runs of the sequence of a variable, where droughts are defined in terms of duration, deficit volume, and intensity. Most papers investigating hydrological droughts cite this paper.

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[66.249.64.20|185.66.15.189]
185.66.15.189

In recent years, California experienced a historic drought, forcing many farmers to fallow their fields. New research helps link such disasters to a warming planet.

ENVIRONMENT

Climate change has contributed to droughts since 1900—and may get worse

A first-of-its-kind study confirms the connection between climate change and droughts and deluges over the past century.

Using studies of tree rings going back centuries, scientists have unearthed clear evidence that the rise of human-generated greenhouse gases was having an effect on global drought conditions as early as 1900.

A new, first-of-its-kind study by scientists at Columbia University’s Earth Institute , published Wednesday in the journal Nature , largely confirms what climate models have shown. In the absence of strong historic data on precipitation, those computer models forecast not only future scenarios, but shed light on historical trends.

The dovetailing of the tree-ring studies, which correlate to soil moisture, with climate models gives scientists the assurance that the computer models are, in fact, correct, they say.

“These tree-ring reconstructions let us go back in time and get a picture of global drought conditions for hundreds of years before the Industrial Revolution,” said Kate Marvel , an associate research scientist at the Earth Institute and NASA's Goddard Institute for Space Studies and the lead author of the study.

Marvel said that the results, while not unexpected, are nonetheless gratifying. “As a scientist, you are always surprised whenever anything you do works,” she said in a phone interview. “There were increased greenhouse gases in the early 1900s and the models say, ‘Hey, you should see a signal.’ But the fact that the signal is really clear in the models and apparent in the tree rings is pretty amazing. We can argue for a detectable human influence.”

Fingerprinting droughts

Scientists have long predicted that as global warming increases, certain regions of the world, such as the southwestern United States , will become drier, while other areas will grow wetter. But the Intergovernmental Panel on Climate Change has cautioned against ascribing particular rain or drought events to human activity.

The tree-ring data analyzed in the study highlight three periods over the past 120 years in which a human fingerprint on drought and moisture is, to varying degrees, evident. The first, from 1900 to 1949, reveals the strongest signal, mirroring climate models showing that parts of the world from Australia to the Mediterranean were drying as other regions, including swaths of central Asia, were moving in the opposite direction.

The next period, from 1950 to 1975, is more murky, though the tree rings again match the climate models. The study posits that aerosols —particles from car exhaust and the burning of fossil fuels—were so abundant before the advent of anti-pollution measures that they served to block sunlight and thus cool the planet, even while tracking the uptick in greenhouse gases.

The last period, from 1981 to 2017, saw a reappearance of the human influence on drought and moisture. The study concludes that this signal is “likely to grow stronger in the next several decades,” adding that the “human consequences of this, particularly drying over large parts of North America and Eurasia, are likely to be severe.”

The study relied on a series of drought atlases containing tree-ring data from around the globe over the past two millennia. The atlases were assembled primarily by Edward Cook , a scientist at Columbia’s Lamont-Doherty Earth Observatory and the father of Benjamin Cook, one of the study’s co-authors.

Trees respond

Gregory R. Quetin , a postdoctoral researcher in Stanford’s Department of Earth System Sciences, who was not involved in the study, called the findings “powerful,” pointing to the climate record encoded in the tree rings.

“The trees are responding to temperature and the presence of, or lack of, rainfall,” he said, “so they give you these observations—and another path of evidence that this is occurring.”

Abigail Swann , an atmospheric scientist at the University of Washington, agreed: “It’s a creative way to leverage that information from the past.”

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Drought Essay

500 words essay on drought.

Droughts refer to conditions when particular regions face scarcity of water because of low or no rainfall. It is one of the most prevalent problems in India. A lot of areas in the country get hit by drought every year while others face it occasionally. Moreover, many factors contribute to the problem of drought which includes deforestation, global warming and more. Drought essay will take us through it in detail.

Drought Prone Areas in India

In India, there are a lot of chronic drought-affected regions. They include the West Rajasthan and the Kutchtch regions of Gujarat. The main factor for this is the geographical location of these areas.

Moreover, the monsoon season in this area is also very weak by the time they reach there. In addition, humans degrading the environment also do not help but add to the brutality of this problem.

Other than that, other drought-prone areas are Western Orissa, Rayalsema and Telangana areas of Andhra Pradesh, Jharkhand, interior Karnataka, Chhattisgarh and more. However, the two states which suffer the most from both floods and drought are Uttar Pradesh and Bihar.

As per an estimate, around 70% of cultivable land in India is Drought prone. If we look at the past three years, some areas in Rajasthan have been experiencing very little rains. Thus, it becomes harder for the people in that area.

The most impacted section of the society is the marginal farmers, landless labourers and persons from the economically backward section. In addition, the tribal depending on forest produce also suffer from droughts.

Prevention of Droughts

With droughts, the case is different from tsunamis and cyclones. Meaning to say, we can predict it much in advance. Thus, it gives ample time for the Government authorities to prepare for it in advance and cope with this problem.

The Meteorological Department can easily predict the quantity and duration of rainfall with a fair degree of accuracy. As a result, we can counter the intensity and impact of droughts by a series of preventive as well as curative measures.

First of all, we must promote small scale and cottage industry in order to reduce the dependence on agriculture in drought-prone areas. Further, executing a rainwater harvesting project with community cooperation can help in many areas.

Most importantly, we must increase the forest cover by plantation. Similarly, we can also research arid cultivation technologies to implement them in drought-prone areas.

It is also essential to formulate drought management strategies with the involvement of the communities. Finally, we must also introduce crop insurance schemes so that the farmers do not suffer a great loss.

Get the huge list of more than 500 Essay Topics and Ideas

Conclusion of Drought Essay

To sum it up, drought is a difficult situation with which we have to deal with. When the severity is high, it becomes all the more difficult to manage it. A lot of people get affected because of droughts every year as it reduces human activities. Thus, it is essential to take effective measures to deal with it.

FAQ of Drought Essay

Question 1: What are the effects of drought?

Answer 1: Drought affects the environment in a lot of different ways. We all know that plants and animals depend on water, just like humans. When a drought happens, their food supply shrinks and their habitat can be damaged. As a result, an increase in disease in wild animals happens because of reduced food and water supplies.

Question 2: Why do droughts happen?

Answer 2: Droughts happen when there is not enough rain for a long period of time. It is not like a dry spell, there is so little precipitation (rain, snow, sleet ) that a whole province starts to dry out. Sometimes, a drought can take decades to fully develop.

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Drought in the Eastern Cape region of South Africa and trends in rainfall characteristics

Published: 14 August 2020
Volume 55 , pages 2743–2759, ( 2020 )

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P. T. Mahlalela 1 ,
R. C. Blamey 1 ,
N. C. G. Hart 2 &
C. J. C. Reason ORCID: orcid.org/0000-0002-3224-5243 1

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Much of the Eastern Cape province in South Africa has been experiencing a severe drought since 2015. This drought has had major socio-economic effects particularly on the large impoverished rural population as well as on some urban areas where supplied water services have broken down in several cases. The region is influenced by both midlatitude and tropical systems leading to a complex regional meteorology that hitherto has not been much studied compared to other parts of South Africa. Here, the ongoing drought is examined in the context of long-term trends and the interannual rainfall variability of the region. Although the region has experienced drought in all seasons since 2015, focus here is placed on the spring (September–November) which shows the most consistent and robust signal. On average, this season contributes between about 25–35% of the annual rainfall total. Based on CHIRPS data, it is found that this season shows a significant decreasing trend in both rainfall totals as well as the number of rainfall days (but not heavy rainfall days) for spring over most of the province since 1981. On interannual time scales, the results indicate that dry (wet) springs over the Eastern Cape are associated with a cyclonic (anticyclonic) anomaly southeast of South Africa as part of a shift in the zonal wavenumber 3 pattern in the midlatitudes. Over the landmass, a stronger (weaker) Botswana High is also apparent with increased (decreased) subsidence over and near the Eastern Cape which is less (more) favourable for cloud band development and hence reduced (enhanced) rainfall during dry (wet) springs. Analysis of mid-century (2040–2060) CMIP5 rainfall projections suggests that there may be a flattening of the annual cycle over the Eastern Cape with the winter becoming wetter and the summer drier. For the spring season of interest here, the multi-model projections also indicate drying but less pronounced than that projected for the summer.

Projected changes of compound droughts and heatwaves in China under 1.5 °C, 2 °C, and 3 °C of global warming

Taizheng Liu, Yuqing Zhang, … Jing Ge

RETRACTED ARTICLE: A critical assessment of extreme events trends in times of global warming

Gianluca Alimonti, Luigi Mariani, … Renato Angelo Ricci

Avoid common mistakes on your manuscript.

1 Introduction

South Africa is facing severe pressure with respect to water security due to an increased water demand with increasing population, poor planning and management of water resources, limited investment into water reservoir infrastructure, and recurring droughts over the past decade. Although droughts often happen in South Africa, in recent decades there has been a tendency for more multi-year droughts to occur. For example, summer rainfall time series for various parts of South Africa, including the Eastern Cape and adjoining KwaZulu Natal Province show more multi-year droughts during late 1970s to 2017 than during 1950-late 1970s (Fig. 5 of Blamey et al. 2018a ). In February 2018, the Western Cape Province was declared a disaster area after a severe drought which occurred between 2015 and 2018 (Pienaar and Boonzaaier 2018 ; Sousa et al. 2018 ; Mahlalela et al. 2019 ; Burls et al. 2019 ). In October 2019, the Eastern Cape Province (see Fig. 1 for its location in South Africa) was declared a drought disaster region following pronounced water shortages in many urban and rural areas.

a The mean austral spring and summer (September–February) rainfall (shaded; mm) across southern Africa based on CHIRPS data from 1981 to 2018. b A zoomed in version of the mean spring and summer rainfall for the southeast region of the domain. The green polygon in both panels illustrates the location of the Eastern Cape Province in South Africa. Also shown in panel b are the locations of the South African Weather Service rain-gauges used in the study

The Eastern Cape is of interest not just because of the severe drought that it is currently experiencing but also because its western parts lie near the transition zone between the summer (most of southern Africa) and winter rainfall regions (southwestern South Africa, Reason et al. 2002 ; Blamey et al. 2018b ) and because it is a region of sharp vegetation, soil moisture and topographic gradients (Fig. 2 a). As a result, the meteorology here is complex and often involves interactions with the regional topography or the neighbouring warm Agulhas Current (e.g., Rouault et al. 2002 ; Singleton and Reason 2006 ). It was argued by Jury et al. ( 1993 ) that the distance from the Eastern Cape coast to the core of this current which is of order a few 10 s of kms north of 33° S but of order 100 km by the time the current reaches 34° S, may play a role in the strong decrease in mean rainfall along the Eastern Cape coast (see Fig. 1 b). The coast near Port Elizabeth at 34° S is relatively dry as is the western interior which forms part of the Karoo semidesert of the central-western inland regions of South Africa. The western coast of the Eastern Cape merges into the small all-season rainfall region that extends along the south coast of South Africa between about 22–25° E (Weldon and Reason 2014 ; Engelbrecht et al. 2015 ). From about East London (~ 28° E, 33° S) northwards, the coastal regions are much wetter as are the northeastern inland regions of the Eastern Cape near the Drakensberg and Maluti mountains (Lesotho). Figure 1 shows the rainfall gradients and totals across the Eastern Cape during the spring and summer in relation to those that exist across the rest of southern Africa (summer rainfall dominated everywhere except for western South Africa and the south coast of South Africa) .

Panel a illustrates the topography (shaded; m) of the domain along with the various rivers and river basins. The river basins have been merged into a “west” and “east” basin to highlight some of the regional rainfall differences. Also shown are the locations of the main dams of the region that have seen large water level drops as well as locations of the main towns/cities. Panel b shows the smoothed monthly dam levels (given in % stored) from around 1981 until 2018, while panel c shows the austral summer rainfall standardized anomalies, based on CHIRPS, for the regions defined as west and east basin in panel a

Precipitation over the Eastern Cape region is influenced by weather systems from both the tropics and midlatitudes, ranging from small-scale convective storms to synoptic-scale tropical-extratropical cloud bands (known locally as tropical-temperate troughs—TTTs). These cloud bands are the major synoptic rainfall producing system over subtropical southern Africa during the early to mid-summer (Harrison 1984 ; Diab et al. 1991 ; Todd and Washington 1999 ; Hart et al. 2010 ; Manhique et al. 2011 ). Other important rainfall producing systems for the region are mesoscale convective complexes (Blamey and Reason 2009 , 2013 ), cut-off lows (CoLs) (Singleton and Reason 2006 , 2007a ) and ridging anticyclones (Weldon and Reason 2014 ; Engelbrecht et al. 2015 ; Engelbrecht and Landman 2016 ).

Also shown in Fig. 2 a are the catchment areas of the main dams supplying the province’s largest municipality (Nelson Mandela Bay) which contains the major coastal city of Port Elizabeth (located near 34° S) (termed the “west” basin) as well as those for rivers draining the wetter northeastern part of the province (termed the “east” basin). The impact of the current drought can be seen in the levels (Fig. 2 b) of two of the larger supply dams (Impofu and Kouga). After being close to full in 2015, both dams have fallen to their lowest levels since 1985 with the decline during 2017–2019 being especially sharp. As of June 2020, the Kouga dam sits at 7% with the combined supply dam capacity for the Nelson Mandela Bay metro having fallen below 20%. Several other major towns in the province (Grahamstown, Graaff-Reinet, Bedford and Queenstown) have also been experiencing very severe water shortages. The ongoing drought has already cost the province over R120 million for drought relief measures. Due to the increased threat to water security in the Eastern Cape and more broadly, South Africa as whole, understanding the variability and trends in rainfall features that influence water availability over this region is of crucial importance for effective management and planning. Furthermore, relatively little work has been done on the climate of the Eastern Cape region compared to other parts of South Africa despite it being an important agricultural part of the country with a sizeable rural population. The region is also one of the least developed of South Africa’s nine provinces with many impoverished rural settlements which are particularly vulnerable to drought and severe weather events. It has also been impacted severely by the COVID-19 crisis with almost 20% of South Africa’s total of ~ 400,000 cases by late July 2020 as compared to having less than 12% of the national population.

Here, focus is placed on the spring season (September–November SON) which seems to show the strongest and most consistent drought signal since 2015. As discussed below, SON contributes between 25 and 35% of the annual rainfall over the Eastern Cape on average. Furthermore, given its importance for agriculture (fruit, dairy and angora goats are the main exports), severe drought is highly problematic at this time of year when solar insolation, ground temperatures and potential evapotranspiration are also increasing. Thus, the aims of the study are to investigate the post-2015 drought within the context of previous large anomalies in spring rainfall over the last forty years and any long-term rainfall change and to examine the potential mechanisms associated with spring drought in the region.

2 Data and methods

Daily rainfall data over the Eastern Cape were provided by the South African Weather Service (SAWS) for January 1981–December 2018 for comparison against daily gridded data (CHIRPS). Only stations with 90% data available for the full period were included in the analysis, and for which the station location has stayed more or less the same. The locations of 11 weather stations used in this study are shown in Fig. 1 b. Due to the restricted spatial coverage of the available SAWS rain gauges, Climate Hazards Infrared Precipitation with Stations (CHIRPS) daily data were used to consider spatial variability of rainfall variability and trends across the Eastern Cape. CHIRPS is a merge of different products including satellite imagery and station values available at 0.05° (5 km) spatial resolution on a quasi-global (50° S–50° N) grid, for the period 1980 to present (Funk et al. 2015 ). A correlation analysis was done between CHIRPS and station data to assess confidence in the ability of CHIRPS to represent the region.

Daily rainfall data were converted to seasonal totals with Fig. 3 showing the seasonal rainfall climatology across the Eastern Cape. It is clear that spring (SON) and summer (DJF) contribute most of the annual rainfall on average for the bulk of the province. For the coastal zone, spring and summer each contribute about 30% of the annual total whereas summer dominates in the northern interior (40–45%). The autumn accounts for about 20–25% over most of the province with a small region in the far west reaching 30% whereas for winter, only in the far south, does rainfall in this season reach 15% of the annual total on average. Here, focus is placed on SON which seems to show the strongest and most coherent drought signal. However, the extended summer (September–April) is also considered when determining anomalously wet and dry seasons for composite analysis of the interannual variability in the seasonal rainfall totals. These anomalously wet (dry) SON seasons were chosen such that they occur in the same year as the overall (SONDJFMA) summer being wet (dry).

The mean seasonal rainfall contribution (shaded with contours; in percentage) to the annual rainfall total for a winter—JJA, b spring—SON, c summer—DJF and d autumn—MAM

Compositing of fields from the NCEP-DOE II reanalysis data (Kanamitsu et al. 2002 ), at a spatial resolution of 2.5°, are used to examine the circulation anomalies associated with anomalously dry and wet seasons during the study period. Moisture fluxes were computed from the product of the horizontal wind and the specific humidity at the level of interest. NCEP II reanalyses are also used to plot features of semi-permanent anticyclones in the Indian and Atlantic Oceans. For the purpose of this study, the northern, southern, eastern and western extension of the anticyclones is determined as the outer boundary of the 1020 hPa contour in the mean sea level pressure field (MSLP). This contour level is chosen as it is easily identified as closed contour level around the anticyclones, which is not intersected with the neighbouring land masses in either the early or late summer periods. The latitude and longitude of the centre of the South Indian Ocean High is defined here as the location with the maximum in the MSLP field (after applying a spatial smoothing filter) within the climatological mean area (40°–110° E; 15°–40° S).

Trends in various seasonal rainfall characteristics such as the number of rainy days (daily rain > 1 mm) and heavy rainfall days (daily rain > 10 mm) were evaluated using a non-parametric Mann–Kendall test over the analysis period 1981–2018. This test was used as it makes no assumption about the data distribution and is insensitive to outliers. The magnitude of the trend is calculated using the Sen’s slope estimator. This method uses the median of all possible slopes for the given series making it statistically robust. The probability of the trend occurring was measured at a 5% significance level.

To see whether some insight may be obtained about future rainfall scenarios, a topic of great interest to both the public and the government, future rainfall projections in the region are considered using 36 models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) ensemble (Taylor et al. 2012 ). A 21 year mid-twenty-first century future period (2040–2060), under the high energy intensive scenario, Representative Concentration Pathway (RCP) 8.5, was chosen. Only one ensemble member (r1i1p1) per model is included in the analysis. For ease of comparison, precipitation (atmosphere variables) in the models are re-gridded using bilinear interpolation to a common 1.5° × 1.5° (2.5° × 2.5°) grid. Rainfall from the models is compared with satellite-based estimates from the Global Precipitation Climatology Project (GPCP) monthly precipitation data set (Adler et al. 2003 ) and Climate Prediction Center Merged Analysis of Precipitation (CMAP) (Xie and Arkin 1997 ).

3 Spring rainfall variability

3.1 rainfall means and trends.

Figure 4 plots standardized anomalies of SON rainfall for the period 1981–2018 for the 11 available SAWS stations together with CHIRPS data averaged from the 4 grid points surrounding each station (small red boxes in Fig. 1 b). Note that the annual cycle from the two datasets is the same for each case (not shown). The time series are correlated at 95% significance at each station with r values ranging from 0.61 to 0.90. Note that it is possible that topographic effects or other local forcing may lead to the differences between the time series. Although the sign of the anomalies is almost always the same for each station, there are some springs when there are sizeable differences in magnitude at some stations. However, the correspondence between the two time series during the almost 40 year period at both coastal and inland stations provides sufficient confidence in the ability of the CHIRPS data to adequately represent rainfall variability and change across the province. All of the stations except the two western near-coastal locations (Joubertina and Humewood) show a decreasing tendency in spring rainfall but only the negative trends at Dohne and Philadelphia are statistically significant.

Spring (SON) standardised anomalies for the eleven stations (grey-dashed line) across Eastern Cape (see Fig. 1 b) and the corresponding CHIRPS (black-solid line) anomalies. The station names are indicated at the top of each panel. The correlation between the two datasets is given at the bottom left of each panel. The trend in SON rainfall for each station is given the bottom right hand corner of the panel (in mm per decade). For both the correlation and the trend analyses, the asterisk denotes significance at the 95% level using a Student t-test

Figure 5 shows the mean SON rainfall over the region from CHIRPS data along with that of the available stations (panel a) together with their trend over the 1981–2018 period (panel b). Most of the region shows a statistically significant decline in spring rainfall, particularly in the east, north and northeast. The weak decrease near Port Elizabeth is not significant but part of the catchment areas in the “west” basin to the north and northwest of this city are. Given that the decrease is much stronger in the wetter eastern half of the province, the results imply that the rainfall gradient across the province (Fig. 5 a) is weakening, at least in spring. The stronger decrease in the east is concerning given the larger rural population here and its greater importance for agriculture to the provincial economy (particularly dairy, pineapples and tea).

a The mean SON rainfall in CHIRPS (shaded; mm) and SAWS stations (circles; mm) and b the corresponding trend in SON rainfall over the period 1981–2018. Stippling or larger circles denotes values significant at a 95% level using a two-tailed Mann–Kendall test

Maps of the number of rain days (> 1 mm per day), heavy rain days (> 10 mm per day) and their trend across the province are plotted in Fig. 6 using CHIRPS data. A contrast exists between fewer (more) rain days in the west/southwest (northeast) consistent with rainfall totals being of order 50–150 mm in the former and 250–400 mm in the latter region (Figs. 5 a, 6 a). There is less of a contrast in the distribution of heavy rainfall days across the province with only the north coast showing a much greater frequency than the south (Fig. 6 c). In terms of trends (Fig. 6 b, d), the strongest negative trends are again in the north and northeast with that in rain days making a more obvious contribution to the rainfall total decreasing trends (Fig. 5 b) than that in heavy rain days. In the far west, it is notable that the area of significant decrease in both rain and heavy rain days represents part of the Kouga and Impofu dam catchment areas in the “west” basin that feed into the Port Elizabeth urban area.

a The climatological number of rain days in SON (daily rain ≥ 1 mm) over the Eastern Cape Province and b the trend in the SON rain days (given as days per decade) in CHIRPS data and SAWS stations (circles) over the period 1981–2018. c , d , same as a , b but for rain days ≥ 10 mm. Stippling (green or black) or larger circles denotes values significant at a 95% level using a two-tailed Mann–Kendall test

In terms of the recent period, all stations (Fig. 4 ) show average to well below average rainfall during SON 2015 with several also showing that a sharp decline occurred in this season with little or no recovery during 2016–2018. Only Willowmore appears to show average rainfall by SON 2018 whereas the partial recovery at the other two westernmost stations (Humewood and Joubertina) in 2017 is then followed by more negative rainfall anomalies in 2018. Examination of GPCC data (not shown) indicates that most of South Africa including the entire Eastern Cape received below average rainfall in SON 2019. Although a run of several years of below average rainfall is not uncommon in spring (Fig. 4 ), or indeed in summer (Blamey et al. 2018a ), in the Eastern Cape, it is clear that most of the consecutive years of dry springs have occurred in the most recent decade whereas most of the well above average rainfall springs occurred between 1981–2005. This run of recent consecutive dry springs is consistent with the trend results (Figs. 5 , 6 ) and implies that the sharp decline at most stations since 2015, with little recovery in rainfall since, has led to the recent drought having more devastating impacts than would otherwise be the case due to depletion of surface and groundwater resources over a long period. Furthermore, spatial maps (not shown) of CHIRPS rainfall anomalies across the region for spring show that the last significantly wet season (spatially averaged standardised anomaly of 1.35) occurred in 2001 with only three of the springs between 2003 and 2018 showing positive anomalies (0.18 in 2006, 0.26 in 2007 and 0.09 in 2014). The remaining springs are all dry to very dry except for 2005 (− 0.01) with the recent springs of 2016 and 2018 showing anomalies of − 1.11 and − 0.84, respectively.

Based on springs that were followed by summers of the same signed anomaly, then the following seasons were respectively defined as significantly dry (1981, 1990, 1994, 2008, 2016) or wet (1985, 1989, 1993, 1996, 2001) (Table 1 ). Even with this stricter criterion of the extended summer “half” of the year (September–April) being anomalously dry or wet, it is evident that all of the latter occurred in the first two decades of the period. The dry seasons are more evenly spread out although 2 of the 5 occurred in the last decade. However, if the criterion about the subsequent summer is relaxed, then the wet springs remain the same but the dry seasons are slightly changed (1990, 1994, 2011, 2016, 2018) with now 3 of the 5 in the last decade. To examine potential mechanisms associated with these anomalous seasons, the next section considers composites of various circulation fields.

3.2 Interannual variability: potential mechanisms

To assess potential mechanisms associated with the interannual rainfall anomalies, composites of 500 hPa geopotential height and omega, 850 hPa moisture flux and divergence, and OLR are analysed for the spring seasons in Table 1 . Figure 7 shows that dry (wet) springs over the Eastern Cape are associated with a cyclonic (anticyclonic) anomaly to the southeast of South Africa which is part of a wavenumber 3 or 4 pattern in the Southern Hemisphere midlatitudes. Further north over Namibia, Botswana and Angola there are positive (negative) anomalies implying a stronger (weaker) mid-level Botswana High which has been previously associated with drier (wetter) conditions over subtropical southern Africa in late summer (Reason 2016 ; Driver and Reason 2017 ). The cyclonic (anticyclonic) anomaly southeast of South Africa is also evident at lower levels leading to an enhancement (reduction) in offshore dry flow (Fig. 8 b, c) relative to the 850 hPa climatological moisture flux (Fig. 8 a) in the dry (wet) springs. There is relative divergence (convergence) of this low-level moisture over the neighbouring Agulhas Current unfavourable for the strengthening (weakening) of rain-producing weather systems in the region such as ridging anticyclones, cold fronts and cloud bands. SST composites (not shown) indicate cool (warm) anomalies in the greater Agulhas Current region which have previously been associated with dry (wet) summers over eastern South Africa (e.g., Walker 1990 ; Mason 1995 ; Reason and Mulenga 1999 ; Reason 1999 ). The omega anomalies (Fig. 9 a, b) support this suggestion of changes in the strength of weather systems over the Eastern Cape with strong relative subsidence (uplift) over most of the Eastern Cape as well as much of South Africa and the ocean to the south of the country in the dry (wet) composite. The northwest-southeast orientation of the omega anomalies across western southern Africa suggests unfavourable (favourable) conditions for cloud band development during the dry (wet) springs. Using the met-bot cloud band tracking methodology developed by Hart et al ( 2012 ), it is found that there are indeed about 1–2 less (more) cloud band days than average during the dry (wet) springs over much of South Africa, including most of the Eastern Cape. Also evident in Fig. 8 b, c is a weakening (strengthening) of the Angola Low and relative offshore (onshore) moisture flow from the tropical South East Atlantic. A stronger Angola Low and this moisture inflow have been found to be important for both synoptic and seasonal scale wet spells in summer over South Africa and the reverse during dry conditions (Mulenga et al. 2003 ; Cook et al. 2004 ) since it often acts as the source region for cloud bands. Figure 10 shows the corresponding OLR composite anomalies again revealing a northwest–southeast orientation which is consistent with less (more) cloud bands/other convective systems and hence decreased (increased) rainfall over the Eastern Cape during the dry (wet) spring seasons.

SON geopotential height composite anomaly (shaded with contours; m) at the 500 hPa level for a dry and b wet springs

a The mean moisture flux divergence (shaded; g kg −1 s −1 × 10 –5 ) and moisture flux (scale vector shown) during SON at the 850 hPa level. Panels b , c show the composite anomalies for dry and wet springs respectively (shaded; g kg −1 s −1 × 10 –6 )

SON composite anomaly of omega (shaded with contours; Pa s −1 ) at the 500 hPa level for a dry and b wet springs

Composite anomaly of OLR (shaded; W/m −2 ) for a wet and b dry springs

It is unclear as to whether these circulation patterns for the anomalous springs are related to any of the large-scale climate modes that are known to directly affect rainfall over subtropical southern Africa. Indeed none of the hemispheric circulation anomalies in Fig. 7 are obviously reminiscent of these climate modes which are ENSO, the South Indian Ocean subtropical dipole (SIOD), the Benguela Niño, and the Southern Annular Mode (SAM). All of these have strong seasonality to their impacts on regional rainfall over subtropical southern Africa with the first two being important in mid-late summer (December–March) (Lindesay 1988 ; Mason 1995 ; Reason et al. 2000 ; Behera and Yamagata 2001 ; Reason 2001 ), the third in the late summer and typically more over Namibia and Angola than South Africa (Rouault et al. 2003 ; Hansingo and Reason 2009 ) while SAM impacts have been found in summer (Gillett et al. 2006 ) over much of the region and over western South Africa in winter (Reason and Rouault 2005 ). Indeed, correlations of Niño 3.4, the Benguela Niño, the SIOD index (Behera and Yamagata 2001 ) or the SAM index (Marshall 2003 ) do not show any significant or coherent signal over the Eastern Cape in spring. Correlations of the spring Eastern Cape rainfall with the Indian Ocean Dipole (DMI) (Saji et al. 1999 ) which manifests in spring (and is strongly correlated with equatorial East African rainfall) show a negative correlation over the Eastern Cape but it is not statistically significant. For summer, only the SAM index shows a coherent and statistically significant correlation (positive in sense) over the Eastern Cape region (not shown). This lack of consistency of climate signals in not just spring but also in summer (except for SAM) further adds to the challenge of trying to understand the climate variability of this complex region. Because the Eastern Cape includes the transition zone between the winter and summer rainfall dominated regions of South Africa, even small changes in the ways that individual ENSO, SIOD, IOD or SAM events influence the tracks or strengths of rain-producing weather systems crossing the region can have substantial impacts on seasonal rainfall and may preclude any consistent signal.

Although there does not appear to any obvious linkage between these large-scale climate modes and spring rainfall over the Eastern Cape, the wavenumber 3 or 4 patterns in Fig. 7 suggest that changes in the South Atlantic or South Indian Ocean semi-permanent anticyclones might be important. On average during spring, the former anticyclone tends to move southeastward towards southwestern South Africa, signalling the end of the winter rainy season there. The South Indian Ocean High (SIHP) also tends to retreat southeastwards in spring and the continental high over southern Africa breaks down then, coincident with the end of the dry winter half of the year for southern Africa (except the far southwest). On examining the spatial extent and centre of these anticyclones for the composite seasons, it is found that the South Atlantic anticyclone tends to be located further to the southeast (and closer to western South Africa) in drier than wetter springs while the SIHP tends to located nearer Western Australia (eastern South Africa) in the dry (wet) case. These anomalous locations of the anticyclones further encourage less (more) cloud bands and cold fronts over the Eastern Cape region during dry (wet) springs.

For the SIHP, its eastern extent (Fig. 11 a) is strongly negatively correlated with SON rainfall over the “west” basin of the Eastern Cape as well as most of western South Africa. The “west” basin also shows a significant negative correlation with the northern extent of the SIHP (Fig. 11 d). Based on the climatological moisture flux shown in Fig. 8 a, this negative correlation might be related to a more northward extending SIHP leading to a reduced easterly moisture flux into northern South Africa, Zimbabwe and Mozambique and subsequent weaker northerly moisture inflow towards the Eastern Cape and thus drier conditions. It is not obvious that a more eastward extending SIHP could also lead to a negative correlation with rainfall but a possibility is that this location of the SIHP tends to favour cloud bands being located more over the South West Indian Ocean rather than over the landmass (Fauchereau et al. 2009 ; Hart et al. 2018 ). The southern and western extents of the SIHP (Fig. 11 b, c) are also mainly negatively correlated with Eastern Cape SON rainfall but this is only statistically significant for small areas in the far northeast near Lesotho.

The correlation between SON rainfall and a eastern, b southern, c western and d northern extent of the South Indian Ocean High Pressure (see text for details). Areas that are statistically significant at the 95% level are denoted by stippling. The location of the Eastern Cape river basins is denoted with the black polygon

Although Fig. 7 indicated shifts in wavenumber 3 pattern, it can be seen that only the circulation anomaly in the midlatitude South Indian Ocean is consistent between the dry and wet spring composites since the anomalies in the midlatitude South Pacific and South Atlantic are not exactly in the same place. Nevertheless, using a zonal wavenumber 3 index such as that proposed by Raphael ( 2004 ) leads to a fairly strong and statistically significant correlation (Fig. 12 a) with spring rainfall over much of the Eastern Cape as well as part of the northeast of South Africa. If an index for only the South Indian Ocean component of the wavenumber 3 index is used (standardised anomalies in 500 hPa geopotential height spatially averaged over 45–50° S, 45–60° E) then Fig. 12 b indicates a statistically significant correlation over the central third of the Eastern Cape (with stronger r values than for the full index) as well as some other parts of subtropical southern Africa in a NW–SE cloud band type orientation.

The correlation between SON rainfall and a the zonal wave number 3 index of Raphael ( 2004 ) and b only the South Indian Ocean High component of that index. Areas that are statistically significant at the 95% level are denoted by stippling. The location of the Eastern Cape river basins is denoted with the black polygon

3.3 Model rainfall projections

Given the trends in spring rainfall and rain days (Figs. 4 , 5 , 6 ) over the Eastern Cape and the great concern of the public and government about climate change, it is of interest to examine CMIP5 model projections for future rainfall over the region, particularly since there is a likelihood of more extreme rainfall events occurring over southern Africa in the future (IPCC 2013 ). As already seen in Fig. 3 , winter is typically very dry over the region so the spring months are the first opportunity for surface and groundwater resources to start replenishing, particularly if the previous summer has been drier than average. Thus, it is of concern to know whether climate models are projecting that these spring months might become drier in future and how well the models can represent the annual cycle in rainfall.

Figure 13 a plots the annual cycle of rainfall over the Eastern Cape for 36 CMIP5 models and for two observed gridded rainfall products that have similar resolution to the models (GPCP and CMAP). The latter show a weak bimodal cycle with November and February as the wettest months; however, the bimodal aspects in the dry season are not obvious since May, June and July are all very similar and then the average rainfall starts increasing from August. This bimodal cycle is a weaker version of that evident in Southern Hemisphere regions (and related to the semiannual oscillation) which are located more in the mid-latitudes such as southern Victoria, Australia which extends to 38° S as compared to the Eastern Cape which lies north of 33–34° S. Almost all the models show a much wetter summer half of the year than winter but only some show February or November as the wettest months. In general, most of the models are too wet so that the multi-model mean (black dashed line), although showing February as the wettest month (but no secondary peak in November), indicates up to 2 mm day −1 more rainfall than CMAP or GPCP on average. However during spring, the wet bias is smaller (1 mm day −1 ) with November being the wettest month as observed; the lack of a small decrease from November to December in the multi-model mean unlike in the observed is not directly relevant to the spring focus in this study.

The annual cycle of rainfall (rain rate; mm/day) averaged across the river basin polygon for the Eastern Cape in 36 CMIP5 models for a the historical runs for the 1979–2005, b the mid-twenty-first century projections (2040–2060) and c the difference between the mid-twenty-first century projections and the historical runs. For comparison, two observation products (CMAP and GPCP) are included in a (black solid lines). The multi-model mean (MMM) is represented by a black dashed line in all three panels. Box plots in c cover the 10th–90th percentile range of a change in rain rate

Figure 13 b, c plot the mid-century (2040–2060) projections in the annual cycle under the RCP8.5 scenario for each model and the multi-model mean together with the difference from the current climate. These figures indicate that the models are projecting a slight flattening of the annual cycle with the winter becoming wetter and the summer drier. For the spring season of interest here, the multi-model projections also indicate a drying but less pronounced than for the summer. From Fig. 14 it is evident that most of the 36 models project drying in spring but since 8 models project wetter conditions, then when averaged across the province, the multi-model mean indicates only very slight drying in this season. However, given the complex topography and meteorology, highly varying soil and vegetation conditions in this province (e.g. 6 of the 7 biomes found in South Africa also occur in the Eastern Cape) together with the presence of the highly variable and intense Agulhas Current to its south, it is not surprising that the models should show a spread in projections over the Eastern Cape and have difficulties in accurately representing its climate. A substantial part of the difficulties that such models have with representing the region’s climate likely results from their ability to adequately represent the characteristics of the cloud bands. As previously highlighted, changes in the frequency of cloud bands during SON can result in wetter (more cloud bands) or drier (fewer cloud bands) conditions in the Eastern Cape. In a comprehensive analysis of the ability of CMIP5 models to represent cloud bands over southern Africa, James et al. ( 2020 ) found that there are large variations in the modelled average locations and frequencies of these weather systems between the models even though all models correctly simulate the large scale generation and evolution of the cloud bands. Since the Eastern Cape is only part of the large area in southern Africa affected by cloud bands, small errors in the model simulations of cloud bands can therefore lead to substantial discrepancies in the resulting model simulation of seasonal rainfall. This large model spread in seasonal rainfall simulation means that future projections need to be viewed with caution and that the complex geography and meteorology of this region is likely to continue to pose significant challenges for climate models.

Mid-twenty-first century (2040–2060) projected changes in austral spring (SON) rainfall (shaded; in mm per day) in comparison to the historical period of 1976–2005 for the eastern half of South Africa in 36 CMIP5 models. The percentage change (%) given in the right-hand corner of each panel denotes the change averaged across the polygon (charcoal line) across the Eastern Cape river basins. The multi-model mean (MMM) in given in the last panel

4 Conclusions

The Eastern Cape province of South Africa lies in the transition zone between the winter rainfall (western South Africa) and the summer rainfall (rest of subtropical southern Africa) regions which makes it an interesting but complex region to study. It is characterised by strong topographic, soil moisture and vegetation gradients and its coast is close to the highly variable Agulhas Current (the most intense western boundary current in the global oceans). Given its latitudinal range of about 30–34° S, the Eastern Cape is influenced by both tropical and midlatitude weather systems and their interactions further adding to the complexity of its meteorology. Severe droughts and flooding events are frequently experienced in the Eastern Cape which cause substantial socio-economic impacts, including loss of life in some cases. Currently, the province is suffering an intense drought (which started in 2015) with several urban areas under stringent water restrictions and having been close to have run out of piped water from the corresponding dams.

Although the 2015-drought has manifest itself throughout all seasons, focus here has been placed on spring (September–November) which shows the strongest and most coherent signal. On average, this season contributes between 25 and 35% of the annual total rainfall. A composite analysis of the 5 driest (wettest) springs since 1981 which are chosen on the basis that the extended summer are also anomalously dry (wet) indicated that these were related to a large cyclonic (anticyclonic) mid-tropospheric anomaly located to the south and southeast of South Africa that seems in turn to be related to changes in the zonal wavenumber 3 pattern. Over southern Africa, the composites suggest that dry (wet) springs are associated with a weaker (stronger) near-surface Angola Low and stronger (weaker) mid-level Botswana High with enhanced (reduced) subsidence which lead to less (more) favourable conditions for cloud bands to develop. None of the large-scale climate modes that are known to affect subtropical southern Africa show statistically significant correlations with spring rainfall over the Eastern Cape but the Southern Annular Mode is significantly correlated (positive) with summer rainfall.

Trends in spring rainfall characteristics were also investigated. Most of the Eastern Cape shows a statistically significant decline in spring rainfall, particularly in the east and northeast of the province. This east/northeastern region is in fact part of a larger region of eastern South Africa (with strongest trends in this part of the Eastern Cape, Lesotho and eastern Free State) (not shown) which shows significant decreasing trends in spring rainfall totals and rain days. Elsewhere, part of the dam catchment areas for the largest city of Port Elizabeth also show significantly decreasing trends. Overall, the results suggest that the rainfall gradient across the province is weakening, at least in spring. Most of the decreasing rainfall trend seems to result from a reduction in the number of rainfall days but not in heavy rainfall days (defined as more than > 10 mm per day).

Analysis of mid-century (2040–2060) projections under the RCP8.5 scenario suggested that there may be a slight flattening of the annual cycle over the Eastern Cape with the winter becoming wetter and the summer drier. For the spring season of interest here, the multi-model projections also indicated drying but less pronounced than for the summer. Although most of the 36 models analysed project a spring drying over the Eastern Cape, the multi-model mean indicates only very slight drying in this season. However, given the strong land and ocean surface gradients in the region and its sensitivity to both tropical and midlatitude circulation, it is not surprising that the models should show a spread in projections over the Eastern Cape and have difficulties in accurately representing its climate. Furthermore, the difficulties relative to observations that CMIP5 models have in simulating the frequency and location of cloud bands (James et al. 2020 ), a key rainfall-producing system over the region, adds to the uncertainty in future rainfall changes. Caution therefore needs to be taken regarding future projections over this region. Nonetheless, the complex geography and meteorology of this region does provide an interesting test bed for climate models.

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Acknowledgements

The first author gratefully acknowledges the South African National Antarctic Programme of the NRF for partially funding her PhD research. The authors thank the South African Weather Service (SAWS) for providing rainfall data and Pierre Kloppers (CSAG, UCT) for assistance with data quality control. NCEP and OISST data were obtained from the NOAA/ESRL Physical Sciences Division, Boulder Colorado website at https://www.esrl.noaa.gov/psd/ . Daily CHIRPS data have been downloaded from the Climate Hazards Group data website ( https://www.chc.ucsb.edu/data/chirps ). The Nino 3.4 index, SAM index and SIOD were downloaded from the KNMI Climate Explorer ( https://climexp.knmi.nl ). We also acknowledge the World Climate Research Programme’s Working Group on Coupled Modelling responsible for CMIP5 model data, which was provided by the Program for Climate Model Diagnosis and Intercomparison (PCMDI; https://pcmdi.llnl.gov/ ).

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Mahlalela, P.T., Blamey, R.C., Hart, N.C.G. et al. Drought in the Eastern Cape region of South Africa and trends in rainfall characteristics. Clim Dyn 55 , 2743–2759 (2020). https://doi.org/10.1007/s00382-020-05413-0

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Received : 25 March 2020

Accepted : 07 August 2020

Published : 14 August 2020

Issue Date : November 2020

DOI : https://doi.org/10.1007/s00382-020-05413-0

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Questions and Answers about Droughts Active

This page offers some questions and answers about the hydrology of droughts. This information is taken from the web site of the U.S. Geological Survey Water Science Center in Maryland, Delaware, and Washington, D.C. Some content was modified and adapted to Puerto Rico.Droughts: Droughts: https://www.usgs.gov/special-topic/water-science-school/science/droughts-things-know?qt-science_center_objects=0#qt-science_center_objects

What is a drought?

What causes drought?

When does a drought begin?

Does a shortage of rain mean that a drought will occur?

Why doesn't a drought go away when it rains?

Can drought affect the water level in wells?

While it is relatively easy to define what a hurricane or earthquake is, defining a drought is more subjective. Droughts do not have the immediate effects of floods, but sustained droughts can cause economic stress throughout an area. The word "drought" has various meanings, depending on a person's perspective. To a farmer, a drought is a period of moisture deficiency that affects the crops under cultivation—even two weeks without rainfall can stress many crops during certain periods of the growing cycle. To a meteorologist, a drought is a prolonged period when precipitation is less than normal. To a water manager, a drought is a deficiency in water supply that affects water availability and water quality. To a hydrologist, a drought is an extended period of decreased precipitation and streamflow. Droughts in Puerto Rico have severely affected municipal and industrial water supplies, agriculture, stream water quality, recreation at major reservoirs, hydropower generation, and forest resources.

What causes droughts?

A drought is a period of drier-than-normal conditions that results in water-related problems. Precipitation falls in uneven patterns across the country. The amount of precipitation at a particular location varies from year to year, but over a period of years, the average amount is fairly constant. The spatial distribution of rainfall in Puerto Rico is variable. Rainfall is greatest in the Sierra de Luquillo rainforest in the eastern part of Puerto Rico. The mean annual total rainfall in Sierra de Luquillo is 169 inches per year (in/yr). The least amount of rainfall occurs in the vicinity of Guánica at Ensenada in southwestern Puerto Rico. In this area, the mean annual total rainfall is 30 in/yr.

Air temperatures fluctuate little throughout the year as a result of relatively constant insolation (that is, solar radiation) and seawater temperatures. The rate of delivery of solar radiation is nearly constant because the difference in daylight hours varies little throughout the year. Between the longest day of the year (13 hours, 13 minutes) and the shortest day (11 hours, 2 minutes), the amount of daylight differs by only slightly more than 2 hours. Mean monthly seawater temperatures vary by only about 4 °C; the mean maximum water temperature of 28 °C occurs in October, and the mean minimum water temperature of 24 °C occurs in January.

Major rainfall events producing substantial volumes of rain in Puerto Rico and the outlying islands are caused by one of two climate mechanisms—the passage of an easterly wave or the passage of a cold front. Easterly waves generally occur during May to November with some having sufficient intensity to evolve into tropical storms and (or) hurricanes. Cold fronts generally occur during November to April and may produce sufficient rainfall to cause flooding even during the period from December to March, which is a relatively dry period. The number of easterly waves or cold fronts passing over the region in any given year ultimately determines whether the region experiences relatively dry conditions or wet conditions. As a result, localized droughts occur yearly within many of the geographic areas of Puerto Rico.

Reference: Hydrogeology of Puerto Rico and the Outlying Islands of Vieques, Culebra, and Mona.

The beginning of a drought is difficult to determine. Several weeks, months, or even years may pass before people know that a drought is occurring. The end of a drought can occur as gradually as it began. Dry periods can last for 10 years or more. During the 1930's, most of the United States was much drier than normal. In Puerto Rico, for the 50-year period (1961 to 2010) there were six (6) years considered as drought years (1964, 1967, 1973, 1991, 1994, and 1997).

Climatological drought conditions in the Eastern Interior Climatic area of Puerto Rico typically occur when the annual rainfall amount is less than 70-80 percent of normal rainfall (a deficit of 20 to 30 percent below normal).

A period of below-normal rainfall does not necessarily result in drought conditions. Some rain returns to the air as water vapor when water evaporates from water surfaces and from moist soil. Plant roots draw some of the moisture from the soil and return it to the air through a process called transpiration. The total amount of water returned to the air by these processes is called evapotranspiration. Sunlight, humidity, temperature, and wind affect the rate of evapotranspiration. When evapotranspiration rates are high, soils can lose moisture and dry conditions can develop. During cool, cloudy weather, evapotranspiration rates may be low enough to offset periods of below-normal precipitation and a drought may be less severe or may not develop at all.

Reference: Moreland, 1993.

Rainfall in any form will provide some drought relief. A good analogy might be how medicine and illness relate to each other. A single dose of medicine can alleviate symptoms of illness, but it usually takes a sustained program of medication to cure an illness. Likewise, a single rainstorm will not break the drought, but it may provide temporary relief.

A light to moderate shower will probably only provide cosmetic relief. It might make folks feel better for awhile, provide cooling, and make the vegetation perk up. During the growing season, most of the rain that falls will be quickly evaporated or used by plants. Its impact is short term.

A thunderstorm will provide some of the same benefits as the shower, but it also may cause loss of life and property if it is severe. Thunderstorms often produce large amounts of precipitation in a very short time, and most of the rain will run off into drainage channels and streams rather than soak into the ground. If the rain happens to fall upstream of a reservoir, much of the runoff will be captured by the reservoir and add to the available water supply. No matter where the rain falls, stream levels will rise quickly and flooding may result. Also, because the rainfall and runoff can be intense, the resulting runoff can carry significant loads of sediment and pollutants that are washed from the land surface.

Soaking rains are the best medicine to alleviate drought. Water that enters the soil recharges ground water, which in turn sustains vegetation and feeds streams during periods when it is not raining. A single soaking rain will provide lasting relief from drought conditions, but multiple such rains over several months may be required to break a drought and return conditions to within the normal range.

Tropical storm rains are usually of the soaking variety, although they may also be intense such as during a thunderstorm and lead to some of the same problems. Tropical storms often produce more total rainfall than a "regular" soaking rain and can provide longer relief than a single soaking rain. However, tropical rains may also be of such intensity that they exceed the capacity of soil to absorb water and often result in significant runoff and flooding. Tropical rains can help to fill water-supply reservoirs and provide long-term drought insurance. If significant rainfall does not occur upstream of reservoirs, the drought relief aspects of tropical storms may be of only little consequence. All things considered, a single tropical storm at the right place, at the right time, and with the right amount of rainfall can break a drought.

Considering all of the above, even when a drought has been broken it may not be truly over. The benefits of substantial rainfall such as from a tropical storm may last for months, but a return to normal rainfall patterns and amounts is necessary for conditions in streams, reservoirs, and ground water to also return to normal.

Ground water, which is found in aquifers below the surface of the Earth, is one of the Nation's most important natural resources. Ground water is used to provide a large portion of the Nation's population with drinking water, it provides business and industries water for their purposes, and is used extensively for irrigation.

The water level in the aquifer that supplies a well does not always stay the same. Droughts, seasonal variations in rainfall, and pumping affect the height of the underground water levels. If a well is pumped at a faster rate than the aquifer around it is recharged by precipitation or other underground flow, then water levels in the well can be lowered. This can happen during drought, due to the extreme deficit of rain. The water level in a well can also be lowered if other wells near it are withdrawing too much water.

Gómez-Gómez and others, 2014, Drought : Hydrogeology of Puerto Rico and the Outlying Islands of Vieques, Culebra, and Mona , Scientific Investigations Map 3296., http://dx.doi.org/10.3133/sim329 6

Moreland, J.A., 1993, Drought : U.S. Geological Survey Water Fact Sheet, Open-File Report 93-642, 2p.

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Droughts: Notes for UPSC Geograpahy

Drought is a phenomenon that comes under geography in the strict sense of the word but has reverberations across various fields. This is because droughts affect the livelihood and economies and even lives of people affected by it. Hence, it assumes importance for the UPSC exam. In this article, we talk about droughts for the IAS exam .

Definition of Drought

The term ‘Drought’ in simple words is the absence of water for a long period of time, at a place where it is considered abnormal as compared to its usual conditions. The distribution of water on the earth’s surface is not even. Some places have lots of freshwater e.g. rivers, lakes, lagoons, ponds etc. and they are continuously replenished by rainfall and water from underground.

If a region that has had lots of rainfall , goes for a couple of weeks without rains, and people, animals and plants begin to experience a bit of dryness, it can be called a drought. Drought can be defined as a relatively long time where there is not enough water than there usually is, as a result of dry weather, to support human, animal and plant life. Droughts become an issue only when it begins to affect water supply for irrigation, municipal, industrial, energy, and ecosystem function. Severe droughts can have serious consequences.

Recently, the government of England has formally declared parts of England. It was declared after a period of prolonged hot and dry weather.

The declaration of drought serves as a recognition of the water scarcity situation and the need for proactive measures to manage water resources effectively.

Implications of the declaration: The declaration abrings various actions and regulations to address the water scarcity issue and ensure the sustainable use of available water resources.

Water Companies’ Drought Plans and Restrictions: Water companies are required to have a drought plan in place, outlining the restrictions they may implement on their customers during a drought. These plans serve as guidelines for managing water supplies efficiently and responsibly.
Drought Orders and Permits for Water Management: During a drought, water companies have the option to apply for drought orders and permits. This helps ensure a more sustainable water supply during times of scarcity.
Restrictions on Non-Essential Water Use: To conserve water during a drought, restrictions can be imposed on non-essential water use. This includes measures such as limiting water usage in commercial car washes and swimming pools.
Restrictions for Farmers: Farmers may face restrictions on water usage for spray irrigation. These measures are intended to balance the water needs of agricultural activities with the overall water availability in drought-affected areas.
Government Intervention in Industrial and Food Processing Water Use: The government can impose restrictions on water use in industrial manufacturing or food processing sectors.
Conservation Measures in Dry Conditions: In drought conditions, Natural England, the government’s conservation advisory body, may restrict access to certain areas, such as national nature reserves, if there is a risk of fire caused by dry conditions. These measures aim to protect valuable natural habitats and prevent wildfires, which can be exacerbated during periods of prolonged hot and dry weather.

Types of Drought

There are three types of droughts known to the scientific community:

Meteorological drought occurs when there is a prolonged time with less than average precipitation. Such type of droughts can be triggered by a high level of reflected sunlight and above-average prevalence of high-pressure systems, winds carrying continental, rather than oceanic air masses.
Agricultural droughts affect crop production or the ecology of the range. This condition can also arise independently from any change in precipitation levels when either increased irrigation or soil conditions and erosion triggered by poorly planned agricultural activities cause a shortfall in water available to the crops.
Hydrological drought is brought about when the water reserves available in sources such as aquifers, lakes and reservoirs fall below a locally significant threshold. Hydrological drought tends to show up more slowly because it involves stored water that is used but not replenished. Like an agricultural drought, this can be triggered by more than just a loss of rainfall.
Socio-Economic Drought refers to the abnormal water shortage that affects socio economic condition of a region.

For more notes on UPSC Geography , visit the linked article

Drought-prone districts in India comprise nearly 1/6th of this country in terms of area. These areas receive an annual rainfall of around 60 cm or less.
These situations can be attributed to human malpractices such asI recent year drought conditions have become recurring due to reasons as climate change, overuse of water resource, pollution, urbanization, etc.
Drought is declared by the respective State Governments taking into account rainfall situation, crop growth, etc.

Consequences of Drought

The effects of droughts can be divided into three groups: environmental, economic and social.

Environmental effects: Lower surface and subterranean water-levels, lower flow-levels (with a decrease below the minimum leading to direct danger for amphibian life), increased pollution of surface water, the drying out of wetlands, more and larger fires, higher deflation intensity, loss of biodiversity , worse health of trees and the appearance of pests and dendroid diseases.
Economic losses: Economic consequences include lower agricultural, forests, game and fishing output, higher food-production costs, lower energy-production levels in hydro plants, losses caused by depleted water tourism and transport revenue, problems with water supply for the energy sector and for technological processes in metallurgy, mining industries and disruption of water supplies for municipal economies.
Social costs include the negative effect on the health of people directly exposed to this phenomenon (excessive heat waves), a possible limitation of water supplies, increased pollution levels, high food-costs, stress caused by failed harvests, etc. This explains why droughts and freshwater shortages operate as a factor which increases the gap between developed and developing countries.

Effects vary according to vulnerability. For example, subsistence farmers are more likely to migrate during drought because they do not have alternative food sources. Areas with populations that depend on water sources as a major food-source are more vulnerable to famine.

Frequently Asked Questions Related to Drought

What are the four types of drought.

As a result, the climatological community has defined four types of drought:

1) Meteorological drought 2) Hydrological drought 3) Agricultural drought 4) Socioeconomic drought.

Is a drought a natural disaster?

Droughts – UPSC Notes:- Download PDF Here

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The Impact of Drought in South Africa Research Grade 11 Geography

The Impact of Drought in South Africa Research Geography Grade 11: South Africa has experienced a series of droughts over the past few decades, with significant impacts on the environment, economy, and society. As Grade 11 learners, it is crucial to understand the causes and consequences of drought in order to develop solutions for a more sustainable future. This article aims to provide a comprehensive research guide for Grade 11 students on the impact of drought in South Africa.

Table of Contents

The Impact of Drought in South Africa Research Grade 11

Understanding Drought

Before diving into the impacts of drought, it is essential to understand what drought is and how it is classified. Drought is a prolonged period of abnormally low rainfall, leading to a shortage of water. Droughts can be classified into three main types:

Meteorological drought: Occurs when there is a significant decrease in precipitation compared to the average for a specific region and time period.
Agricultural drought: Occurs when there is insufficient soil moisture to meet the needs of crops, leading to decreased agricultural productivity.
Hydrological drought: Occurs when there is a deficiency in surface and subsurface water resources, such as rivers, lakes, and groundwater.
Causes of Drought in South Africa

Several factors contribute to the occurrence of drought in South Africa:

Climate change: As global temperatures rise, the frequency and intensity of droughts are likely to increase. Changes in precipitation patterns can exacerbate water scarcity in regions already prone to drought.
El Niño Southern Oscillation (ENSO): This climate phenomenon can lead to drought conditions in South Africa when the warm phase, known as El Niño, occurs. This results in suppressed rainfall over the southern African region.
Land use practices: Unsustainable land management, such as deforestation, can reduce the ability of ecosystems to store water and contribute to drought.
Environmental Impacts

Drought in South Africa has a range of environmental impacts:

Decreased water availability: Reduced water levels in rivers, lakes, and dams can lead to water restrictions and increased competition for water resources.
Loss of biodiversity: Drought can lead to the death of plants and animals, affecting ecosystems and reducing biodiversity.
Soil degradation: Drought can cause soil to become compacted, eroded, or lose its fertility, reducing its ability to support plant life.
Economic Impacts

The economic impacts of drought in South Africa are far-reaching:

Agricultural losses: Reduced crop yields and livestock productivity can lead to food shortages and increased food prices, affecting both farmers and consumers.
Unemployment: The agricultural sector is a significant employer in South Africa. Drought can result in job losses for farmworkers and related industries.
Reduced tourism: South Africa’s natural beauty is a significant tourist draw. However, drought can negatively impact water-based recreational activities and wildlife populations, deterring tourists and affecting the tourism industry.
Social Impacts

Drought can have severe social consequences in South Africa:

Water scarcity: Limited access to clean water can lead to waterborne diseases and affect sanitation, negatively impacting public health.
Food insecurity: Food shortages and increased prices can exacerbate food insecurity, particularly for vulnerable populations.
Mental health: The stress of dealing with the consequences of drought can lead to increased anxiety, depression, and other mental health issues among affected individuals and communities.
Mitigation and Adaptation Strategies

To minimize the impact of drought and increase resilience, South Africa needs to implement various mitigation and adaptation strategies:

Water resource management: Improved water resource management, including the development of new water infrastructure and more efficient water use, is crucial for ensuring water security.
Sustainable agriculture: Adopting drought-resistant crops and sustainable farming practices can help reduce the impact of drought on agricultural productivity.
Reforestation and land management: Reforestation and better land management practices can improve water retention and reduce soil erosion, helping to alleviate drought conditions.
Education and awareness: Encouraging communities to adopt water-saving practices and promoting awareness of the consequences of drought is essential for fostering a culture of water conservation.
Climate change mitigation: Reducing greenhouse gas emissions and supporting global efforts to address climate change can help limit the frequency and intensity of droughts in the future.

Drought is a significant issue in South Africa, with wide-ranging environmental, economic, and social impacts. For Grade 11 students researching the impact of drought, understanding the causes, consequences, and potential solutions is essential. By implementing effective mitigation and adaptation strategies, South Africa can better manage the effects of drought and create a more sustainable and resilient future.

Geography Grade 11 Research Memorandum (Answers & Assistance)

Below are the relevant resources for The Impact of Drought in South Africa Research, Geography Grade 11

A map of South Africa, that indicates the drought-stricken areas
Annual rainfall graphs of the past five years
Pictures of the different types of droughts
A brief discussion on the annual rainfall graphs
How can droughts be triggered by Physical (natural) conditions
How can droughts be triggered by Human activities
Outline the negative impact of droughts on the economy of South Africa
Outline the negative impact of droughts on the farmers of South Africa
Discuss drought prevention and drought preparation strategies
What is the relationship between climate change and the regularity of droughts
What is the way forward regarding droughts for the government and the people of South Africa

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Geography Grade 11 Research about Drought Memorandum

May 08, 2023

The Geography Grade 11 Research about Drought Memorandum is a task on the drought that aims to equip learners with skills in research, analysis, interpretation, and communication. Learners will be expected to demonstrate their understanding of drought, its causes, impacts, and management strategies. This research task will require students to gather data from various sources, analyze the information, and present it in a clear and concise manner. This paper will explore the possible subtopics and questions that learners can explore, the importance of the research memorandum, and how learners can prepare for their exams.

Causes of Drought

The first subtopic that learners can explore is the causes of drought. This section aims to provide an understanding of what drought is and the different types of drought . The research task should explain the physical and human causes of drought. Physical causes may include climate variability, while human causes may include deforestation, over-extraction of groundwater, and poor water management practices. Climate change is also a crucial factor that impacts drought, and learners can investigate how climate change exacerbates drought conditions.

Impacts of Drought

The second subtopic that learners can explore is the impacts of drought . This section should provide an understanding of the social, economic, and environmental impacts of drought. Learners can investigate how different regions and communities experience drought differently, as well as the short-term and long-term effects of drought. The research task should describe the loss of vegetation, soil erosion, and the depletion of water resources. Learners can also investigate how drought affects wildlife and biodiversity.

Management Strategies for Drought

The third subtopic that learners can explore is management strategies for drought. This section should provide an understanding of the different drought management strategies used in different regions. Learners can investigate the effectiveness of these strategies and the challenges and limitations of drought management. They can also explore the strategies used to mitigate the impacts of drought, including water conservation, drought-resistant crops, and alternative water sources. The research task can also discuss how communities can adapt to drought and manage water resources more sustainably.

The Importance of the Research Memorandum

The Geography Grade 11 Research about Drought Memorandum is an essential resource for learners preparing for the Geography Grade 11 research task on drought. It provides a clear guideline on what is expected from the learners and how to approach the research task. Learners can gain insight into the research question, methodology, and requirements for the final report. The memorandum can also provide a clear understanding of the scope of the research task and the subtopics that learners should explore.

Geography Grade 11 Research about Drought Memorandum to Prepare Your Exams

To prepare for exams on geography research tasks, learners should understand the research process. They should be familiar with the steps involved in data collection, analysis, and interpretation. Learners should also develop critical thinking skills and be able to analyze and evaluate information critically. They should be able to draw logical conclusions from the data and communicate their findings effectively, both in writing and verbally.

Familiarizing themselves with the curriculum is also essential. Learners should have a good understanding of the key concepts, theories, and principles covered in the Geography Grade 11 curriculum. Seeking assistance when needed is also crucial. Learners should not hesitate to seek help from their teacher or peers if they are struggling with any aspect of the research task or exam preparation.

The Geography Grade 11 research task about drought memorandum is a significant undertaking that requires learners to acquire skills in research, analysis, interpretation, and communication. The research task covers the causes of drought, the impacts of drought, and management strategies for drought. Learners should use both primary and secondary sources, such as scientific articles, government reports, and interviews with experts in the field, to support their findings. The research memorandum is an essential resource for learners preparing for the research task, providing clear guidelines on what is expected from them. To prepare for exams, learners should understand the research process, develop critical thinking skills, practice effective communication, familiarize themselves with the curriculum, and seek assistance when needed. In addition to these general strategies, learners preparing for exams on geography research tasks should also focus on understanding the specific content related to drought, including its causes, impacts, and management strategies. They should gather information from a variety of sources, such as academic journals, government reports , and case studies, and analyze and interpret the data to draw conclusions and make recommendations. It is also important for learners to practice writing clear and concise reports that effectively communicate their findings and ideas. This can involve organizing their ideas in a logical manner, using appropriate headings and subheadings, and providing relevant examples and evidence to support their arguments. Finally, learners should practice time management skills to ensure they have enough time to complete the research task and review their work before submitting it.

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Drought Pushes Millions Into ‘Acute Hunger’ in Southern Africa

The disaster, intensified by El Niño, is devastating communities across several countries, killing crops and livestock and sending food prices soaring.

A man wearing a tan jacket and red shoes stands in a dusty field amid rows of dead corn, holding a dried stalk in two hands.

By Somini Sengupta and Manuela Andreoni

An estimated 20 million people in southern Africa are facing what the United Nations calls “acute hunger” as one of the worst droughts in more than four decades shrivels crops, decimates livestock and, after years of rising food prices brought on by pandemic and war, spikes the price of corn, the region’s staple crop.

Malawi, Zambia and Zimbabwe have all declared national emergencies.

It is a bitter foretaste of what a warming climate is projected to bring to a region that’s likely to be acutely affected by climate change, though scientists said on Thursday that the current drought is more driven by the natural weather cycle known as El Niño than by global warming.

Its effects are all the more punishing because in the past few years the region had been hit by cyclones, unusually heavy rains and a widening outbreak of cholera.

‘Urgent help’ is needed

The rains this year began late and were lower than average. In February, when crops need it most, parts of Zimbabwe, Zambia, Malawi, Angola, Mozambique and Botswana received a fifth of the typical rainfall.

That’s devastating for these largely agrarian countries, where farmers rely entirely on the rains.

In southern Malawi, in a district called Chikwawa, some residents were wading into a river rife with crocodiles to collect a wild tuber known as nyika to curb their hunger. “My area needs urgent help,” the local leader, who identified himself as Chief Chimombo, said.

Elsewhere, cattle in search of water walked into fields still muddy from last year’s heavy rains, only to get stuck, said Chikondi Chabvuta, a Malawi-based aid worker with CARE, the international relief organization. Thousands of cattle deaths have been reported in the region, according to the group.

The first few months of every year, just before the harvest begins in late April and May, are usually a lean season. This year, because harvests are projected to be significantly lower , the lean season is likely to last longer. “The food security situation is very bad and is expected to get worse,” Ms. Chabvuta said.

Local corn prices have risen sharply. In Zambia, the price more than doubled between January 2022 and January of this year, according to the United Nations Food and Agriculture Organization . In Malawi, it rose fourfold.

The F.A.O. pointed out that, in addition to low yields, grain prices have been abnormally high because of the war in Ukraine, one of the world’s biggest grain exporters, as well as weak currencies in several southern African countries, making it expensive to buy imported food, fuel and fertilizers.

Why it’s happening

According to an analysis published Thursday by World Weather Attribution, an international coalition of scientists that focuses on rapid assessment of extreme weather events, the driving force behind the current drought is El Niño, a natural weather phenomenon that heats parts of the Pacific Ocean every few years and tweaks the weather in different ways in different parts of the world. In Southern Africa, El Niños tend to bring below-average rainfall.

El Niño made this drought twice as likely, the study concluded. That weather pattern is now weakening, but a repeat is expected soon.

The drought may also have been worsened by deforestation, which throws off local rainfall patterns and degrades soils, the study concluded.

Droughts are notoriously hard to attribute to global warming. That is particularly true in regions like Southern Africa, in part because it doesn’t have a dense network of weather stations offering detailed historical data.

Scientists are uncertain as to whether climate change played a role in this particular drought. However, there is little uncertainty about the long-term effects of climate change in this part of the world.

The average temperature in Southern Africa has risen by 1.04 to 1.8 degrees Celsius in the past 50 years , according to the Intergovernmental Panel on Climate Change, and the number of hot days has increased. That makes a dry year worse. Plants and animals are thirstier. Moisture evaporates. Soils dry out. Scientific models indicate that Southern Africa is becoming drier overall .

The Intergovernmental Panel on Climate Change calls Southern Africa a climate change “hot spot in terms of both hot extremes and drying.”

The costs of adaptation

To the millions of people trying to cope with this drought, it hardly matters whether climate change or something else is responsible for why the skies have gone dry.

What matters is whether these communities can adapt fast enough to weather shocks.

“It’s really important that resilience to droughts, especially in these parts of the continent, should really be improved,” said Joyce Kimutai, one of the authors of the study and a researcher at the Grantham Institute, a climate and environment center at Imperial College London.

There are existing solutions that need money to put into effect: early warning systems that inform people about what to expect, insurance and other social safety programs to help them prepare, as well as diversifying what farmers plant. Corn is extremely vulnerable to heat and erratic rains.

Golden Matonga contributed reporting.

Somini Sengupta is the international climate reporter on the Times climate team. More about Somini Sengupta

Manuela Andreoni is a Times climate and environmental reporter and a writer for the Climate Forward newsletter. More about Manuela Andreoni

Learn More About Climate Change

Have questions about climate change? Our F.A.Q. will tackle your climate questions, big and small .

“Buying Time,” a new series from The New York Times, looks at the risky ways humans are starting to manipulate nature to fight climate change.

Big brands like Procter & Gamble and Nestlé say a new generation of recycling plants will help them meet environmental goals, but the technology is struggling to deliver .

The Italian energy giant Eni sees future profits from collecting carbon dioxide and pumping it into natural gas fields that have been exhausted.

New satellite-based research reveals how land along the East Coast is slumping into the ocean, compounding the danger from global sea level rise . A major culprit: the overpumping of groundwater.

Did you know the ♻ symbol doesn’t mean something is actually recyclable ? Read on about how we got here, and what can be done.

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COMMENTS

Drought
A drought is a period of time when an area or region experiences below-normal precipitation.The lack of adequate precipitation, either rain or snow, can cause reduced soil moisture or groundwater, diminished stream flow, crop damage, and a general water shortage.. Droughts are the second-most costly weather events after hurricanes.Unlike with sudden weather events such as hurricanes, tornadoes ...
Essay on Drought for Students and Children
500+ Words Essay on Drought. Drought is a dangerous condition which decreases the quality of life. It is termed as a natural disaster with harmful effects. A drought usually occurs when a region faces a shortage of water. This is mainly due to lesser rainfalls. In addition, droughts have proven to be fatal for mankind and wildlife as well.
What are the causes of drought?
A lack of water in stores such as rivers, lakes, reservoirs and aquifers (water stored underground naturally) can lead to drought. Areas that rely on rainfall and surface water are more likely to experience drought. Surface water quickly evaporates in warm, dry conditions leading to an increased risk of drought.
Droughts and Climate Change
Drought is a serious environmental threat across the United States. Climate change exacerbates droughts by making them more frequent, longer, and more severe. The USGS works with state and federal partners to study, monitor, and help mitigate drought impacts across the U.S. now and into the future.
Drought
Drought is a natural disaster that has plagued human society throughout history. However, the meaning of drought varies by perspective and academic discipline, and the cause of drought is difficult to pinpoint. Despite the variation in its meaning, drought generally refers to the condition of an abnormally low amount of water for a given climate.
Essay on Drought: Top 9 Essays
Essay # 8. Drought Prone Areas: Out of the total geographical area of India, almost one-sixth area with 12 per cent of the population is drought prone; the areas that receive an annual rainfall up to 600 mm are the most prone. Irrigation Commission (1972) had identified 67 districts as drought prone.
Drought
The beginning of a drought is difficult to determine. Several weeks, months, or even years might pass before people know that a drought is occurring. The end of a drought can occur as gradually as it began. The first evidence of drought is usually seen in records of rainfall. Within a short period of time, the amount of moisture in soils can ...
Climate change has contributed to droughts since 1900, and is likely to
Climate change has contributed to droughts since 1900—and may get worse. A first-of-its-kind study confirms the connection between climate change and droughts and deluges over the past century.
PDF FACTSHEET: Drought and its socio-economic impacts
FACTSHEET: Drought and its socio-economic impacts Facts about drought1 1. Droughts are a global phenomenon and affect countries in every region of the world. 2. Globally, the area affected by drought is increasing every year. 3. Over the Mediterranean region, drying may be increasing. 4. Globally, droughts are also becoming more severe and ...
Drought Essay in English for Students
Get the huge list of more than 500 Essay Topics and Ideas. Conclusion of Drought Essay. To sum it up, drought is a difficult situation with which we have to deal with. When the severity is high, it becomes all the more difficult to manage it. A lot of people get affected because of droughts every year as it reduces human activities.
Drought in the Eastern Cape region of South Africa and ...
The Eastern Cape is of interest not just because of the severe drought that it is currently experiencing but also because its western parts lie near the transition zone between the summer (most of southern Africa) and winter rainfall regions (southwestern South Africa, Reason et al. 2002; Blamey et al. 2018b) and because it is a region of sharp vegetation, soil moisture and topographic ...
Questions and Answers about Droughts
Droughts, seasonal variations in rainfall, and pumping affect the height of the underground water levels. If a well is pumped at a faster rate than the aquifer around it is recharged by precipitation or other underground flow, then water levels in the well can be lowered. This can happen during drought, due to the extreme deficit of rain.
Essays on Drought
Research Report on Drought in Australia. 2 pages / 1064 words. Abstract This Research report is based on the major problem facing by Australian people and mainly farmers and their communities. Many farmers and local communities have been facing severe and prolonged drought. Australia has always had variation in the climate.
Droughts
Includes rain, snow, hail, sleet, drizzle, fog and mist. and more chance of drought. High-pressure systems reduce evaporation and moisture in the atmosphere. High-pressure systems reduce ...
(PDF) Drought: A Common Environmental Disaster
1. Introduction. Drought has been identiﬁed as an environmental hazard by scientists and agricultural. professionals. It has been described as a long period of a decrease in precipitation, such ...
Research Progress and Conceptual Insights on Drought Impacts and ...
Drought is a natural phenomenon which can cause widespread socio-economic and environmental impacts. Recent predictions suggest that drought frequency and intensity will increase in Southern Africa; therefore, there is a need for more scientific information on drought impacts and responses by vulnerable groups such as smallholder farmers. This scoping review examines the current state of ...
The Impact of Drought in South Africa: Research Grade 11
Conclusion. South Africa is a country that is susceptible to drought due to its semi-arid climate, which makes it vulnerable to the effects of climate variability and change. Drought has significant impacts on the country's social, economic, and environmental systems. This research task aims to equip Grade 11 learners with skills in research ...
Droughts: Definition, Types and Consequences for UPSC Geography
The term 'Drought' in simple words is the absence of water for a long period of time, at a place where it is considered abnormal as compared to its usual conditions. The distribution of water on the earth's surface is not even. Some places have lots of freshwater e.g. rivers, lakes, lagoons, ponds etc. and they are continuously ...
The Impact of Drought in South Africa Research Grade 11 Geography
Loss of biodiversity: Drought can lead to the death of plants and animals, affecting ecosystems and reducing biodiversity. Soil degradation: Drought can cause soil to become compacted, eroded, or lose its fertility, reducing its ability to support plant life. Economic Impacts. The economic impacts of drought in South Africa are far-reaching:
2.3.1 Causes of Drought
Causes of Drought. There are different causes of a drought. Meteorological. This is where an area receives less than usual amounts of rainfall. High-pressure systems block low-pressure rain-bearing systems. This reduces or prevents rain from falling. Hydrological. This is the impact of reduced rainfall on the water (hydrological) cycle, such as.
Geography Grade 11 Research about Drought Memorandum
The Geography Grade 11 Research about Drought Memorandum is a task on the drought that aims to equip learners with skills in research, analysis, interpretation, and communication. Learners will be expected to demonstrate their understanding of drought, its causes, impacts, and management strategies. This research task will require students to ...
Drought Pushes Millions Into 'Acute Hunger' in Southern Africa
An estimated 20 million people in southern Africa are facing what the United Nations calls "acute hunger" as one of the worst droughts in more than four decades shrivels crops, decimates ...