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A megadrought is an extreme and prolonged drought that lasts for 20 years or longer. Human activities, such as burning fossil fuels and deforestation, trap more energy from the sun in the atmosphere and are playing a critical role in exacerbating the drought, consequently drying the Southwest areas of the US.

What causes a megadrought?

Radiative forcing is one of the causes of a megadrought, which occurs when the Earth’s atmosphere captures more energy from the sun. The more energy retained in the atmosphere, the higher the rate of water evaporation. 

Physical Risk

Droughts are one of the most expensive natural disasters, and it is estimated that the average annual loss in the US in 2018 was between USD$10 billion and $14 billion. There are few studies that have estimated the monetary losses to the agricultural sector caused by drought. Among these studies, one suggested that the megadrought in the US from 1988 to 1989 had caused the loss of crops worth $15 billion. Analysts at the University of California evaluated the economic impact of the California drought on the US’s agricultural sector from 2014 to 2016 (the most recent megadrought). They disclosed significant losses in crops, dairy products and livestock, as well as additional groundwater pumping costs, with a combined loss of approximately $3.85 billion. At the same time, some researchers have disclosed that the reduction in crop yields has led to higher crop prices to try and offset the loss from this drought on agricultural revenue.

Efforts to Mitigate Physical Risk

International Water Management Institute (IWMI)’s efforts to support nations and regions preparing for climate shocks (such as a megadrought) involve enhancing farmers’ resilience. In recent years, the Institute developed an index-based flood insurance (IBFI) product to compensate farmers whose crops have been ruined as a result of floods.

The technology uses satellite data and modelling tools to estimate when the depth and duration of flooding exceeds predefined limits, triggering automatic payouts. Between 2017 and 2019, the IBFI scheme supported insurance payouts in India ($22 000) and Bangladesh ($31 500) to 1 306 out of 2 300 eligible farming households, increasing their resilience to floods and minimising their vulnerability to natural hazards.  A new trial seeks to build on the success of IBFI by bundling SMS-based weather information, advice on crop and water management methods, and fertilisers together with the insurance product. The trial covered 1 000 households, of which 450 benefited from an insurance payout of $12 500 each.

How Unilever is Mitigating its Water Risks 

Unilever is one of the largest fast-moving consumer brand companies in the world with over 400 different brands in almost 200 countries. Unilever is currently focused on creating ‘sustainable products’ for their consumers, and their vision is ‘to make sustainable living commonplace’. They created the Unilever Sustainable Living Plan to realise this vision. Unilever identified key issues and topics on a materiality matrix, and prioritised them based on current stakeholder importance and short-term business impact.

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Unilever’s materiality matrix, ranking their priorities based on current stakeholder importance and short-term business impact (Source: Unilever Materiality Matrix 2019/2020.

Unilever set three general goals: Improving health and well-being for more than 1 billion, Reducing environmental impact by half and enhancing livelihoods for millions. To improve its water usage, Unilever has pledged to halve the water associated with the consumer use of its products by 2020 and maintain the water abstraction levels for production at or below 2008 levels by 2020. In 2019, they exceeded their second goal, where the water abstraction levels are 47% lower compared to 2008. However, they failed to meet the first goal to halve consumer water consumption- water consumption is actually 1% greater in 2019 than in 2010.                       

Unilever’s manufacturing department does an exemplary job of meeting these goals. However, their products department greatly lags behind to meet these goals. Even though the manufacturing department does not pledge to halve manufacturing emissions, water consumption or waste, it does so for all three areas. The explicit goals for the products department to halve product emissions, water consumption and waste are more difficult to achieve. However, the product department fails to even maintain the level of emissions and water impact at 2010 levels. Unilever needs to address these product department weaknesses to better align with their vision to make sustainable living commonplace.

What Governments Are Doing to Mitigate Water Risk

In 2017, the US government developed a Global Water Strategy to aid the global water crisis. The strategy contains four main strategic objectives revolving around conserving and providing clean water sources to countries with high water risk.

The first objective is to promote sustainable access to safe drinking water and sanitation services, and to adopt key hygiene behaviours. The US aims to increase the amount of sources for safe drinking water and sanitation, while decreasing the mortality rate related to unsafe drinking water and unhygienic living standards.

The second objective is to encourage the sound management and protection of freshwater resources. This strategy primarily addresses physical water risk, in particular, flooding and groundwater deficiency. The US aims to support access to water supplies and protect ecosystems that provide these water supplies. It also focuses on improving preparedness for water-related disasters such as floods and megadroughts. 

The third objective is to reduce conflict by promoting cooperation on shared waters. This strategy aims to resolve the issues of river basins and aquifers shared between multiple countries without formal agreements. This is done by increasing mediation activities between such countries through the creation of  designated institutions to address these issues.

The last objective is to strengthen water sector governance, financing and institutions. This is done by improving upon environmental policies, building partnerships with other international organisations to support the development of water resources and increasing the amount of private and public resources mitigating water issues.

The US government has set various approaches to fulfil these four strategies. Most notably, it plans to use its scientific and technical expertise to assist countries that require the most assistance for countering water risk. It also plans to mediate with governments and organisations to better understand the needs of the community while raising funds necessary for  supporting the development of water and sanitation infrastructures. 

The strategy lists 13 ‘High Priority Countries’ that have high levels of water risk and assistance needs. Such countries include Afghanistan, Haiti, Indonesia and Uganda. The US will focus their attention on these countries, and have deliberated country-specific plans to better help these countries.

However, there are potential difficulties and risks that should be addressed. This is especially apparent for the third objective, where the US aims to reduce conflict by promoting cooperation on shared waters. It is extremely difficult for countries to agree and share water resources, especially in high-risk countries. Even if the US government is able to bring the conflicting parties together to discuss, it is unlikely that a formal consensus can be made immediately. In fact, greater conflict may arise when the two parties discuss formal conditions for cooperation. 

Drought and Climate Change

China suffers from both too much as well as too little water due to climate change. Southern parts of China and coastal cities are often flooded from typhoons, storm surges or river/pluvial floods while certain areas experience extreme drought; for example, the middle and the lower reaches of the Yangtze River is characterised by alternating periods of drought followed by floods.

Over-extraction of groundwater and falling water tables are significant problems in China- there is an average annual groundwater depletion rate of more than 10 billion cubic metres and water resource usage is set to peak in 2030 when the population also peaks. Groundwater extraction can lead to land subsidence- 60 000 sq kms of the ground surface in the country has sunk, with more than 50 cities suffering from severe land subsidence. Further, Asia’s ten largest rivers, including the Yangtze, Yellow, Mekong and Ganges, are fed by seasonal melting, which is being affected by the climate crisis.

Existing drought models are very simplistic and therefore lead to wrong predictions. Moreover, rainfall data is not collected in most regions in Asia. It is therefore very difficult to make any drought analysis on a meaningful grid case. Intensel Limited, an Asia startup focusing on physical climate risk assessment and predictions, models drought using a combination of several factors including snowmelt and other climate variables. In addition, Intensel’s dynamic climate models and AI technology is able to generate missing historical data, for example, granular rainfall data. Organisations such as these are vital, as the climate crisis is making these predictions even more difficult with changing trends, increasing variation of weather. 

This post was written in collaboration with Entela Benz, Adjunct Associate Professor at HKUST and CEO of Intensel.

A study has found that China’s Mekong River dams held back large amounts of water during a damaging drought in downstream countries in 2019 despite China experiencing higher-than-average water levels upstream. 

US-based research company, Eyes on Earth, conducted a ‘Wetness Index’ observational study, which looked at the wet season period from May to October and found that the severe lack of water in the Lower Mekong during the wet season of 2019 was largely influenced by the restriction of water flowing from the upper Mekong during that time.

China disputed the findings, saying that there was low rainfall during last year’s monsoon season on its portion of the 4 350km river.

However, satellite imagery of surface wetness in China’s Yunnan province, through which the Upper Mekong flows, suggest the region in 2019 actually had slightly above-average combined rainfall and snowmelt during the May to October wet season. 

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Mekong River, China: the Conflict

Last year’s drought, which saw the Lower Mekong at its lowest levels in more than 50 years, devastated farmers and fisherman and saw the river recede to expose sandbanks along some stretches, with some parts drying up entirely when fishing should have been plentiful. At one gauge in Chiang Saen in northern Thailand, such low water levels had never been recorded before. 

Alan Basist, co-author of the report, and his colleague studied this gauge over a 28-year period and calculated that dams in China had held back more than 410 feet of river height. 

The river supports 60 million people as it flows past Laos, Myanmar, Thailand and through Cambodia and Vietnam. Beijing’s control of the upstream Mekong provides as much as 70% of the downstream water in the dry season. 

“If the Chinese are stating that they were not contributing to the drought, the data does not support that position,” stated Basist. “There was a huge volume of water that was being held back in China”, Basist added. 

Adding to the downstream woes were sudden releases of water from China, which often came unannounced and drowned crops that had been planted near the banks because of the drought. Local fisheries have complained that their catches have faced a very steep decline, while agriculture harvests are stagnant as a result of the persistent droughts and unpredictable floods.

Studies by the Mekong River Commission, an intergovernmental organisation that works with governments of Laos, Cambodia, Thailand and Vietnam to jointly manage the shared water resources and the sustainable development of the river, further predicts that the decrease of local agricultural production will result in these countries being over-dependent on China for food imports, ‘making them even more vulnerable to Chinese influence’. 

In February, the Chinese foreign minister had asserted to regional foreign ministers that China was suffering from the drought as well. He added that even in the unprecedented times of the coronavirus outbreak, the government was being magnanimous in sending water downstream’. Basist, however, refutes this claim.

“You look at our mapping, and it’s bright blue with plenty of water in China and bright red from an extreme lack of water in Thailand and Cambodia,” he said. “China can regulate this river flow through dams and that appears to be exactly what it’s doing”. 

He adds, “The satellite data doesn’t lie, and there was plenty of water in the Tibetan Plateau, even as countries like Cambodia and Thailand were under extreme duress. There was just a huge volume of water that was being held back in China.” 

Today, the Chinese section of the river in the southwest of the nation has 11 damns, which produce more power than the region needs. These water reserves in China are swelling, as dam reservoirs fill with the glacial melt that has fed into the River for thousands of years.

Basist says, “Glaciers are bank accounts of water but with climate change they’re melting fast. The Chinese are building safe deposit boxes on the upper Mekong because they know the bank account is going to be depleted eventually and they want to keep it in reserve.”

Since China doesn’t have any formal water treaties with countries in the lower Mekong regions, cooperation between the countries is poor. The Mekong River Commission works with the governments of Laos, Cambodia, Thailand and Vietnam, but China is noticeably absent.

Sea-level rise is threatening West Africa. Growing stronger by the year, the tides push wave after wave into cities and villages, decimating dwellings and farmlands.  

The western coast of Africa, stretching more than 6500km from Mauritania to Cameroon, is in peril. Caused by global warming, rising sea levels are causing massive erosion — in some places eating away more than 30 metres of land in a single year.  

The more frequent occurrence of damage caused by rise in sea level affects different communities in specific ways, depending on population size, wealth, and geography. Governments and transnational organisations need to prepare contextualised response plans for affected communities.

West Africa Sea Level Rise

Sea levels are expected to rise by more than 76 cm around the world by the end of this century, but they are expected to rise faster than the global average in west Africa, where the coastal areas host about one-third of the region’s population and generate 56% of its GDP. A recent World Bank study shows that flooding and coastal erosion due to sea-level rise cost the region about $3.8 billion and cause 13,000 deaths in just one year.  

Ghana — the fastest growing economy in the world — is among the worst affected countries in the region. Coastal erosion at its 580km coastline comprising of sandy beaches and outcrops has consumed areas like Keta, Ada, and Shama. Rising temperatures have triggered the migration of fish stocks while salinisation has contaminated farmlands and freshwater reserves affecting the livelihoods of millions of fishermen and farmers. Frequent inundation has led to the destruction of commercial buildings, houses, and even human lives. 

Once a thriving trading hub, Ghana’s Keta city has suffered massive coastal erosion in recent decades that forced more than half of the population to flee. Fuveme — a coastal village in Keta that lies between the Gulf of Guinea and the Keta Lagoon — has already been reduced to an island forcing thousands of families to migrate to the inland. 

Senegal, another west African country, has been witnessing the devastating effects of sea-level rise this decade. The country’s famous colonial city Saint-Louis — a UNESCO World Heritage site with a population of 300,000 people — is seeing houses destroyed, streets flooded, and crops damaged by the encroaching saltwater.

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Encroaching waters off the coast of west African countries are destroying homes, schools, farmlands, and a way of life.

Perched at the edge of the Atlantic Ocean and at the foot of the Sahara Desert, the city is vulnerable to the rising sea because nowhere in the city is higher than 4 metres above the sea level. Rising tides have led to serious coastal erosion and forced schools, mosques, and hundreds of houses to be evacuated. Seawater has decimated crops that once thrived on the freshwater flow from the Senegal River.  

Nigeria, the most populous country in Africa, too has low lying cities that are being destroyed by the sea. Its most populous city Lagos, a megacity located next to the Atlantic Ocean, consists of a mainland and a series of islands with an estimated population of 21 million. A large number of city residents who live on waterfront slums with no proper drainage or water systems have been suffering due to rising sea levels as their dwellings get flooded frequently.

Other west African countries such as Benin, Cote d’Ivoire, and Togo face a high rate of coastal erosion. A World Bank study reveals that 56% of the coastline in these countries has been eroding 2 metre per year. Damages from the sea-level rise cost the government of Cote d’Ivoire nearly $2 billion — 4.9% of its GDP, while it cost the Benin government $229 million — 2.5% of the country’s GDP. 

Tackling Climate Change in West Africa

It would require hundreds of billions of dollars to protect cities and villages from sea-level rise in West Africa. Costs will continue to increase in the future as sea levels rise and populations in the coastal areas grow. But, most countries cannot afford sea-level rise adaption strategies as they are already struggling with immediate poverty challenges. 

However, there are external financial sources the west African governments can depend on.  One of them is international climate funds disbursed among the countries struggling with issues caused by climate change. 

Governments should direct funds towards education and agricultural strategies that are adaptive to environmental changes. Farmers can employ strategies such as floating cultivation, crop rotation and seasonal water management. Ultimately, states should begin to invest in programmes involving a managed retreat for rural coastline residents. States must facilitate these migrations by incentivising people to move early. Governments can expand public transportation between inland and coastal settlements, so that individuals who move inland can continue to work on the coast for as long as possible, or vice versa. Delaying relocation until the conditions become untenable can be traumatic for communities and local economies. A comprehensive managed retreat programme can be the most efficient way for communities to maintain economic output over time.

The legal dispute over the Silala river shared by the Plurinational State of Bolivia and the Republic of Chile before the International Court of Justice provides an enlightening example of the growing and complex interaction between climate change, water scarcity and international water law. Since 1997, Bolivia has claimed that the watercourse, which derives from Bolivia and crosses into Chile, belongs exclusively to Bolivia and is not international. Conversely, Chile insists it has a legal right to use the water and asserts the Silala is an international river. For international water law to apply, an international watercourse must be naturally occurring; however, Bolivia claims that the disputed river would not run to Chile without man-made canals constructed in the early 1900s. Hence, in Bolivia’s view, the Silala is not a natural transboundary watercourse. As international water law cannot apply, Bolivia states it can exploit its waters exclusively. The river meanders through one of the driest parts of the world, which strengthens the desire of both countries to claim rights over its use. This dispute is emblematic of a wider global problem. Water scarcity due to climate change and increased consumption are straining freshwater supply, opening the floodgates to a more assertive water-driven foreign policy and international posturing by nations.

The Silala River Dispute: “The most vulnerable basin on the continent”

The Silala is a current example of how political, socio-economic and environmental forces fuel competition for resources. The concept of “hydropolitical vulnerability”, defined by the United Nations Environment Programme as the “risk of political dispute over shared water systems”, is illustrated by the Silala dispute. 

It all begun in 1908, when Bolivia granted a concession to the Chilean Antofagasta-Bolivian Railway Company to use the waters of the Silala. Water, a scarce resource in the Atacama Desert, aimed to power steam engines that traveled between the cities of Antofagasta in Chile and Oruro in Bolivia. Bolivia claims that Chile built up canals that moved the river’s natural flow artificially from Bolivia to Chile. In 1962, steam-powered engines were replaced by diesel engines and water was no longer needed to power the latter. Since then, Chile has retained control of the water course, channelling its flow to supply mines and towns, even though the concession was initially given to power locomotives only. The Bolivian government revoked the concession in 1997 and sought to charge Chile retroactively for these diverted uses of the Silala waters. 

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Historical friction and the lack of full diplomatic relations between Bolivia and Chile since Bolivia’s loss of access to the Pacific Ocean in the War of Pacific at the end of the nineteenth century, strengthens the disagreement between the two countries over the Silala. 

Bolivia’s hope to gain access to the sea vanished on October 2018 after the International Court of Justice ruled in support of Chile which is not required to negotiate the surrender of its territories to give Bolivia access to the Pacific coastline. The ruling is a significant defeat for the Bolivian president Evo Morales and weakens its re-election bid. Hence, because of the underlying geopolitical and economic issues, the Silala has become one of the most vulnerable basins in the world. 

Geopolitical and Natural Challenges to International Water Law

In June 2016, the United Nation’s highest court, the International Court of Justice (ICJ), has assessed a legal case concerning the Silala river. The lawsuit is still ongoing. On the one hand, Bolivia claims ownership of the Silala as the river originates from springs on its territory. The country believes it can exploit the river and charge the riparian State for its use. On the other hand, Chile insists it has a sovereign right to the Silala, an international watercourse which had never been diverted from its springs but instead naturally canalised. The applicability of international water law to the Silala case depends on whether or not the Silala River is described as a natural transboundary watercourse. Human-altered canalisation and flow deviations would not fall within the rubric of international water law. 

Should the river be considered an international boundary, it would prevent Bolivia from using the river’s waters without sharing them with Chile. It would, instead, entail an equitable utilisation of the watercourse as well as a duty of cooperation with its neighbour. These principles have been codified in the 1997 United Nations Convention on the Law of Non-navigational Uses of International Watercourses whose fifth article states that “watercourse States shall participate in the use, development and protection of an international watercourse in an equitable and reasonable manner. Such participation includes both the right to utilise the watercourse and the duty to cooperate in the protection and development thereof”. Hence, Chile would have the right to a “reasonable and equitable” share of the river. It is noteworthy that Bolivia has not ratified the Convention.

Instead, Bolivia argues for its supreme sovereignty over the use of the Silala. Bolivia’s view might well refer to the Harmon doctrine, a principle stating that, in the name of the absolute sovereignty over its natural resources, “an upstream country has the unrestricted right to use the water of an international river irrespective of downstream consequences”. Yet, Bolivia’s argumentation is not based on this doctrine but rather on the qualification of the Silala as a domestic and not an international one, which enables the country to refuse any obligation towards Chile.  

International law may not have a solution to a political problem. Furthermore, the human right to water may relativise the relevance of the legal qualification of the Silala river as a domestic or an international watercourse. Bolivia may have extraterritorial obligations towards the riparian State as its absolute right to use Silala waters might have consequences on people living in Chile who rely on the Silala for domestic uses. Negotiations between the two countries remain a back seat while the lawsuit continues, although talks may come to the most optimal solution for this hydro-politically vulnerable basin.  

Water is a Scarce Resource in the Region

The Silala dispute highlights that water is an increasingly contentious resource, as a result of climate change and increased demands from population and industry. In 2016, Bolivia found itself in a national state of emergency due to a drought brought by a very intense El Niño. Even in unexceptional circumstances, Bolivia and Chile regularly face drought-induced water shortages. 

The Silala flows across the Bolivian-Chilean border in the Atacama Desert, one of the driest places in the world. The Atacama receives 15 millimeters of rain on average per year. Underground water basins around the desert are depleting due to excessive exploitation. Intensive mining activities in the region are severely straining available water resources. In Chile, water is considered an economic good,  bought and sold on a private water market at a relatively low price, with little governmental regulation and management. Mining companies can buy as many water contracts as they want. This cheap resource is not considered as an important capital until it is run out.

According to Dieter Helm, an economist and Professor at the University of Oxford, natural resources, such as water, should be considered a form of “natural capital” to be valued alongside human and financial capital, with an intrinsic economic price, not just as an unpriceable necessity. If natural capital keeps being provided for free, the argument goes, people, companies and governments will not have any incentive to moderate their use. Pricing natural capital as well as damage to it, would represent a viable solution, placing water at the centre of economic and political future of the Atacama region.

 Bolivia has recognised the climate crisis as one of the top risks for the country’s future. Its population is rising, while the Andean glaciers that don its high peaks are shrinking dramatically. According to a study published in The Cryosphere, a European Geosciences Union scientific journal, the glaciers of Bolivia shrank by 43% between 1986 and 2014. Glaciers are in retreat as the world warms, a consequence of rising levels of carbon dioxide in the atmosphere in response to the increasing combustion of fossil fuels. Shrinking glaciers will significantly impact downstream communities that are dependent on meltwater from glaciers, particularly during the dry season. Increasing temperatures and river streamflow reductions will make rural people increasingly vulnerable in areas already plagues by antiquated farming methods and poor yields. 

River-related conflicts are becoming one of the leading causes of tension between countries that suffer from water scarcity and global warming. The Sialala transboundary freshwater dispute, intensified by extreme droughts, shrinking glaciers and management challenges, has the potential to escalate antagonisms in the Andean region. The issues that ground this typical case expand beyond water rights. They involve a competition for resources, strengthened by water scarcity. Hence, while there may be water rights at stake before the International Court of Justice, the Silala dispute is also concerned with allocating economic and political interests in a situation of climate crisis scenario. Water scarcity in both countries is likely to intensify claims of absolute territorial sovereignty over the river instead of promoting adroit management and equal rights. The outcome of this legal case may be crucial to future Chile-Bolivian relations. 

This article is part of a series published jointly with Global Risk Insights (GRI) a leading geopolitical online news-source. Our aim is to explore the deep links between a changing climate and geopolitical shifts, to highlight how the impending climate crisis is already starting to unravel the delicately achieved balance of international power. Furthermore, the series aims to lay bare the impacts the climate crisis will have on the global fabric of society, the global economy and the domestic stability of our nation states.

Research suggests that groundwater reserves in sub-Saharan Africa are more resilient to climate change than previously understood. But overexploitation by humans could still dwindle them.


Previous studies that indicated climate change caused rapid depletion of groundwater — the largest source of freshwater resource on the planet — had raised serious concerns among climate scientists and conservationists. But new research by a consortium of international hydrogeologists suggests that climate change may not deplete groundwater in sub-Saharan Africa.

The study — the first regional assessment to look at how climate change has influenced groundwater across sub-Saharan Africa — examined patterns of groundwater replenishment in 14 multidecadal groundwater level records from nine African countries that represent a range of climates from hyper-arid to humid. Researchers found that groundwater was consistently replenished every year regardless of the amount of annual precipitation. The replenishment process has been more sensitive to the intensity of rainfall than to the overall amount of rain.

Although the climate crisis is expected to cause less overall rainfall, the research suggests that groundwater supplies in Africa will survive because of the heavier and more intense rainfall caused by global warming. Even if annual rainfall is low, periods of intense rain will be sufficient enough to replenish local groundwater resources.

Groundwater Levels in Africa

In Africa, groundwater reserves are 20 times larger than the water stored in lakes and reservoirs above ground. A vital source of drinking water for millions of people in cities and villages across the continent, these reserves are accessed through wells, boreholes, and springs. People rely more on them during droughts than other water sources on the surface, which often remain dried up during the summer.

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Multi-decadal groundwater levels across Sub-Saharan Africa show that groundwater recharge due to intense periods of rainfall.

The researchers determined groundwater levels analysing a relative balance between recharge — the process by which groundwater is replenished — and discharge — the flow of groundwater to springs, streams, wetlands and the sea. Individuals and companies collecting water for irrigation and drinking also contribute to reducing the amount of stored groundwater.

A comparative analysis revealed that groundwater is mostly replenished by rainfall that trickles down through the soil to the water table in wetter regions of Africa. This phenomenon occurs consistently across large areas on the continent. But in drier regions, groundwater is mostly recharged locally by water leaking from temporary streams and ponds, which usually start overflowing after heavy rains.

Scientists consider these findings path-breaking because previous studies had ignored an important fact about groundwater replenishment. “Previous regional-level assessments of groundwater resources using large-scale models had ignored the contribution of leaking streams and ponds to groundwater supplies, underestimating its renewability in drylands and resilience to climate change,” says co-lead of the study Dr. Mark Cuthbert from Cardiff University.

Those studies based on computer models had earlier predicted that freshwater will become scarcer in African drylands as climate change continue to reduce rainfall. But, the reality appears to be the opposite as per these findings: global warming is making rainfall come in fewer but heavier bursts accelerating overall groundwater replenishment. 

These findings debunk myths of groundwater depletion in Africa and will encourage policymakers to adopt new strategies to meet the United Nations’ Sustainable Development Goals (SDGs) like food security and access to clean water. Food production on the continent can be improved by allocating groundwater for irrigation through sustainable resource management, which can also ensure safe drinking water for generations to come.

With many rivers dwindling and the groundwater in India nearly exhausted, an acute water scarcity crisis is underway in the world’s second-most populous nation.

Causes of Water Scarcity in India

Taps have run dry in India as millions of people brace themselves for the dreaded blend of extreme heat and water shortages during the summer. A combination of climate change, inefficient water use, and inadequate infrastructure has thrown India into a full-blown water scarcity crisis, forcing the government to create a brand new ministry–‘Jal Shakti Ministry’–to tackle the issue.

Water Scarcity in India: Statistics

This year, more than 330 million people are affected due to water scarcity as half of the nation’s land area grapples with drought-like conditions. 12% of the population, majority of them living in metropolitan cities like Bengaluru, Chennai, Delhi, and Hyderabad, are already facing the ‘Day Zero’ scenario, wherein most of their water supplies came to a complete halt. As many as 21 major cities including the national capital–New Delhi–is poised to run out of groundwater next year, according to a report by government-run think tank NITI Aayog. 

By definition, India now is a water-stressed country, where annual per capita water availability is below 1500 cubic metres. Half a century ago, it was 5200 cubic metres.

An assessment by the government indicates that the nation is gradually inching towards a calamity with the annual per capita availability likely to drop below 1000 cubic metres.

Climate change has pushed India’s climate towards extremes disrupting the quantity and frequency of rainfall. The country witnessed below average monsoon for the last two consecutive years. The North-East monsoon which provides 10-20% of India’s rainfall was deficient by 44% in 2018 as per data from the India Meteorological Department (IMD). This compounded the rainfall deficit in the South-West monsoon that provides 80% of the country’s rainfall, which fell short by 10% last year. Lower rainfall has reduced water levels in reservoirs across the country. During the first half of this year, 91 major reservoirs recorded 32% drop in their water capacity.      

Chennai, a coastal city of 10 million, had 55% less rainfall this year. The city went without rain for 200 days with its four water reservoirs turning into puddles of cracked mud causing the worst water scarcity crisis in 70 years.

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Puzhal reservoir in Chennai, India, has been reduced to a dry lake bed in just one year.

Unusual temperatures caused by climate change have made rainfall erratic with significant changes in monsoon patterns making droughts and floods more common in many parts of India. In 2015, a massive flood, spurred by unusually massive rainfall, devastated Chennai killing more than 500 people and leaving the city ravaged. Last year, flash floods in the states of Kerala and Karnataka caused distress while cyclones wreaked havoc in Tamil Nadu and Odisha.

India is rated ‘high risk’ in the Climate Change Vulnerability Index with major Indian cities are projected to experience a higher number of consecutive drought days with less rainfall in the near future. Changes in temperature, precipitation, and humidity will significantly impact the quality and quantity of water across the country, where water resources are also under unprecedented pressure from population growth, rapid urbanisation, and inefficient water use.

The water scarcity crisis is not unique to India. Globally, over 880 million people–about one in every nine people in the world–do not have access to clean water within 6 km of their homes. The United States Agency for International Development (USAID) predicts that approximately one-third of the world population will face chronic water crisis by 2025.

Freshwater constitutes only 2.5% of the total water on our planet and much of it is trapped in icecaps and glaciers, making it inaccessible for us. In reality, a meagre 0.007% of the planet’s total water is available to feed its 7.7 billion people.

India Water Crisis: Solutions

To avoid the impending water crisis, India and other vulnerable countries need effective climate change adaptation strategies that reflect the importance of water management in reducing vulnerability and building climate resilience. It is also necessary to bring in technology to help harness water more efficiently and build long-term water conservation plans.

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Agriculture accounts for around 70% of all water withdrawals globally according to the World Bank, and approximately 60% of that is wasted, largely due to inefficient applications according to the UN’s Food and Agriculture Organisation (FAO). With water increasingly valuable against the backdrop of a rising human population and climate change, can AI be used to prevent water wastage? 

Simple techniques like rainwater harvesting and wastewater recycling are already being used in many regions to reduce water consumption. And many farms have realised the benefits of replacing their surface and sprinkler irrigation systems with more efficient drip irrigation systems.

But there’s another technology that could provide much bigger benefits to farms the world over: Artificial Intelligence.

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Global water stress map (Courtesy of TheCropSite)

How can AI solve climate change?

An Italian startup, Blue Tentacles, has come up with a “precision based” AI system that takes note of humidity, temperature, climate data and forecasts as well as satellite data to help farmers improve their irrigation practices whilst preventing water wastage and conserving energy.

In Japan, similar digital farming solutions collect data from soil and light sensors to advise on the quantity of water and fertilisers required. This is particularly useful to inexperienced farmers who might need help to improve productivity while reducing water consumption. These digital technologies are already being used by a number of large scale company run farms in Japan like GRA Inc, a strawberry farm that has gained a competitive edge by embracing technology.

A fuzzy logic system developed in Cordoba Spain, assesses and predicts the varying water needs of different users (for example, different crop growers in an association). This allows farming associations to not only manage water supplies more efficiently, but also to schedule maintenance and repair tasks, hire staff and manage electricity usage more effectively.

ConserWater tracks how water is distributed in a field using satellite and historical data. This allows users to fine tune their irrigation supply and also identify any leaks in the irrigation pipes. Their AI system can learn to identify damaged areas in a pipe without the need for manual inspection. It is a scalable solution working without ground sensors, and farmers would only need a desktop or a smartphone to access the data and receive notifications. Their products are being used by a 100+ farmers across the globe.

The fight to preserve freshwater extends beyond bucolic countryside hedges spilling into hydro-supply monitoring. UK-based United Utilities has partnered with Emagin to develop AI to manage their water networks and plan to test the technology on leakage reduction.

Similarly, WINT Water Intelligence in the US has developed an AI system to analyse water flow in residential and commercial buildings, identifying faults, waste and leaks and, if needed, shutting off a water supply to prevent damage. While this system has been designed for commercial facilities and manufacturing industries, similar solutions could be exported to the farming sector.

The agricultural sector is primed for disruption, from automating the analyses of aerial imagery of a field to identifying crop stress, weather forecasts and supply-chain optimisation. But how to ensure global wide-scale adoption?

Granular data collection for each farming zone is key and governments should facilitate it as much as possible. Data is the backbone for any AI system and the sooner it is collected the more historical data will be available for calculations.

Providing tools and training to farmers is equally essential. In 2017, when India collaborated with Israeli scientists and agronomists to establish drip irrigation in the country, teams of specialists educated local farmers through seminars and field visits to smooth the shift to new tools and practices.

Also in India, Microsoft collaborated with ICRISAT (International Crops Research Institute for Semi Arid Tropics) developing a predictive analytics app that calculated the best crop sowing date for maximising the yield. As a test case, farmers across seven villages were sent text messages with dates for sowing and other advice. Despite meager rainfall, farmers that used the app boosted their yields by 30%. When other farmers witnessed the results, they were also more likely to use the app themselves.

Introducing new methods and sophisticated machinery is expensive and would require tax breaks and financial support. This could come in the form of private sector grants like Microsoft’s AI for Earth Grant or through government policy. Funding would also be required to ensure adequate testing of the technology in the farms once it is developed.

Preventing water wastage  is not an intractable issue but whatever new AI tools or systems are devised, widespread public awareness and adoption should be a top priority. The OECD projects that Northeast China, Northwest India and Southwest USA are fertile grain belts supporting millions of people but also areas on the verge of imminent water scarcity.

Featured image by jcomp/ Freepik

Are we running out of water? Only 3% of the water on the Earth’s surface is freshwater. Less than 0.5% of that is accessible for consumption as drinking water. If no urgent action is taken, an increasing number of cities worldwide are expected to experience severe water shortages. Recent analyses by the BBC ranked cities such as Beijing, Tokyo and London among those most likely to run out of drinking water in the near future.

Is the World Running Out of Water Because Climate Change?

The short answer: yes. Climate change is expected to severely alter the quantity, quality and spatial distribution of global water resources. Warmer temperatures increase evaporation, change the holding capacity of moisture in the air and alter rainfall patterns. The most recent IPCC report concluded that, in general, wet regions will get wetter and dry regions will get drier. Increases in the frequency and intensity of extreme events like droughts and heatwaves will also contribute to water stress and water shortages.

A ground-breaking study on the impacts of climate change to groundwater resources was recently published in Nature Climate Change. The study showed that groundwater stored in aquifers, which provides 36% of the world’s domestic water supply for over 2 billion people, is highly sensitive to future climate change.

Groundwater is stored in underground aquifers that are replenished by rainfall and soil moisture. Could this groundwater be depleted, and if so, when will the world run out of water? Researchers found that 44% of all aquifers globally will be fully impacted and depleted as a result of climate change in the next 100 years due to changes in the intensity and pattern of rainfalls. Underground water reserves in drier regions are naturally slow at adjusting to above-ground atmospheric and climactic changes, but over-abstraction and other impacts of extreme drought may still exacerbate regional water shortages. 

You might also like: Water Scarcity: How Climate Crisis is Unfolding in India

Figure 1: Groundwater response time: measure of the time in number of years it takes a groundwater system to re-equilibrate (replenish and discharge into rivers, lakes or streams) to changing conditions

Another recent study concluded that total water storage in landlocked river basins has declined significantly over the past few decades. Using gravity satellite observations from the NASA GRACE satellite, researchers calculated that water storage is declining by 100 billion tonnes per year, which is attributable to climate change and unsustainable water management. Given that most of the landlocked basins are in arid regions, there are significant implications to regional water stress.

A consequent impact of water storage decline is its contribution to sea level rise. Because of conservation of mass in the earth system, water lost in landlocked basins impacts global sea level through changes to the water vapour flux. Water loss in landlocked river basins accounted for about 10% of global sea level rise observed in the past 10 years.

Figure 2: Total water storage change in mm per year in global landlocked river basins

Why is the Water Cycle Important in Preventing the World Running Out of Water?

There is a growing consensus around the idea that anthropogenic climate change is already significantly changing the global water cycle and that the sustainability of freshwater sources is being compromised.

Urbanisation and an exponential increase in freshwater demand for households are driving factors behind water shortages, especially in regions with a precarious water supply. Cape Town, the first modern city to effectively run out of drinking water in 2018, has suffered because of the confluence of extreme drought, poor water resource management and over-consumption. Pipes were dry and thousands were left queuing for drinking water. Similarly, China is also at risk of running out of water; the total renewable water resources per inhabitant is 2 018 cubic meters each year- 75% less than the global average, according to the World Bank.

Disruptive technologies like artificial intelligence and machine learning may hold the key for new and bold solutions. Smart hand-pumps that leverage AI to analyse groundwater use and predict pump failures has been experimented in rural Kenya resulting in water use optimisation and thus reducing wasteful dispersion of this increasingly precious, liquid gold.

A smart grid water management approach with an Internet of Things (IoT) system could be the answer. An IoT system refers to a network of physical objects that have been embedded with communications software, wireless environmental sensors, and automated control systems. An IoT system can monitor structural integrity and environmental factors, and can communicate with the rest of the system to perform real time risk analysis. IoT infrastructures have been highly successful in optimising the efficiency of wind and solar power farms by minimising risk and redundancy and maximising output. A water management IoT system can monitor air, water, and soil conditions autonomously and waste can be reduced via timely responses to weather events and water demand. Governments should invest in IoT research with a view towards significant long-term savings and increased efficiency in water management.

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