Water Storage Projected to Decline by Two-Thirds as Climate Changes

20 January 2021 Phoebe Sleet, Research Analyst, Global Food and Water Crises Research Programme

A study finds that the southern hemisphere will be especially at risk as terrestrial water storage falls, increasing the risk of violence within states.


A study published in January found that terrestrial water storage (TWS) could decline by up to two-thirds across the globe by the end of the 21st century, due to the effects of climate change. Alarmingly, the effects of decreasing TWS will lead to an increasing number of severe droughts, especially across the southern hemisphere, the United States and south-western Europe (East Africa and north Asia are projected to be exceptions to the trend and will likely see increased precipitation). Up to one in twelve people are projected to face severe drought by the end of the century as a result of this trend, compared to one in 33 at the end of the 20th century. Terrestrial water storage not only refers to the world’s rivers, but also includes groundwater, water stored in soil, snowpack, wetlands and other sources.


As the United Nations has pointed out, water is the primary way through which most people will (and in some cases already have) experience climate change, with consequences for health, sanitation, human productivity, agriculture and food security. The most obvious effects of climate on water security comes in the form of natural disasters. According to the United Nations Educational, Scientific and Cultural Organization, global floods and destructive rainfall events have increased by 50 per cent since the start of the 2010s and occur four times more often than they did in the 1980s. Storms and droughts also occur twice as often as they did in the 1980s. In total, floods and droughts (which account for most water-related disasters) impacted around three billion people and caused around US$100 billion ($129 billion) of damage over the last two decades. An increase in water-related disasters is particularly significant, as they are the most common type of natural disaster – water-related disasters accounted for 74 per cent of all disasters between 2001 and 2018.

Among the many negative effects of water insecurity is its potential to exacerbate conflict. While evidence for the much-heralded “water wars” of the future is fairly slim (between 1944 and 2008, there were only 44 violent conflicts between states that could be linked to water, 30 of which involved Israel and its neighbours), intra-state conflict is far more likely to involve water in some way. A direct link between water scarcity and conflict is disputed, but an indirect relationship between water insecurity and violence is likely. This is especially true in situations where water insecurity decreases food production, drives up prices, causes economic slowdowns or forces migration. This makes poorer countries particularly vulnerable to water-related violence: poor countries are already more vulnerable to internal conflict, which may worsen as water insecurity dampens economic growth. This, in turn, prevents governments from providing basic services, which can fuel grievances and urban migration, which can help to exacerbate violence. It also limits the state’s ability to respond to internal conflicts. Grievances related to poor drought management were widely credited as having helped spark Syria’s bloody civil war in 2011.

A number of water-related disasters have the potential to create or worsen conflict in the immediate future. In the September 2020 quarter, Kenya, South Sudan, Zimbabwe, Iraq, Afghanistan and Bangladesh were all identified by the Water, Peace and Security Partnership as being at risk of increased violence due to droughts, floods or poor water management (in the case of Iraq). If the authors of the recent study into the future of water insecurity are correct, the risk of violence and conflict within states could increase as water insecurity rises.

Any opinions or views expressed in this paper are those of the individual author, unless stated to be those of Future Directions International.

Published by Future Directions International Pty Ltd.
Suite 5, 202 Hampden Road, Nedlands WA 6009, Australia.