As Droughts Worsen Globally, Water Scarcity Likely to Grow For Agriculture

As Droughts Worsen Globally, Water Scarcity Likely to Grow For Agriculture

Drought and water scarcity in agriculture are expected to increase over time, according to two new reports.

Drought due to climate change is growing, says a United Nations report, while another study finds that water scarcity is expected to increase in areas where crops are grown by 2050.

According to the United Nations Convention to Combat Desertification (UNCCD) recent report, Drought in Numbers, 2022, since the year 2000, the number and duration of droughts has risen 29 percent throughout the world. Droughts make up 15 percent of natural disasters, but caused the most death, killing about 650,000 people from 1970-2019.

As Ibrahim Thiaw, UNCCD Executive Secretary noted that:

The facts and figures of this publication all point in the same direction: an upward trajectory in the duration of droughts and the severity of impacts, not only affecting human societies but also the ecological systems upon which the survival of all life depends, including that of our own species.

In a separate study published in Earth’s Future, scientists found that water scarcity for agriculture is expected to increase in more than 80 percent of croplands by 2050. The study’s authors assessed the water needs for agriculture worldwide, and then forecasted water availability, from both rain and irrigation, to determine whether water needs under climate change would be met. They found that with climate change impacts, agricultural water scarcity around the world will grow in up to 84 percent of cropland areas, with water supply loss increasing scarcity in about 60 percent of those croplands.

A unique aspect of this study is the development of an index that predicts agricultural water scarcity soil water from rain, called green water, and irrigation from streams, rivers, lakes and groundwater, called blue water. While typical of water footprint research, this is the first time such an index was used to examine global blue and green water scarcity due to climate change.

Food and climate change are commonalities between the sets of research. Besides actually losing water supplies from drought, drought hobbles agricultural production and removes food supplies that causes a rise in hunger, malnutrition and potentially even death. Thus drought is a common factor in agricultural water scarcity. As drought grows, so do water shortages, particularly as climate change exacerbates drought.

Fortunately there are ways to make societies and agriculture more resilient to drought and water scarcity. Interestingly, greater use of rainwater and soil moisture is pointed to in both sets of research, an often overlooked feature of resilience. Technologies like satellite-based early warning systems for drought that are quickly spread via mobile phones could alert people to low water supplies. For farming, utilizing more regenerative approaches to soil through mulching and no-till could store more water in crop roots, while harvesting more rainwater could store more water in cisterns or aquifers which reduces loss from evaporation. There are ways ahead to improve both water and food security if the threats—and opportunities—are taken seriously.

[Reuters and American Geophysical Union]