Study Throws Light on Flash Droughts

Recently, an international team of scientists has, by studying flash droughts between 1980 and 2015, mapped the global distribution, trends and drivers of flash drought occurrence. Key findings include:

• Global Hotspots: Flash drought hotspots exist over Brazil, the Sahel, the Great Rift Valley with local hotspots over the central United States, southwestern Russia, and northeastern China.
• Indian Scenario: India is a hotspot for flash droughts and this could have major implications on the country’s crop production.
• Summer Monsoon Flash Droughts in India: India could experience more flash droughts during the monsoon season than the non-monsoon season.
• Though soil moisture is replenished during the summer monsoon, a break in the monsoon along with high temperatures can quickly deplete the soil moisture.
• This rapid depletion of soil moisture results in flash droughts during the monsoon season.
• Forecasting Flash Droughts: Currently scientists are working on improving the predictability of these events, including the development of an early warning system.
• Impact: It is predicted that by the end of the 21st century, the frequency of concurrent hot and dry extremes in India will rise by about five-fold.
• This can cause approximately a seven-fold increase in flash droughts.
• Agriculture Sector: If a multi-week period of rapid drought development occurs, the agricultural sector can experience substantial economic losses and environments become more favourable for wildfire and heatwave development.
• About 10 per cent–15 per cent of rice and maize grown area in each year is affected by flash droughts during the monsoon season in India.
• Flash droughts during the monsoon season in India can directly affect crop production and indirectly pose challenges for meeting increased irrigation water demands.

Significance: Flash drought has significant impacts on agriculture, water resources, ecosystems, and the human environment. Addressing these challenges requires a fundamental understanding of flash drought occurrence. The current study is a step in that direction.

• The study points to the urgent need for India to have an adaptation framework in place to manage the available water resources and also explore the use of drought-tolerant varieties.