INCREASING FREQUENCY OF MULTI-YEAR DROUGHTS WORLDWIDE

PRELIMS BITS

A recent 40-year study highlights the growing frequency and severity of multi-year droughts (MYDs), with significant impacts on ecosystems, agriculture, and water supplies. The study, covering data from 1980 to 2018, links the rise in MYDs to climate change, which intensifies drought conditions.

Key Points:

• What Are Multi-Year Droughts (MYDs)?
  • MYDs are prolonged dry spells lasting two years or more, leading to soil moisture depletion and reduced streamflow.
  • These droughts result in severe consequences for agriculture, ecosystems, and water resources, causing crop failures and increased tree mortality.
  • The study identified 13,176 MYDs between 1980 and 2018.
• Global Impact of MYDs:
  • The land area affected by MYDs has expanded by about 50,000 square kilometers annually.
  • The most impacted regions include temperate grasslands, with significant droughts in central Chile, the western United States, and parts of Australia.
• Notable Drought Events:
  • Five of the top ten most severe MYDs occurred between 2007 and 2018.
  • The eastern Congo basin experienced the longest MYD, lasting from 2010 to 2018, affecting over 1.4 million square kilometers.
  • The southwestern Amazon endured a nine-year MYD, with the peak impact in 2015.
• Influence of El Niño Events:
  • The study found a strong correlation between MYDs and El Niño events, notably in 1998, 2010, and 2015.
  • These events extended the reach of droughts beyond the tropics, affecting various global regions in the years following these El Niño events.
• Future Projections and Preparedness:
  • The study warns that multi-year droughts may become more frequent and intense in the 21st century.
  • It stresses the need for better preparedness and cooperative efforts to mitigate the impacts of these extreme events, highlighting the importance of adaptation strategies in response to the evolving climate.