Global Drought Outlook

Syllabus: GS3/ Environment

Context

• The Organisation for Economic Co-operation and Development (OECD) has released its Global Drought Outlook, highlighting the increasing frequency, and geographical spread of droughts globally.

What is drought?

• Droughts are periods characterised by a significant hydrological imbalance in water sources or reservoirs, typically marked by “drier-than-normal” weather conditions. 
• These periods are primarily driven by low rainfall and can be further intensified by high temperatures or strong wind, which accelerate water evaporation, as well as human activities.
• Classification:
  • Meteorological drought refers to a prolonged period of low precipitation. 
  • Agricultural (or ecological) drought refers to a condition where soil moisture is insufficient to meet the needs of crops and vegetation. 
  • Hydrological drought occurs when surface or groundwater water levels drop below average over a prolonged period. 

Key Findings

• The global land area affected by drought doubled between 1900 and 2020, with 40% of the planet experiencing increased drought frequency and intensity in recent decades.
• Since 1980, 37% of global land has experienced significant soil moisture decline. Similarly, groundwater levels are falling globally, with 62% of monitored aquifers in decline.
• Climate change made the 2022 European drought up to 20 times more likely and increased the likelihood of the ongoing drought in North America by 42%.

Causes of Droughts

• Natural Causes: 
  • Climate variability, such as El Niño and La Niña, affects global weather patterns and can result in prolonged dry spells in some regions.
  • Reduced snowfall and melting glaciers diminish freshwater sources over time.
• Anthropogenic Causes:
  • Deforestation and land degradation reduce the soil’s ability to retain moisture and disturb the local water cycle.
  • Urbanisation leads to soil sealing, which prevents water infiltration and groundwater recharge.
  • Unsustainable agriculture and over-extraction of groundwater, especially through inefficient irrigation practices, worsen the drought intensity in some areas.

Impacts of Drought

• Environmental Consequences: Droughts severely degrade ecosystems such as forests, wetlands, and grasslands, leading to loss of biodiversity and reduction in plant biomass.
• Economic Consequences: Droughts also impact hydropower production, industrial operations, and fluvial trade, reducing efficiency and increasing energy and food insecurity.
  • The economic costs of droughts are rising globally by 3% to 7.5% annually.
• Social Consequences: They contribute to food insecurity, migration, water scarcity, and livelihood loss, especially among marginal and vulnerable communities.
  • Droughts account for only 6% of natural disasters but cause 34% of all disaster-related deaths.

Key Recommendations

• Investment in Drought Resilience: Every USD 1 invested in drought prevention yields USD 2 to 3 in benefits, with some resilience projects offering up to ten times the return on investment.
• Ecosystem and Land Use Management: Ecosystem restoration improves water retention and soil health. Drought-tolerant crops and adaptive farming help secure food systems.
• Cross-Sectoral Action: Include energy, transport, infrastructure, and urban planning in drought resilience strategies.
  • Irrigation efficiency improvements could cut global water use by 76%.

Source: OECD