GS Paper 1
Syllabus: Important Geophysical Phenomena
Context: According to a new study, flash droughts are becoming more common and faster to develop around the world, and human-caused climate change is a major reason.
|Difference between Flash & Conventional Droughts||Flash drought is the rapid onset or intensification of drought. It is set in motion by lower-than-normal rates of precipitation, accompanied by abnormally high temperatures (heat waves), winds and radiation. Typically occurs during warm seasons and tropical/humid places are more vulnerable||Conventional Drought is a slow-onset (natural) disaster characterised by the lack of precipitation, resulting in a water shortage.|
|Causes||Higher temperature increases evapotranspiration – the process by which water is transferred from the land to the atmosphere by evaporation from the soil and by transpiration from plants.
Flash drought can also be tied to rhythmic climatic patterns, such as El Nino (in Asia) and La Nina (eastern Pacific) events.
If not predicted early enough, changes in soil moisture can cause extensive damage to agriculture, economies, and ecosystem goods and services.
|Prediction and Mitigation||Changes in the rate of evapotranspiration and soil moisture have been identified as key early warning indicators.
Vulnerability mapping will help policymakers, and farmers plan accordingly.
Highlights of the study:
- Flash droughts occurred more often than slower ones in tropical/humid places like India, Southeast Asia, sub-Saharan Africa and the Amazon basin.
- As global warming continues, more abrupt dry spells could have grave consequences for the livelihoods of people dependent on rain-fed agriculture.
The interlinking of rivers can provide viable solutions to the multi-dimensional inter-related problems of droughts, floods, and interrupting navigation. Critically examine. (UPSC 2020)