Facts for Prelims (FFP)
Source: DTE
Context: A recent study published in the American Meteorological Society’s Journal of Hydrometeorology reveals that peninsular river basins in India, including Narmada, Mahanadi, and Godavari, face a higher likelihood of widespread flooding compared to transboundary rivers like Ganga and Brahmaputra.
- The Narmada basin has the highest probability (59%) of widespread flooding.
- Other basins with notable probabilities of widespread flooding include Mahanadi (50%), Godavari (42%), Krishna (38%), and Cauvery (19%).
- Ganga and Brahmaputra, as transboundary river basins, have lower probabilities of widespread flooding, at 21% and 18%, respectively.
Reasons:
Drivers of widespread flooding are associated with atmospheric rivers, large atmospheric circulations carrying moisture from the tropics to extratropic. Events like the 2018 Kerala floods, the 2022 Pakistan floods, and the lower Mississippi River floods in 2008, 2011, and 2015–19 were linked to atmospheric rivers.
What are Atmospheric rivers?
They are long, narrow regions of the atmosphere that transport water vapour from the tropics to the poles. They can be 250–375 miles wide and over 1,000 miles long. When atmospheric rivers make landfall, they can contribute significantly to precipitation.
Difference between the Himalayan and Peninsular River System:
