Scientists warn that intensification and increased frequency of atmospheric rivers due to global warming is worsening extreme rainfall events and weather patterns.
Atmospheric rivers (AR)
- AR, also called as ‘flying rivers’, are relatively long, narrow regions in the atmosphere that transport most of the water vapour outside of tropics.
- An average AR is about 2,000 km long, 500 km wide and nearly 3 km deep.
- ARs are a part of larger system of extratropical cyclones that transport heat and moisture from tropics toward the poles.
- ARs are typically located within low-level jet, an area of strong winds in lower atmosphere.
- They are largest transport mechanisms of freshwater on Earth, responsible for 90% of moisture transfer from tropics to poles.
- While many ARs are weak systems, some larger and strong ARs can create extreme rainfall and floods, causing mudslides and catastrophic damage.
Climate Change and Atmospheric Rivers
- With temperature increase, intensity of rain events rises because of increase in atmosphere’s moisture retention capacity.
- By 2100, ARs are predicted to become more intense globally and will be much broader and longer.
- Intensified ARs can produce drought like conditions by removing rainfall from rainfall-dependent regions.
Impact of ARs on India
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