Context: Parliamentary panel for synergy between IMD and private players
More in the news:
- According to the Standing Committee on Science:
- There is a need for better synergy between the India Meteorological Department (IMD) and private forecasters.
- To avoid confusion, especially during extreme climate events like cyclones or flash floods.
- Currently, there are three private players in India i.e.;
- Skymet (India),
- Earth Networks and
- IBM Weather.
- In recent years, the IMD and Skymet have often made differing predictions on the monsoon.
- In June 2021, the Kerala government, dissatisfied with the IMD’s performance, hired Skymet Private Limited, Earth Networks and the IBM Weather Company.
- In order to use ensemble predictions to improve extreme weather alert services in the State.
- The IMD was vociferous on the issue and said that multiple predictions often create unnecessary confusion.
- The members of the committee also expressed that, year after year, the IMD assesses the monsoon to be normal though the actual experience is different.
- Statistically, the monsoon may be normal in terms of the average rainfall, but most certainly the number of rainfall days had decreased.
- There have also been far more flash floods in recent times than ever before, the members pointed out.
- The committee also discussed:
- Flash floods are characterised by very fast rise and recession of flow of small volume and high discharge.
- It can cause high damages because of suddenness.
- A flood caused by heavy or excessive rainfall in a short period of time, generally less than 6 hours.
- This occurs in hilly and not too hilly regions and sloping lands where heavy rainfall and thunderstorms or cloudbursts are common.
- Geomorphically low-lying areas: washes, rivers, dry lakes and basins.
- Reasons for the cause of Flash Flood:
- It may be caused due to heavy rain associated with :
- A severe thunderstorm,
- A tropical storm, or
- Meltwater from ice or snow flowing over ice sheets or snowfields.
- Flash floods may occur after the collapse of a natural ice or debris dam, or a human structure such as a man-made dam.
- In areas on or near volcanoes, flash floods have also occurred after eruptions, when glaciers have been melted by the intense heat.
- Factors impacting the speed of Flash Flood:
- The intensity of the rainfall,
- The location and distribution of the rainfall,
- The land use and topography,
- Vegetation types and growth/density,
- Soil type, and
- Soil water-content
Flash Flood in India:
- WMO estimates that flash floods account for 85% of flooding incidents across the world, leading to around 5,000 deaths every year.
- At present in India, the Central Water Commission (CWC), which monitors dams, warns of rising water levels in water reservoirs, which are usually taken to be signs of imminent floods.
- Recently CWC has recently tied up with internet giant Google to develop software applications to visualise rising water levels during heavy rains.
The past incidents of Flash Flood in India:
- 2012 Himalayan flash floods
- 2013: Uttarakhand, Uttarakhand.
- 2013: Kedarnath, Uttarakhand.
- 2014 and 2018: Srinagar, Jammu & Kashmir.
- 2017: Uttarakhand, West Bengal, Bihar and multiple states in the North East.
More about NDMA guidelines for Flash Floods.