IMD launches portal to aid climate change mitigation in India

The Climate Data Service Portal shows a steep rise in mean temperatures across all seasons since 1996, highlighting the impact of climate change on India’s mean temperature trends

The mean temperatures have shown a steep rise across all seasons since 1996 over India with the sharpest trend recorded in the pre-monsoon season, shows India Meteorological Department’s latest offering—Climate Data Service Portal (CDSP).

Representational Image. (HT archive)

The data highlights the impact of climate change on India’s mean temperature trends.

The portal, launched on Tuesday on World Meteorological Day, has real time visualisation of meteorological data from across the country; climatological tables; visualisation of historical meteorological data including of monsoon rainfall pattern; mean temperature rise; and frequency of cyclones etc.

According to IMD, CDSP will help researchers and the government in climate change studies; planning and mitigation strategies; and offer early warning to people. Statistical analysis of meteorological data on the portal is still under development.

CDSP also offers climatological data for each station. For example, for Safdarjung station, the mean maximum temperature from 1981 to 2010 has been 35.3 degrees C (°C) and the highest temperature recorded in March at the station was 40.6°C on March 31, 1945. The mean wet bulb temperature recorded in June at 5.30pm is 25.4°C ; 27°C in July and 26.9°C in August—the three monsoon months.

Mean seasonal temperature across the country over the years (CDSP)

Wet bulb temperature is the lowest temperature to which air can be cooled by the evaporation of water into the air at a constant pressure. It is measured by wrapping a wet wick around the bulb of a thermometer and the measured temperature corresponds to the wet bulb temperature, according to a paper in Science Direct.

Meanwhile, this year, IMD’s theme for World Meteorological Day was “Oceans, Our Climate and Weather’ with scientists highlighting the ocean’s impact on weather and climate, especially during the El-Nino and La-Nina phases. The ocean is also a major driver of the global economy, carrying more than 90% of world trade and sustaining 40% of humanity that lives within 100 km of the coast.

“Oceans absorb the greatest amount of excess heat in the climate system over 90%, the land surface absorbs 2.3%, and the rest is absorbed by glaciers and other surfaces such as ice lakes. So, you can imagine the impact of oceans on meteorology. The sea surface temperatures are rising more rapidly than atmospheric temperature. Naturally, oxygen levels are depleting, and oceans are becoming acidic. El Nino Southern Oscillation episodes, for example, have a profound impact on weather conditions in US, India and many parts of the world,” said M Mohapatra, director general, IMD.

El Niño and the Southern Oscillation (ENSO) is a periodic fluctuation in sea surface temperature and the air pressure of the overlying atmosphere across the equatorial Pacific Ocean, according to the National Oceanic and Atmospheric Administration.

ENSO has a major influence on weather and climate patterns such as heavy rains, floods and drought. El Niño has a warming influence on global temperatures, while La Niña has the opposite effect. In India, for example, El Nino is associated with drought or weak monsoon while La Nina is associated with a strong monsoon and above average rains and colder winters.