Many of the climatic extremes that are happening the world over, like a sudden increase in rainfall or extreme hot or cold climate are part of climate change, said Surabi Menon, physicist staff scientist at the Lawrence Berkeley National Laboratory, California.
Speaking to The Hindu here while on vacation at home, Ms. Menon said the subject of extreme climate is one of the foci of the U.S. Department of Energy in atmospheric changes.
All the greenhouse gases and the aerosols that contribute to change in climate need to be controlled and it is not just enough to talk about less carbon-dioxide (CO2) emission, said Ms. Menon, who is one of the contributing authors to the Working Group I of the Intergovernmental Panel on Climate Change. The chapter relates to bio-geochemical sciences in the climate change report.
Each gas and particle is studied separately to make predictions. The dark particles among aerosols that absorb light are also responsible for differential distribution of light in an area.
How the presence of aerosols has affected the climate in China is evident in the laboratory as well as in real time, she said. Changes in the atmosphere sometimes give rise to extreme climate events, said Ms. Menon.
“Satellite images show intense pollution over India and China. There has been a marked change in climate from 1979 onwards in China”.
The kind of developmental activity that is taking place in India would have a factor of four degree decrease in rainfall by 2030, going by the current rate of pollution.”
Ms. Menon simulates climate modules for China and India in the Berkeley laboratory with the data she procures from various agencies from the two countries. The Chinese are meticulous in keeping their data, she said. A lot of data from over a long period had been analysed for the country, she said.
In India, data handling is rather inconsistent. But of late, there have been some good papers on climate and atmospheric sciences coming up from various centres of excellence, said Ms. Menon.
“We can construct the Earth’s climate history with paleo-climate record. If we put in good data to simulate climate modules, predicting climate becomes near-accurate”, she said. Going by the current rate of CO2 emission, 60 per cent of what has been released by human activity on Earth continues to stay in the atmosphere. Climate predictions are important to the process of formulating government policies that would help bring down the greenhouse effect, she said.
The polluting activities would otherwise lead to what is called the tipping point in the Earth’s climate that would happen when temperature goes up by 2 degrees centigrade. As of now, 2100 is predicted to be the tipping point when the sea-level rises because of the intense melting of glaciers.
