A Public lecture on “The Science of Climate Changes” by Dr J. Srinivasan was held at the CDS on October 16, 2017. In his welcome address, Prof Sunil Mani described Dr Srinivasan as a distinguished scientist of the Divecha Centre for Climate Change and honorary professor at the Centre for Atmospheric and Oceanic Sciences, IISc, Bangalore, having published more than 130 journal publications in the area of monsoon models, climate and solar energy and climate change. Prof Mani also thanked Prof Manmohan Agarwal for suggesting that the CDS needs to move away from pure economics to other subjects like climate change and similar topics for lectures held at the CDS.
Dr Srinivasan stared his lecture by stating that climate change is one of the most challenging problems in the 21st century. Climate is the long-term statistics of weather. Climate is usually determined by averaging temperature, humidity, rainfall, winds and other atmospheric and ocean parameters over a 30 year period. If there is a large change in these parameters between two 30 year periods, then one can talk about climate change. In recent years, climate change is usually associated with human-induced climate change. Climate change can also occur due to natural causes.
The lecture mainly focused on three aspects of climate change – climate change in the past, the present and how this will influence the 20th century, and finally the future which will be based on prediction of models. Climate changes that have occurred in the past were caused by variations in earth-sun geometry or volcanic eruptions. The study of the past climates has provided valuable insights into the factors which control earth’s climate. In the 20th century, the earth’s climate was influenced both by natural variations and those induced by human actions. The human-induced changes are those caused by the release of carbon dioxide and aerosols during the burning of fossil fuels. In the 21st century, human-induced changes are expected to dominate over natural variations.
Prof Srinivasan also cited an incident wherein a major chunk of ice had broken away from a glacier which could drastically affect climate change in a big way, leading to flooding events and river flooding. He pointed out that in Kerala deforestation has been rampant in the last ten years; this is also seen in the Amazon forest which is also on the verge of disappearing. To prevent adverse impact of climate change, the human civilization has to move away from a society dependent on fossil fuels to one that depends primarily on renewable energy sources. Solar and wind power have given a dramatic boost to renewable energy technology. To bring about this transition in the next 20 years, there will be need for a great political will and a commitment to the welfare of future generations.
The floor was then thrown open for an informal interactive session with students, research scholars and those from the audience. At the end of the discussions, Prof Sunil Mani thanked Dr Srinivasan for the wonderful lecture and mentioned that a complementary lecture on Water Governance in India would also follow in December this year.
