Speaking during a videoconference organized by the American Corner here with the US consul-general in Kolkata Helen LaFave on Earth Day on Wednesday, Sen said, "Knowledge and preparation are the keys to survival."

LaFave said the US government was committed to addressing the challenges of climate change in India. Several scholars presented their views and solutions on combating climate change and pollution.

Executive chairman of National Council for Climate Change Kirit N Shelat said the prime reason behind the climatic change in cities is the constant rise of carbon dioxide in the air. The development of cities and their expansion cut the green area, the natural absorber of carbon. It disturbs the nature's balance, he said.

Shelat also presented several solutions which can help the central government's plan of smart cities if government officials and individuals join hands to protect environment. "The government should make strict rules that every building should have green cover with solar power panel on its roof. It should also make provisions for recycling wastes and reusing their byproducts," he said.

Rajendra Agricultural University (Pusa) vice-chancellor RK Mittal talked about the benefits of agroforestry and recycling of food waste with students and volunteers present at the symposium. Recycled food waste not only helps in reducing land pollution but also can be reused if managed adequately as animal food, fertilizer, biogas, biofuel, paper and also as specific chemicals which can be used in different industries.