Climatic resiliency for Indian cities

Resiliency means springing back into normalcy after being stretched. Climatic resiliency of Indian cities are gradually becoming distant-goal to reach. Reason being the some of the climatic controls have been heavily doctored by urbanization. Climatic controls influence behaviour of the climatic elements like temperature, humidity, wind, rain, snow and radiation. Phenomena like Urban Heat Island (UHI), urban flood, etc. are quite regular phenomena now-a-days occurring in urban environment. Climate controls are many and their control on climatic elements is also of different types. The primary climatic controls are: latitude and altitude of any city, land and water body distribution, differential behaviour of the earth-surface with respect to insolation (incoming solar radiation), ocean current, prevailing winds, cloudiness, slope and valley, etc. To elaborate the issue an example of UHI in Central Business Districts (CBDs) can be cited; temperatures in CBDs are always 5 to 6 deg C higher and the situation is getting aggravated due to increase in hard-covered surfaces. Hard-covered surfaces have different albedo, specific heat, thermal conductivity, transparency, rate of evaporation in comparison to natural earth surfaces and thus causing differential outgoing terrestrial re-radiation. This adds up heat in presence of increased number of pollutants. Indian cities are located in various climatic zones; namely hot-arid, warm-humid, coldhumid, cold-dry and composite. To recreate urban resiliency, we have to set a benchmark standard which supposedly be individual for every city and should indicate the condition which was existing at the earlier stage of urbanization. This presentation is based on a paper that delineates the climatic control issues and their impact on climatic elements individually and as a whole. Distortions in the present-day climate will are referred with examples. And it also suggests some solutions, both medium- and long-term to improve cities' climatic resiliency.