KOLLAM: For Kerala, greenery has become a thing of the past. As green spots give way to concrete jungles, the state is already facing a range of micro-climatic changes. With scientists working on climate change predicting the possibility of the state being faced with ‘above normal heat wave conditions’ triggered by urban heat island (UHI), a major study on the micro-climatic changes in the state is on the anvil. The study to be undertaken by the Institute for Climate Change Studies (ICCS), Kottayam, will cover three major cities - Thiruvananthapuram, Kochi and Kozhikode.“In simpler terms, UHI means the increase in land surface temperature,” an officer with the Department of Environment told Express.
“The area hit by UHI will be a lot warmer than the rural areas surrounding it. One of the reasons for UHI is rapid and unplanned urbanisation.”According to the officer, the contributing factors for UHI include high specific heat capacity of building materials, blockage of wind due to buildings, reduction in vegetation and others.“As an area hit by UHI has worse air and water quality, it will also have an impact on the people living in it. The most vulnerable group is the sick and elderly as they will be exposed to the perils including heat waves,” he said.
Meanwhile, a scientist with ICCS told Express the reason for undertaking a study of this kind is to look into the impact of rapid population growth, urbanisation, migration and economic and social activities on the climate of a particular region. “The fact is Kerala has experienced a drastic transition from a rural entity to a ‘rurban’ entity within a short span of time. This transition has had its impact on the micro-climate of a particular region as well. In this study, we will map how Thiruvananthapuram, Kochi and Kozhikode cities have grown in the past 25 years,” said the scientist. According to George Chackacherry, director, ICCS, during this two-year study, the change in micro-climate will be measured through a time series analysis of effects on permanent vegetation, ambient temperature and rainfall amounts of these cities in the past 25 years.
It has been learned to derive time series urban heat index in the urban and urban sprawl areas of Thiruvananthapuram, Kochi and Kozhikode cities, the trend analysis of temperature and rainfall data from 1950s, 1970s, 1990s and 2010s of these cities will also be examined.After the completion of the study, suggestions including promotion of green belts in urban spaces to contain UHI are likely to be pitched before the policy makers.