Urban Heat Island Effect in Kolkata
The Urban Heat Island effect is a major environmental problem in Kolkata. In recent years, the temperature in Kolkata has been increasing rapidly due to rapid urbanization, concrete construction and reduction of green areas. More and more residential apartments are taking the places of old joint families with large area and trees, people now want to stay alone and free without their relatives, so number of small family increased and space becomes short for nature.
Urban Heat Island means that the city area becomes significantly hotter than nearby rural areas due to human activities and infrastructure. It is nearly impossible for human being to withstand that unbearable heat.
Why Kolkata Is Getting Hotter Every Year
1. Excessive Concrete Buildings
Concrete, asphalt and brick absorb heat during the day and release heat slowly at night. This makes the city remain hot even after sunset.
2. Reduction of Trees and Water Bodies
Kolkata and surrounding areas once had many wetlands, ponds and trees. These natural elements helped cool the environment. Urban development has reduced these cooling elements.
3. Air Conditioners and Vehicles
Air conditioners throw hot air outside buildings and vehicles produce heat and pollution. These increase the surrounding temperature of the city.
4. High Population Density and increasing separate leaving
More buildings, more roads and more human activities generate more heat as people now ditching joint families and staying alone, which increases the overall city temperature, demands more space per capita and less space for large trees.
5. Materialistic greed of a developing nation
People are running behind better livelihood, suffering from inferiority complex. Forgetting their roots and nature, destroying the culture, heritage to adopt some imaginary better life.
Effects of Urban Heat Island in Kolkata
Higher Electricity Consumption
As temperature increases, people use more fans and air conditioners, increasing electricity consumption.
Health Problems
Extreme heat can cause dehydration, heat stroke and breathing problems, especially for elderly people and children.
Water Shortage
Higher temperatures increase water evaporation and create water shortage problems.
Increasing anger and depreciated mental health
Human nerve system does not like higher temparature and it panicked with anger and negative behaviour
Revenue loss
Foreign tourists, domestic travellers avoid the summer season to visit city areas during extreme heat connditon and poor AQI as air quality is directly related to number of trees and heat island effect.
How to Reduce Urban Heat Island Effect
Waterbody protection and creating new waterbodies
Existing waterbodies need to be protected and we need much more waterbodies as water cool any warm thing including the mother earth
Destroy concrete and Roadside tree plantation
Large scale roadside tree plantation is atmost necessary now to increase canopy area scientifically.
Rooftop Gardens
Rooftop gardens reduce roof temperature and help cool buildings naturally.
Vertical Gardens
Vertical gardens on walls reduce wall temperature and absorb heat from sunlight.
Planting Trees
Trees provide shade and release moisture into the air, which helps reduce surrounding temperature. In kolkata, tree canopy cover has been decreased to less than 3% which is extremely bad, if tree canopy cover can be increased upto 20% of the total area, 4-5 degree C temparature can be reduced thereby extreme summer temparature of 40C can be reduced to 36C.
Use of Cool Roof Materials
White or reflective roof materials reflect sunlight and reduce heat absorption.
Creating Pocket Miyawaki forests
Beside Roadside plantation to increase canopy coverage across the city, pocket miyawaki forests needs to be created across empty lands and parks.
Natural Cooling Is the Future
To make Kolkata sustainable and livable, natural cooling methods, such as rooftop gardening balcony gardens, water bodies and urban tree plantation are very important.
If cities continue to grow without environmental planning, the Urban Heat Island effect will continue to increase in the future.