Mumbai faces extreme heat conditions due to global warming and urbanization

Mumbai: Increasing global warming and urbanization have led Mumbai to experience extreme heat conditions over the past few decades. Temperatures are expected to rise and affect the health and productivity of residents and the city. The number of “extremely cautious” days when the temperature is between 32°C and 41°C has increased in recent decades, and the number of “cautionary” days when the temperature is between 26°C and 32 °C has increased. decreased, according to Mumbai Climate Action Planof the vulnerability assessment report. According to the report, in 2020, any given day is likely to be classified as extreme caution compared to 1973, especially in the period between March and May and October and November. There have been 12 heat waves between 1973 and 2020, seven of which have occurred in the past 15 years.

These trends likely go hand in hand with global warming. The number of days above 35°C could increase by 20 to 30 days per year by the end of the century and up to 40 days under more extreme emissions and warming scenarios according to the Group’s projections. Intergovernmental Panel on Climate Change (IPCC) reported The era of India.

Wet bulb temperatures should also increase, the wet bulb temperature is a measurement that adds the effect of humidity to heat. Chandni Singh, IPCC author and senior researcher at Indian Institute of Human Settlements said that by 2050, Indian cities are projected to experience wet bulb temperatures of 32°C to 34°C due to high emissions scenarios. The upper limit of human tolerance is considered the wet bulb temperature of 35°C.

Sahil Kanekarsenior program associate with the urban team of World Resources Institute, India which developed the climate analysis and plan for Mumbai said urban development also plays a crucial role in local temperatures. Their analysis revealed that since the construction of the Andheri-Ghatkopar metro, temperatures in Saki Naka increased by about 5°C. The increase in dark, heat-absorbing surfaces such as concrete and asphalt, the reduction in green cover, and the increase in human activities emitting carbon dioxide have led to the “urban heat island effect” .

Temperatures are nearly 6°C to 8°C higher in areas with dense informal settlements and low vegetation than in neighboring areas. Slums absorb and reflect more heat because there is less greenery and use metal and asbestos roofs. According to a report, 40% of people living in a large slum in the M-East district are exposed to temperatures as high as over 35°C, compared to 0.9% of the population in the A district.

Kanekar further said that there should be priority action for neighborhoods such as M-Est where basic infrastructure such as clean water, toilets and accessible open spaces are lacking and inadequate to cope. rising heat. Districts B, C and G (north) also have very low green coverage.

Increasing green coverage, setting up warning systems and cooling centers in vulnerable areas, adopting new building design policies are among the many measures the climate plan proposes to tackle rising heat. The climate plan recommends that by 2030 the plant cover and the permeable surface should be increased by 30 to 40%. And, an increase in open space per capita from 1.8 square meters to 6 square meters by 2040 on an equitable basis.

Mumbai is experimenting with the Miyawaki method of greening. The method is to grow dense thickets very quickly. The climate plan warned against overuse of the method. Kanekar said accessible green spaces are necessary, the forests of Miyawaki are so thick that you cannot enter them.

Teresa H. Sadler