New Delhi: Mumbai has recorded significant increases in nighttime temperatures amidst India’s ongoing severe heatwave, according to a recent analysis released on Friday. The study reveals that climate change has augmented the number of nights where temperatures exceed 25 degrees Celsius by approximately 50 to 80 nights annually, adversely impacting sleep patterns and public health.
The report, conducted by Climate Central and Climate Trends, underscores that global warming has led to a notable escalation in nighttime temperatures, surpassing even daytime temperature rises. This trend is primarily attributed to the escalating use of fossil fuels such as coal, oil, and gas.
India, identified as one of the countries most vulnerable to climate change impacts, has witnessed a pronounced elevation in minimum nighttime temperatures over the past decade. The India Meteorological Department reported that New Delhi recently experienced its warmest night in at least 12 years, with temperatures reaching 35.2 degrees Celsius—the highest since 1969.
The analysis further highlights that between 2018 and 2023, numerous cities across Kerala, Karnataka, Maharashtra, Tamil Nadu, Punjab, Jammu and Kashmir, and Andhra Pradesh observed between 50 to 80 additional nights per year above the 25 degrees threshold due to climate change. Mumbai, among the major metropolitan areas, has seen the most substantial increase in nighttime temperatures, with an additional 65 days of warmer nights attributed to global warming.
West Bengal and Assam have been particularly affected, with cities like Jalpaiguri, Guwahati, Silchar, Dibrugarh, and Siliguri experiencing an average of 80 to 86 additional nights annually above 25 degrees due to climate change impacts.
Various other cities, including Jaipur, have also reported between 15 to 50 additional nights where minimum temperatures exceeded 25 degrees, underscoring the pervasive influence of climate change.
The rising nighttime temperatures pose significant health risks, impairing physiological comfort and exacerbating mortality rates, particularly among vulnerable demographics such as the elderly and those lacking adequate cooling resources.
These findings coincide with recent records of nighttime heat across several Indian cities. Delhi, for instance, set a new record on June 19 with temperatures reaching 35.2 degrees overnight. Similarly, Alwar in Rajasthan recorded its highest-ever nighttime temperature of 37 degrees, marking a considerable increase in nights above 25 degrees attributed to climate change.
Scientific studies by World Weather Attribution and ClimaMeter confirm that climate change has intensified India’s current heatwave, making it hotter, more frequent, and increasingly likely.
Roxy Mathew Koll, a Climate Scientist at the Indian Institute of Tropical Meteorology in Pune, emphasized the urban heat island effect, noting that cities become several degrees warmer than surrounding rural areas due to heat absorption and re-emission from buildings and infrastructure.
Aarti Khosla, Director of Climate Trends, warned of escalating nighttime temperatures exacerbating sleeplessness and health impacts, particularly in urban areas vulnerable to the urban heat island effect. She urged immediate action to mitigate these trends, cautioning that without substantial reductions in fossil fuel consumption, nighttime temperatures may not fall below 25 degrees in some areas by the end of the century.
In conclusion, the analysis underscores the urgent need for proactive measures to mitigate the escalating impacts of nighttime warming driven by climate change, ensuring sustainable urban planning and resource management to safeguard public health and well-being.
