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By: Aveek Ghosh
Assistant Professor, Department of Architecture, Nitte Institute of Architecture, Panner Campus, Kotekar Beeri Road, Deralakatte, Mangaluru, Karnataka, India
Heat waves (HWs) or extreme heat events (EHEs), aggravated by the global temperature rise, present unprecedented challenges to both human health and urban infrastructure. Recently, regions in India have been suffering from unbearable conditions due to humid heat events. Coastal states like Odisha, Andhra Pradesh, Maharashtra, and Gangetic West Bengal have faced extreme heat, coupled with high humidity levels. Current strategies for managing extreme heat mainly focus on resilience to dry heat based on temperature alone, neglecting the complex nature of heat extremes. Factors, such as humidity and wind speed are key in assessing the true impact of heat on both ecosystems and human health. This article highlights the importance of measuring humid heat extremes using indicators that factor in humidity, such as wet-bulb globe temperature and the Universal Thermal Climate Index. It stresses the significant role of humidity in shaping heat extremes and calls for further exploration of these effects in a warming climate. The paper urges the swift development of strategies to combat the rising threats of heat and humidity, particularly in Indian cities facing rapid urbanization and climate change. Future heat action plans should incorporate comprehensive biometeorological metrics, considering humidity as an essential factor in evaluating heat-related health risks. The study advocates for creating integrated heat-health warning systems involving experts from fields, such as epidemiology, biometeorology, public health, urban planning and climate science.
Keywords: Humid heat, biometeorological metrics, India, heat-health warning systems, urban heat resilience.
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