Figure 1: No Copyright Infringement Intended

Context:

• Mumbai lost 81% of its open land (barren spaces without any vegetation), 40% green cover (forests & scrublands) and approximately 30% of its water bodies (lakes, ponds, floodplains) between 1991 and 2018, while the built-up area (areas developed upon) rose by 66% in the same period.
• It concludes that the city witnessed a 2-degree Celsius average temperature rise across 27 years.
• with this pace of urbanisation and landscape transformation, it is expected that the Urban Heat Island intensity will further increase in the city.

About  Heat Island:

• Heat islands are urbanized areas that experience higher temperatures than outlying areas.
• Structures such as buildings, roads, and other infrastructure absorb and re-emit the sun’s heat more than natural landscapes such as forests and water bodies.
• Urban areas, where these structures are highly concentrated and greenery is limited, become “islands” of higher temperatures relative to outlying areas.
• Daytime temperatures in urban areas are about 1–7°F higher than temperatures in outlying areas and nighttime temperatures are about 2-5°F higher.
• It is the first-ever national database of unorganised workers including migrant workers, construction workers, gig and platform workers, etc.

Impacts of Heat Island:

• Heat islands increase both overall electricity demand, as well as peak energy demand.
• Heat islands contribute to higher daytime temperatures, reduced nighttime cooling, and higher air-pollution levels. These, in turn, contribute to heat-related deaths and heat-related illnesses such as general discomfort, respiratory difficulties, heat cramps, heat exhaustion, and non-fatal heat stroke.
• High temperatures of pavement and rooftop surfaces can heat up stormwater runoff, which drains into storm sewers and raises water temperatures as it is released into streams, rivers, ponds, and lakes. Water temperature affects all aspects of aquatic life, especially the metabolism and reproduction of many aquatic species. 
• Excessive heat is a financial burden for low-income households. F

Concept of Heat Equity:

• Heat equity refers to the development of policies and practices that mitigate heat islands and help people adapt to the impacts of extreme heat in a way that reduces the inequitable distribution of risks across different populations within the same urban area.

Heat island and Climate Change:

• our warming climate will increase already higher temperatures in heat island areas.
• Second, cooling strategies to reduce heat islands can help communities adapt to the impacts of climate change as well as lower the greenhouse gas emissions that cause climate change .