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Urban Heat Island (UHI) Effect

PYQs

7

Articles

1

Momentum

19

Phase IFoundation

Background

Overview

Essential for understanding urban climate, sustainable urban planning, climate change adaptation strategies, and public health in cities. Relevant for GS1 (Urbanization, Geography), GS3 (Environment).

The Urban Heat Island (UHI) effect is a phenomenon where urban areas experience significantly higher temperatures than surrounding rural areas due to human activities and altered land surfaces. It is a key factor in intensifying heat stress in densely populated regions.

Phase IIStatic core

Facts & tables

Key facts

Temperature Difference

Urban areas can be 4 to 5 degrees Celsius warmer than nearby open areas, contributing to discomfort and 'real-feel' temperatures.

Causes

Primarily caused by land use and land cover changes, such as the replacement of natural vegetation with heat-absorbing concrete and asphalt.

Nighttime Heat

Concrete structures absorb and slowly release heat throughout the day, leading to persistently elevated nighttime temperatures indoors.

Aggravating Factors

Denser population and traffic further add to the UHI effect in urban environments.

Reference table

Static syllabus anchors

TypeReference
Conceptual areaClimate Change Adaptation
Conceptual areaUrban Planning
Phase IIIExam lens

Prelims angle

Overview

Prelims angle: Statement-based questions

Prelims angle: Conceptual understanding

Quick revision

  • Urban areas significantly warmer than rural counterparts.
  • Caused by land use changes (concrete, asphalt).
  • Leads to higher indoor and nighttime temperatures.
  • Mitigation: urban greening, cool roofs, sustainable construction.
  • Exacerbates heat stress in cities.

High-confidence PYQs

2026Multi-statement analysis, Factual recall

With reference to the climate of Andaman and Nicobar Islands, which of the following statements is/are correct ? 1. The climate can be defined as a humid, t...

GeographyOpen question
2025Multi-statement analysis, Conceptual understanding

Consider the following statements: Statement I: In January, in the Northern Hemisphere, the isotherms bend equatorward while crossing the landmasses, and po...

GeographyOpen question
2024Factual recall, Conceptual understanding

One of the following regions has the world's largest tropical peatland, which holds about three years worth of global carbon emissions from fossil fuels; and...

Environment & EcologyOpen question
2023Statement-based questions, Conceptual understanding

Consider the following statements : Statement-I: The temperature contrast between continents and oceans is greater during summer than in winter. Statement...

GeographyOpen question
2021Statement-based questions, Conceptual understanding

Consider the following statements: 1. In the tropical zone, the western sections of the oceans are warmer than the eastern sections owing to the influence of...

GeographyOpen question
2020Statement-based questions, Conceptual understanding

With reference to Ocean Mean Temperature (OMT), which of the following statements is/are correct? 1. OMT is measured up to a depth of 26°C isotherm which is...

GeographyOpen question
2013Multi-statement analysis, Conceptual understanding

The annual range of temperature in the interior of the continents is high as compared to coastal areas. What is/are the reason/reasons? 1. Thermal difference...

GeographyOpen question

Topic timeline

Climate Change AdaptationUrban Planning
Prelims 2013· Multi-statement analysis, Conceptual understanding

The annual range of temperature in the interior of the continents is high as compared to coastal areas. What is/are the reason/reasons? 1. Thermal difference...

Open question
Prelims 2020· Statement-based questions, Conceptual understanding

With reference to Ocean Mean Temperature (OMT), which of the following statements is/are correct? 1. OMT is measured up to a depth of 26°C isotherm which is...

Open question
Prelims 2021· Statement-based questions, Conceptual understanding

Consider the following statements: 1. In the tropical zone, the western sections of the oceans are warmer than the eastern sections owing to the influence of...

Open question
Prelims 2023· Statement-based questions, Conceptual understanding

Consider the following statements : Statement-I: The temperature contrast between continents and oceans is greater during summer than in winter. Statement...

Open question
Prelims 2024· Factual recall, Conceptual understanding

One of the following regions has the world's largest tropical peatland, which holds about three years worth of global carbon emissions from fossil fuels; and...

Open question
Prelims 2025· Multi-statement analysis, Conceptual understanding

Consider the following statements: Statement I: In January, in the Northern Hemisphere, the isotherms bend equatorward while crossing the landmasses, and po...

Open question
Prelims 2026· Multi-statement analysis, Factual recall

With reference to the climate of Andaman and Nicobar Islands, which of the following statements is/are correct ? 1. The climate can be defined as a humid, t...

Open question

Beyond high temperatures: understanding heat stress in Tamil Nadu

14 Jun 2026 · UHI effect causes urban areas to be hotter than rural surroundings due to built environments and human activities. It exacerbates heat stress, particularly at night, and necessitates urban greening and sustainable construction for mitigation.

Read article

Related topics

Current topic

Urban Heat Island (UHI) Effect

Often confused with

Heat Stress and Heatwaves

Open notes

Practice writing on this topic

UPSC has asked 7 linked questions on Urban Heat Island (UHI) Effect in Mains. Write an answer to one — and get it evaluated.

See Mains PYQsEvaluate an answer
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