Urban Heat Island Effect
Geography
- PYQs8
- Articles2
Background
Crucial for understanding urban planning challenges, sustainable development, climate change adaptation in cities, public health, and environmental management in rapidly urbanizing India.
The Urban Heat Island (UHI) effect describes the phenomenon where urban areas experience significantly higher temperatures than surrounding rural areas, primarily due to human activities, dense construction, and the prevalence of heat-absorbing surfaces like concrete and asphalt.
Facts & tables
- Causes
- Dense building structures, dark impervious surfaces (roads, roofs), reduced vegetation cover, and anthropogenic heat generation from vehicles and industries.
- Impacts
- Exacerbates heat stress during heatwaves, increases energy consumption for cooling, and can worsen air quality.
- Manifestation
- Hyderabad, despite not always recording the highest regional temperatures, is identified as having a 'strong urban heat island' effect.
- Mitigation
- Strategies include increasing green spaces, using cool roofs and pavements, and implementing sustainable urban planning.
- Temperature Differential
- Urban areas can be 2°C to 10°C hotter than surrounding rural areas.
- Consequences
- Contributes to increased energy consumption for cooling and worsened air quality.
- Exacerbation
- Exacerbates the impact of global warming in urban settings.
| Type | Reference |
|---|---|
| Conceptual area | Urban Planning |
| Conceptual area | Climate Change Adaptation |
| Conceptual area | Environmental Geography |
Prelims angle
Prelims angle: Statement-based questions
Prelims angle: Conceptual understanding
- Urban areas are warmer than surrounding rural areas.
- Caused by concrete, asphalt, lack of green cover, anthropogenic heat.
- Increases heat stress and energy demand in cities.
- Mitigation involves green infrastructure, cool surfaces.
- A key challenge in urban climate resilience.
| Year | Framing tags |
|---|---|
| 2025 | Multi-statement analysis, Conceptual understanding |
| 2025 | Statement-based questions, Conceptual understanding |
| 2024 | Multi-statement analysis, Conceptual understanding |
| 2023 | Statement-based questions, Conceptual understanding |
| 2021 | Statement-based questions, Conceptual understanding |
| 2020 | Statement-based questions, Conceptual understanding |
| 2019 | Factual recall, Multi-statement analysis |
| 2013 | Multi-statement analysis, Conceptual understanding |
Timeline
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Urban Planning
Conceptual area
-
Climate Change Adaptation
Conceptual area
-
Environmental Geography
Conceptual area
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Prelims 2013
Multi-statement analysis, Conceptual understanding
-
Prelims 2019
Factual recall, Multi-statement analysis
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Prelims 2020
Statement-based questions, Conceptual understanding
-
Prelims 2021
Statement-based questions, Conceptual understanding
-
Prelims 2023
Statement-based questions, Conceptual understanding
-
Prelims 2024
Multi-statement analysis, Conceptual understanding
-
Prelims 2025
Multi-statement analysis, Conceptual understanding
-
Prelims 2025
Statement-based questions, Conceptual understanding
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A heat crisis in Telangana that burns beyond the thermometer
The Urban Heat Island effect makes cities significantly hotter than rural areas due to urban infrastructure, intensifying heat stress and requiring specific mitigation in urban planning.
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Concrete fever: On India and heat management
The Urban Heat Island effect causes cities to be significantly hotter than rural areas due to urban infrastructure and activities, intensifying heat stress and demanding climate-resilient urban design.
See also
Past papers
2013–2025 · 8 questions
In the news
Concrete fever: On India and heat management
The Urban Heat Island effect causes cities to be significantly hotter than rural areas due to urban infrastructure and activities, intensifying heat stress and demanding climate-resilient urban design.
A heat crisis in Telangana that burns beyond the thermometer
The Urban Heat Island effect makes cities significantly hotter than rural areas due to urban infrastructure, intensifying heat stress and requiring specific mitigation in urban planning.
Try these PYQs
Consider the following statements :
Statement-I: The temperature contrast between continents and oceans is greater during summer than in winter.
Statement-II: The specific heat of water is more than that of land surface.
Which one of the following is correct in respect of the above statements?
Statement-I is incorrect: The temperature contrast between land and ocean is actually greater in winter, not in summer. In winter, land loses heat quickly and becomes much colder, while the ocean retains heat and stays relatively warm → large contrast.
In summer, both land and ocean warm up, but the difference is less pronounced compared to winter → smaller contrast. Statement-II is correct: Water has a higher specific heat capacity than land. It heats up and cools down more slowly, which explains why oceans have a moderating influence on temperature.
Consider the following statements:
Statement I:
In January, in the Northern Hemisphere, the isotherms bend equatorward while crossing the landmasses, and poleward while crossing the oceans.
Statement II:
In January, the air over the oceans is warmer than that over the landmasses in the Northern Hemisphere.
Which one of the following is correct in respect of the above statements?
✅ Statement I: Correct
In January, isotherms bend equatorward over land (which cools faster) and poleward over oceans (which retain heat). ✅ Statement II: Correct
Oceans stay warmer than land in January because water has a higher specific heat. ✅ Relationship:
Statement II explains why the isotherms behave as described in Statement I. Correct Answer: Both statements are correct, and Statement II explains Statement I.
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 trade winds.
2. In the temperate zone, westerlies make the eastern sections of oceans warmer than the western sections.
Which of the statements given above is/are correct?
Statement 1 is correct. The trade winds in the tropical zone blow from east to west, causing the western sections of the oceans to be warmer than the eastern sections. This is because these winds push the warm surface waters towards the west. Statement 2 is correct. On the other hand, in the temperate zone, the westerlies blow from west to east. These winds push the warm waters towards the eastern sections of the oceans, making them warmer than the western sections. Therefore, both statements are correct.
Consider the following statements:
I. Without the atmosphere, temperature would be well below freezing point everywhere on the Earth's surface.
II. Heat absorbed and trapped by the atmosphere maintains our planet's average temperature.
III. Atmosphere's gases, like carbon dioxide, are particularly good at absorbing and trapping radiation.
Which of the statements given above are correct?
Statement I is correct: Without the atmosphere to trap heat, the Earth’s surface temperature would drop to well below freezing, making it too cold to support life as we know it.
In statement 1 though it's an extreme statement but from UPSC CSE point of view it's generally considered true. Statement II is correct: The atmosphere absorbs and retains heat (a natural greenhouse effect), which helps maintain the Earth’s average temperature within a habitable range. Statement III is correct: Gases such as carbon dioxide, methane, and water vapor are particularly effective at absorbing and trapping infrared radiation, helping to warm the planet.
Consider the following states:
1. Chhattisgarh
2. Madhya Pradesh
3. Maharashtra
4. Odisha
With reference to the States mentioned above, in terms of percentage of forest cover to the total area of State, which one of the following is the correct ascending order?
The correct ascending order for the percentage of forest cover in the mentioned states 1. Odisha (32.34%)
2. Madhya Pradesh (25.11%)
3. Maharashtra (16.47%)
4. Chhattisgarh (41.09%) Chhattisgarh has the highest forest cover percentage, followed by Odisha, Madhya Pradesh, and Maharashtra. Hence the correct answer is option 3, i.e 3-2-4-1. (Ascending order)
Show 3 more PYQs
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 between land and water
2. Variation in altitude between continents and oceans
3. Presence of strong winds in the interior
4. Heavy rains in the interior as compared to coasts
Select the correct answer using the codes given below.
The correct answer is 1 only (Thermal difference between land and water). Statement 1 is correct: Land heats up and cools down much faster than water. This is because water has a higher specific heat capacity, meaning it takes more energy to heat it up and more energy to cool it down. Coastal areas, being influenced by large water bodies, experience a moderating effect on temperature fluctuations. The temperature changes are more gradual throughout the year. Statement 2 is incorrect: While altitude can affect temperature (higher altitude generally means cooler temperatures), this is not the primary reason for the difference between continental interiors and coasts. Both continents and oceans have variations in altitude. Statement 3 is incorrect: Winds can play a role in influencing local temperatures, but their presence wouldn't explain the consistent pattern of higher annual ranges seen in continental interiors. Statement 4 is incorrect: Rainfall patterns can affect temperature to some extent, but coastal areas often receive more rainfall compared to continental interiors. This wouldn't explain the higher annual range observed inland.
Consider the following statements:
Statement-I: Thickness of the troposphere at the equator is much greater as compared to poles.
Statement-II: At the equator, heat is transported to great heights by strong convectional currents.
Which one of the following is correct in respect of the above statements?
* Statement-I: Correct - The troposphere is thicker at the equator than at the poles. This is because the equator receives more direct sunlight, leading to warmer temperatures and greater air expansion. This expanded air results in a greater height of the troposphere. * Statement-II: Correct - Convection is a significant mode of heat transfer in the atmosphere. At the equator, intense solar heating causes air to rise rapidly in strong convectional currents. This rising air carries heat to higher altitudes, contributing to the vertical distribution of heat in the troposphere. * Statement II directly explains Statement I. The strong convectional currents mentioned in Statement II are the primary reason for the greater thickness of the troposphere at the equator, as explained in Statement I. The rising air due to convection leads to the expansion and increased height of the troposphere in equatorial regions.
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 129 meters in the south-western Indian Ocean during January-March.
2. OMT collected during January-March can be used in assessing whether the amount of rainfall in monsoon will be less or more than a certain long-term mean.
Select the correct answer using the code given below:
Statement 1 is incorrect. OMT is measured up to the depth of the 26°C isotherm, but the 129-meter depth mentioned in the southwestern Indian Ocean during January-March is incorrect. The depth of the 26°C isotherm can vary depending on the region and season. Statement 2 is correct. OMT collected during January-March helps in predicting the amount of rainfall during the monsoon. It is used to assess whether rainfall will be more or less than the long-term average, as variations in OMT influence monsoon behaviour. Hence, option B is the correct answer.