A look at the minimum temperatures across Delhi-NCR reveals a wide variation. Today for instance, if we look at some of the areas located in the periphery of Delhi, we see the following minimum temperatures:
- Akshardham 9.3°C
- Hindon 9.0°C
- Meerut 9.0°C
- Jafarpur 8.9°C
- Jhajjar 8.7°C
- Narela 8.5°C
- Gurgaon 7.4°C
It is to be noted that all the above temperatures are below 10°C. Now if we see the minimum temperatures in the interiors of Delhi we see a completely different story with minimums well over 10°C.
- Indirapuram 13.8°C
- Pitampura 13.4°C
- Delhi university 13.1°C
This variation in minimum temperatures across Delhi-NCR is due to a phenomenon called Urban Heat Island (UHI). UHI is an urban area which is comparatively warmer than its neighboring rural areas. This is mainly due to the human activity known as urbanization. This temperature variation is usually higher at night than during the day, and also when the winds are weak.
UHI is most noticeable during summer and winter seasons. The main reason for this is the modification of land surface for construction work of buildings. The materials used for construction store heat and release it during the night. As population grows so will the number of buildings and thereby, increasing the average temperature.
There is another term known as Heat Island which is less used. Heat Island is referred to an area, irrespective of its population count, which is consistently warmer than its surrounding area.
There is also a stark difference between the two airports in Delhi. Palam recorded minimum temperature of 10.8°C, while Sufdarjung recorded a minimum temperature of 8.8°C on Saturday morning. This difference is due to the fact that in Palam airport there is more air traffic releasing more engine heat. Also, in Palam airport there is more concrete area, due to which temperature is generally higher.
