The National Capital Territory of Delhi is witnessing a strange weather trend this summer – changing temperatures at various places in the city that are less than 5 km away from each other. This event is known as ‘Hit Island’.
For instance, Yamuna Sports Complex recorded a maximum temperature of 46.4 degrees on Saturday, while Mayur Vihar, which is just 10 km from this point, recorded a maximum temperature of 42.8 degrees on the same day. According to meteorologist RK Jenamani, the situation in Delhi is known as ‘Hit Island Effect’.
What is the Hit Island Effect?
According to the US Environmental Protection Agency website, urban centers, mostly man-made structures such as buildings, malls, metro-stations – become ‘islands’ of higher temperatures than on the outskirts of cities.
This is because buildings, roads and other man-made infrastructure absorb more of the sun’s heat and emit it back in larger amounts, hence causing more hearing. Whereas the situation is opposite when it comes to areas having natural resources like water bodies and green cover.
This process is called the “hit island effect”.
According to Genamani, the “hit island effect” causes a temperature increase of up to 8 degrees. As a result, the temperature changes even at a distance of less than 300 meters.
For example, if a person measures the temperature in the Lodhi Garden area – which is surrounded by greenery – he will find the temperature to be 6-8 degrees lower than the maximum temperature of the city.
This is the reason why the temperature measured in Akshardham is higher than the temperature in other parts of the city. According to Janamani, there is no greenery around Akshardham. And that is why, being in the vicinity of river Yamuna also does not help in controlling the temperature in Akshardham.
While there is Sanjay Lake in Mayur Vihar and this area is surrounded by greenery.
Sanjay Lake is an artificial lake developed by DDA, which connects to Mayur Vihar area.
India is facing severe heat this year. According to IMD, this year has been the hottest ever. The temperature in the north-west regions of the country is rising up to 46 degree Celsius.