Editor Mr.Mayank Rawat ( Chief Editor Mr. Rohit Mishra )
New Delhi: Pitampura and the Ridge in north Delhi have recorded higher temperatures than Safdarjung, the city’s base station, on most days this season. Experts say that some parts of Delhi are hotter than others because of the heat island effect, inadequate green cover, and other factors.
On April 3, the maximum temperature at the weather station on Delhi’s Northern Ridge rose to 40.4 degrees Celsius, six degrees higher than the season’s normal. At Safdarjung, about 15 km from the Ridge, the day temperature was 39 degrees Celsius. Some parts of Delhi saw a lower temperatures than Safdarjung. The maximum was 35.8 degrees at Mayur Vihar. The stations at Pusa recorded 36.4 and at Rajghat 36.6 degrees Celsius.
Similarly, on March 26, the mercury crossed 40 degrees Celsius at the Ridge and Pitampura. The maximum at Safdarjung was 38.9.
Experts said the heat island effect causes some areas to become warmer than others. IMD said the temperature in urban areas varies from place to place depending on local factors such as proximity to water bodies, presence of barren land, concrete and dense urban clusters, green areas. “Some areas experience a stronger impact from the arid and scorching winds originating in Rajasthan because of their geographical positioning. Their location on Delhi’s western periphery means that the winds reach these places first, before hitting other parts of the city,” a Met official said.
Manju Mohan, former professor at the Centre for Atmospheric Sciences, IIT Delhi, said: “The urban heat island effect is mainly due to anthropogenic activities and land use cover. Anthropogenic heat emissions are from vehicles, other types of fuel burning, air conditioners, gadgets, etc. Land use cover like higher built-up areas and lack of green areas give rise to a higher urban heat effect.”
“During the daytime, there is an urban cool island effect. Because during the day, the solar heat is absorbed by the building making it slightly cooler but during nighttime, this heat which is absorbed by the building causes higher temperature over the urban built-up area in comparison to the neighbouring areas,” she said.
Mohan said local and regional factors like wind direction also contribute to the heating effect. “If there is rainfall under the influence of a western disturbance, it may lead to a cooling effect,” she said.
In summer last year, the western areas of Delhi, such as Mungeshpur, Najafgarh and Jafarpur, recorded a higher number of heatwave days. For instance, Safdarjung recorded five heatwave days in May last year, while Mungeshpur, Najafgarh, and Jafarpur were under the grip of nine to ten heatwave days.
Mayank Rawat
