Pre-monsoon Delhi temperatures higher than usual in 3 yrs, RS told
THE AVERAGE PREMONSOON (MARCH, APRIL AND MAY) MAXIMUM TEMPERATURE WAS 34.4 DEGREES CELSIUS (°C) IN 2020
Maximum and minimum temperatures in Delhi during the pre-monsoon months have increased over the last three years, even though the relative humidity displayed no such trend, Union minister for science and technology Jitendra Singh said in Rajya Sabha on Thursday, attributing this to urbanisation, the lack of rain and absence of western disturbances.
The average pre-monsoon (March, April and May) maximum temperature was 34.4 degrees Celsius (° C) in 2020, 36°C in 2021and 37.9°C in 2022, data presented before the House showed.
The pre-monsoon minimum temperatures were 20.7°C in 2020, 21.35° C in 2021 and 21.96°C in 2022.
However, the relative humidity ( RH) dropped this year.
The RH recorded at 3am UTC ( coordinated universal time) was 68.4% in 2020, 61.4% in 2021 and 60% in 2022, the data showed, while the RH at 12pm UTC was 43.5% in 2020, 37% in 2021 and 31% in 2022.
“Several studies have been carried out on the pre- monsoon temperature pattern of Delhi and the likely causes. Urbanisation is one of the main causes that can influence the changes in temperature patterns within the city and form heat islands. This is reflected by the trends of difference in annual mean minimum temperature of the two stations of which one ( Safdarjung) is within the city and the other is in the outer periphery in Delhi NCR (Palam),” Singh said.
He added, “A recent article published in Nature, describes the reason for India’s prolonged spell of heat wave experienced during pre-monsoon season 2022. The causes were mentioned as the absence of rainfall and convective activities for a long period, the absence of western disturbances and the subsidence of warm and dry air in lower and middle tropospheric levels over the North Arabian Sea and adjoining South Pakistan and Gujarat.”
Environment experts said rising temperatures during the pre-monsoon months in Delhi have been a trend for the last few years. This trend could be attributed to the larger role of the climate crisis, they said.
“This is an impact of the climate crisis, which is leading to higher temperatures being recorded in the months of March, April and June. The pre-monsoon activities are also becoming less this season, which means that we are not getting enough rain in this period that can provide relief from these temperatures,” said Mahesh Palawat, vice- president, Skymet Weather.