Karachi endures ‘hottest’ period after 2015 heatwave

- Met official says city’s monthly average temperature remained 4 degrees Celsius higher than average during the ongoing heatwave - High levels of humidity make weather ‘very difficult to bear’ - With 39.2°C on Sunday, feels-like temperature surges to 55°C at 5pm

KARACHI: The city remained in the grip of sweltering weather conditions for the eighth consecutive day on Sunday on account of continued disruption of the sea breeze caused by a low atmospheric pressure area prevailing over southeast of Karachi.

Chief Meteorologist Dr Sardar Safaraz told Dawn that the current weather conditions were the hottest since the 2015 heatwave during which the maximum temperature surged to 44.8°C.

“We are seeing a repeat of similar weather conditions after nine years. The deviation from monthly average temperature remained around or above four degrees Celsius in Karachi during the ongoing heatwave,” he said when asked about the intensity of the ongoing heatwave.

He said that this year the maximum temperature recorded was 42°C.

Dr Sarfaraz pointed out that in both cases of heatwaves experienced in 2015 and 2024, harsh weather conditions were caused by a low atmospheric pressure area.

“What’s specific to Karachi is high levels of humidity that makes hot weather very difficult to bear as it increases the feels-like temperature manifold. This week, humidity has remained 50 per cent or above 50pc,” he added.

He said that the minimum temperature of the month of June this year had also remained high i.e. on an average of 29-30°C.

The ever-highest temperature of the month of June in Karachi was 47°C, recorded on June 18 1979. The highest temperature of the month of May was 48°C, which was recorded on May 9, 1938.

“Weather patterns have changed due to the warming world. Studies suggest that intense weathers would become more frequent, prolonged and violent as global temperature rises,” Dr Sarfaraz said while referring to a study by World Weather Attribution that has linked the 2022 devastating floods in Pakistan to climate change.

‘Tenfold increase in Karachi’s mean temperature’

Senior teacher and researcher at Karachi University’s Institute of Environmental Studies Dr Aamir Alamgir said that Karachi’s yearly average temperature is 25.9°C and the average annual precipitation is roughly 194 millimetres.

“Over the [past] 59 years, an increase of 2.25°C in mean temperature has been recorded. That’s an increase of 0.38°C per decade, which is tenfold the global increase in temperature,” he said.

“Humidity in Karachi varies from 58pc in December, the driest month, to 85pc in August, the wettest month. During the 2015 heatwave, the heat index reached 66°C,” he added.

“Combined with damaged water supply networks, frequent power outages and blackouts, the consequences for those in Karachi’s lower socioeconomic strata were catastrophic. Unfortunately, several precious lives are lost this year as well during the heatwave,” he said.

Three die from heatstroke

On Sunday, officials said that three persons died from heatstroke in the Abbasi Shaheed Hospital and Jinnah Postgraduate Medical Centre.

The Met department’s data showed that humidity was 63pc at 10:00am when the temperature was 35°C, raising the heat index to 47°C.

The heat index increased to 55°C at around 5:00pm as the temperature rose to 39.2°C with 54pc relative humidity.

The maximum temperature recorded in the city on Saturday was 38°C.

“The low-pressure area has weakened over the past two days but is still there. We are expecting that it will completely lose its influence over Karachi by tomorrow morning and the heatwave conditions will subside,” said Dr Sarfraz.

Published in Dawn, July 1st, 2024