As a heatwave continues to sweep across the nation, Bangladesh is being gripped by oppressively high temperatures. While residents of Dhaka eagerly await rain relief from the heat at the start of summer, the mercury has continued to shatter records.
Jashore and Chuadanga recorded the highest temperature, 41.8 degrees Celsius, while it was 40.5 degrees Celsius in Dhaka, which is the highest in the capital in 58 years, on Sunday.
On Saturday, the highest temperature was recorded in Chuadanga, 42.2 degrees Celsius, while it was 40.4 degrees Celsius in Dhaka.
An intense heatwave was sweeping over Dhaka, Faridpur, Manikganj, Pabna, Bagerhat, Jashore, Chuadanga and Kushtia. Other regions of the country were experiencing a mild to moderate heatwave, said Kazi Zabunnessa, an assistant meteorologist at the Met Office.
“The heatwave might continue for two-three more days. Day temperatures might stay unchanged but might rise at night.”
The country has not experienced even drizzles since Apr 4 with the last rain in Dhaka occurring on Apr 2. Light rains occurred in Sylhet and some other regions outside Dhaka on Apr 4 last.
“A lack of rainfall has caused the temperatures to soar. There is a possibility of rain at the end of the week.”
Meteorologists consider the 36-38 degrees Celsius threshold as a mild heatwave and 38-40 degrees Celsius as a moderate heatwave. Temperatures beyond 40 degrees Celsius are categorised as severe heatwaves.
The highest temperature on record for Dhaka was 42.3 degrees Celsius in 1960. In 1995 and 2002, the country recorded a highest temperature of 43 degrees Celsisus. That was after Rajshahi recorded 45.1 degree Celsius in May 1972.
THE WAIT FOR RAIN
Meteorologist Abul Kalam Mallick said there was a slight possibility of rain three days later at Rangpur and Rajshahi divisions along with some other regions of the country. The likelihood of rains occurring will increase in the next week, he added.
Despite the severe temperatures, less humidity kept it tolerable. The temperatures might fall over the next few days while humidity rises, Mallick said.
“It will cause sweating. So it will feel more unpleasant despite lower temperatures.”
The forecast for the month of April already signalled that along with heatwaves, moderate to heavy rainfall in the northeastern part of the country might trigger flash floods towards the end of the month.
REASON BEHIND INTENSE HEATWAVE
Dr Samarendra Karmakar, a former director of the Met Office, said temperatures were usually such in April-May and sometimes even higher, though the intensity might vary.
“The kind of heatwave that is blowing over the country in April has raised fears that it might be even more severe in May. The mercury rose to 43.4 degrees Celsius in Satkhira in May 2002.”
He also mentioned that in recent years, unrelenting heatwave swept over the country in 2014 and 2019 as well.
“This often happens. These areas [Satkhira, Jashore, Kushtia, Rajshahi] experienced very intense heatwaves in those periods. There was a drought in 1979 as the rainy seasons emerged late. There were times when the monsoon arrived in the second week of June, though it was supposed to emerge in the first week.”
“Chuadanga is situated just below Satkhira, which recorded the highest temperature two decades ago. But in recent year, the mercury rose to 42 degrees Celsius there and nearby areas, but not past that. Heatwave occur in Jashore, Kushtia, Rajshahi, Satkhira, Chuadanga and some areas of Khulna. But Sreemangal joins these places during cold snaps.”
On Saturday, Jahore recorded 40.8 degrees Celsius, Khulna 39.7 degrees Celsius, Rajshahi 39.5 degrees Celsius, Ishwardi 41.2 degrees Celsius, Mongla 40 degrees Celsius, Kumarkhali 40.8 degrees Celsius and Faridpur 41.3 degrees Celsius.
“This means Satkhira, Jashore, Kushtia and Rajshahi are where out heatwaves and coldwaves occur. The coldwaves in winter enter the country from the same place heatwaves blow into the country, from the west-northwestern part,” said Samarendra, a former chairman of National Oceanographic and Maritime Institute.
“Analysis reveals that some areas in Bihar, West Bengal, Bangladesh and adjacent Odisha are completely empty. With no clouds there, the heat energy from sunbeams is trapped in these areas.”
“The clouds that float in from the west or northwest disappear at western Bihar and Odisha. A tropical high pressure zone is active over West Bengal, Bihar and Bangladesh. The moisture from the Bay of Bengal cannot be carried over there. Low pressure needed for rain does not occur in Bihar and West Bengal regions.”
Samarendra said heatwave might continue for 2-4 more days and once the rain and storms begin, they might continue for some days as well.”
Samarendra stressed that unplanned urbanisation was a key reason for the growing heatwave.
Source: bdnews24
