Indication of major changes in weather patterns

People suffer under the scorching sunFile photo

When a major cyclone hits, temperatures generally dip with heavy rainfall over large areas, including neighbouring countries affected by the cyclone.

But most parts of Bangladesh continued to feel boiling temperature before and after cyclone Mocha made landfall on its coasts.

Experts believe that this situation indicates a major change in overall climate.

Cyclone Mocha could not ease the sweltering heatwave sweeping over the country since 2 April. Even when the cyclone hits, different parts of the country were experiencing scorching heat on Monday.

The intensity of heat may reduce a bit on Tuesday. However, heatwaves will continue in several areas of the country.

According to the world's meteorological agencies, the month of May could see more hotter days like in April. Not only in Bangladesh, these heatwaves are spreading from neighbouring states including West Bengal, Pakistan, Afghanistan to the East Asian countries of Myanmar, Vietnam, Laos and Thailand. It may continue intermittently throughout the rest of this month. Meteorologists assumed that May could be marked as the hottest month in recent history like last April.

Samarendra Karmakar, the former director and researcher of the meteorological department said Bangladesh has witnessed long heatwaves at various times before. But its continuance even after the cyclone indicates a major change in the weather patterns.

Cyclone expert Jeff Masters of National Oceanic and Atmospheric Administration (NOAA) and Yale University published an analysis immediately after the cyclone Mocha on Monday.

He described the cyclone as very strong and said that it weakened due to cold water and dry air in the Bay of Bengal near the Bangladesh coast. But in Myanmar it hits with a speed of 250 km per hour. Analysing the satellite images of the United Nations, he said that the clouds driven by the cyclone could not release any rain due to the dry air in Bangladesh. However, there has been heavy rain in Myanmar.

Meteorological researchers have blamed the heatwaves behind the lack of rain despite cyclone.

According to them, the cyclone lost its strength when it approached the Bangladesh territory as heatwaves were active in the vast area of South and East Asia including Bangladesh since April.

After the cyclone crossed the coast of Myanmar, the temperature started to rise again in the surrounding areas including Rakhine State in Myanmar. The situation in other countries is similar.

El Nino phenomenon develops

The National Oceanic and Atmospheric Administration (NOAA) and the United Nations Food and Agriculture Organization (FAO) have already predicted that the temperature will be high in various countries of the world including Australia and Asia.

According to the observations of various international meteorological organisations including NOAA, the La Nina situation was not active in the global climate for three years. When La Nina becomes active, there is heavy rainfall from the Pacific Ocean through the Indian Ocean to the Bay of Bengal.

But since this year, the weather has changed in those areas and El Nino conditions (warm ocean) are forming. This condition refers to high temperature and less rain. The weather may turn extreme. This condition has been leading to extreme temperature, as per the researchers.

Mohan Kumar Das, executive director of the National Oceanographic and Maritime Institute (NOAMI), told Prothom Alo on Monday that there are signs of El Niño conditions forming across the Bay from the Pacific Ocean. That's why the temperature is higher than normal this time.

The meteorological department's forecast for this month shows that the temperature may drop for a few days from Tuesday with rainfalls. However, the temperature may be above the normal in May. The maximum temperature in the country in May is usually around 33 degrees Celsius. It has already exceeded 35 degrees this time. The average temperature of the country was 2.2 degrees higher than normal in April as well.

Bajlur Rashid, a meteorologist of the meteorological department, said that the El Nino is active this time. Because of this, storms, rains and heatwaves are manifesting abnormally this year.

* This report, originally published in Prothom Alo print edition, has been rewritten in English by Farjana Liakat