Floods in desert lands, heat wave in Bengal with fog

In the desert countries of Oman and the United Arab Emirates, it's often said that it doesn't rain. However, both of these countries recently experienced record rainfall and devastating floods. Last Tuesday, from the roads to the airports, everything was submerged in water. In various cities of these two wealthy nations, expensive cars were seen submerged in the flow of water. The UAE's Meteorological Department states that such a quantity of rainfall hasn't been seen in the past 75 years. Now the question arises: why did such sudden rainfall occur in these desert countries? While some experts attribute it to cloud seeding, others blame La Niña. On the one hand, intense heatwaves are prevailing in South Asia, especially in West Bengal of India and Bangladesh, while on the other hand, thick fog has been descending in many districts of this region in the past few days. Many attributes, this unusual weather behavior to the influence of La Niña. However, there is no doubt among experts worldwide that climate change is responsible for this abnormal behavior of weather in the region of Middle East and Bengal.

What is cloud seeding, El Niño, and La Niña actually?
Cloud seeding, El Niño, and La Niña are all meteorological phenomena that influence weather patterns. Unsuitable rain clouds in the sky need to condense sufficiently to fall to the ground as rain. If it does not rain naturally, dry ice or silver iodide can be used to condense the clouds. The temperature of dry ice is minus 78 degrees Celsius. When this dry ice powder is spread on floating clouds, it condenses and falls to the ground as rain. This process is called cloud seeding.

El Nino means warm ocean currents in the Pacific Ocean. These currents warm the waters off the west coast of South America, especially towards Peru. At this time, the flow of tropical air in the southern hemisphere changes. Tropical air usually blows from Peru towards Australia. During El Nino conditions this wind flow slows down, stops or reverses its direction. Wind then blows from east to west. As a result, the ocean current that is supposed to carry the warm water towards Australia, also reverses its direction. Ocean currents carry warm water towards Peru, the west coast of South America. This water comes from the coast of Australia. As a result, water falls on the coast of Australia. And the sea temperature and height of the Peruvian coast increases. Due to these changes there is an upward circulation of air in Peru. Fluid displacement can occur in three ways. Transport, convection and radiation. Like water, air is a type of fluid. And when the wind moves upward, it takes the sea water with it. Delivers to the atmosphere. This water condenses at high pressure in the atmosphere, thereby lowering the temperature. Once it rained. That is, the rain that should normally occur in Australia, occurs in Peru.

What about Bangladesh, India or South Asia? When the tropical winds blow west rather than east, rainfall decreases over the entire region, from Australia to Bangladesh, India, and Myanmar. As a result, the airflow tends to carry ocean currents towards the west. Consequently, precipitation increases in the western direction. Conversely, regions spanning from Bangladesh, India, and Myanmar to Australia often experience a lack of rainfall. Temperatures rise, soil dries up, and even droughts may occur. However, scientists still don't precisely understand when or why El Niño occurs. We know that such changes happen due to alterations in airflow, but the exact reasons behind these changes remain unknown. Moreover, each El Niño event presents unique circumstances. The atmospheric reactions to El Niño vary each time, leading to unique circumstances with no specific pattern. Because of this variability and the absence of clear rules, scientists still haven't fully understood the reasons behind El Niño. Typically, El Niño events occur every 4 to 7 years, and they persist for about 12 to 18 months. However, currently, El Niño events are being observed more frequently.

The opposite phenomenon of El Niño is called La Niña. In years when La Niña occurs, the conditions in the Pacific Ocean become even more intense for the trade winds. During La Niña, the speed of the trade winds increases. As a result of the eastward airflow in Australia, heavy rainfall occurs. This effect extends to surrounding regions including Bangladesh, India, and Myanmar. Alongside heavy rainfall, flooding is often observed during this time. This trend has now extended beyond South Asia to encompass regions up to Middle East.

Why is there suddenly so much rain in desert countries like Oman and the United Arab Emirates?
Many attributes the widespread flooding in the United Arab Emirates last week to cloud seeding. The government of the country has been conducting cloud seeding operations since 2002, nearly 22 years, to address water security issues. The National Center of Meteorology in the United Arab Emirates sent cloud seeding aircraft from Al Ain Airport on Monday and Tuesday (April 15 and 16) with the aim of inducing rainfall. As a result, there was widespread rainfall on these two days. When life in the United Arab Emirates, including humans and other animals, is affected by heatwaves, the rainfall induced by cloud seeding is often referred to by the authorities as "blessed rain from Allah." However, excessive rainfall can lead to widespread flooding situations. In the United Arab Emirates, extreme controversy and criticism have arisen over this issue, directed towards the government. Last Tuesday, within a short span of 24 hours, the region of Al Ain recorded rainfall of 254.8 millimeters, whereas the average annual rainfall in the country ranges from 140 to 200 millimeters. In contrast, Dubai typically receives only about 97 millimeters of rainfall. The average monthly rainfall in April is usually just 8 millimeters.

On the other hand, neighboring country Oman has also experienced heavy rainfall, resulting in severe flooding. This has led to at least 18 fatalities in the country. Oman has also recently utilized cloud seeding technology. It has been reported that heavy rainfall occurred not only in Oman and the United Arab Emirates but also in Bahrain, Qatar, and Saudi Arabia on Tuesday and Wednesday.

However, many experts believe that La Niña's influence is causing heavy rainfall in desert countries as well. According to them, for the past nearly 22 years, cloud seeding programs have been conducted in countries such as Oman, Saudi Arabia, and the United Arab Emirates, among others in the Middle East. So why is there so much rainfall and intense flooding now?

They are stating that due to climate change, the La Niña effect has caused the formation of excessive upward airflow in the atmosphere of the Middle East, leading to the creation of unusually dense cloud cover. As a result, heavy rainfall has occurred through cloud seeding efforts. This has also contributed to the occurrence of floods in the region. Therefore, without the formation of unusually dense cloud cover due to the La Niña effect, such heavy rainfall would not have occurred solely due to cloud seeding.

Why are heatwaves and dense fog occurring together in Bangladesh?
Due to the influence of La Niña, the airflow is now shifting towards the west instead of the east. As a result, the amount of rainfall has decreased in the entire region encompassing Bangladesh, India, and Myanmar. This is because the wind flow is pushing moisture towards the western direction, leading to increased rainfall in the western areas. Consequently, the rainfall deficit has been observed from the eastern regions, starting from Bangladesh, India, and Myanmar to Australia. The temperature has risen, and the land is drying up. Drought conditions have been observed. On the other hand, due to the influence of La Niña, the amount of atmospheric moisture has increased significantly in Bangladesh this summer. Despite daytime temperatures, dense fog is occurring in several districts of this region from late night until dawn. Among these districts are Bakura, Bardhaman, Howrah, Kolkata, Cooch Behar, Darjeeling, and Jalpaiguri in West Bengal, as well as Panchagarh, Thakurgaon, Dinajpur, Rangpur, Nilphamari, Lalmonirhat, Kushtia, and Chuadanga districts in Bangladesh.

While Bangladesh is known as a country with a subtropical climate, unusual temperature behavior in recent years has challenged this perception. The Bangladesh Meteorological Department has reported that the highest recorded temperature in the Bengali region was documented at 42.3 degrees Celsius in 1960.

Since independence, the highest recorded temperature in Bangladesh was documented at 46.2 degrees Celsius in Rajshahi on May 30, 1972. In 1995, the temperature recorded was 43 degrees Celsius. On April 26, 2009, Jessore recorded the highest temperature in the past 14 years at 42.2 degrees Celsius. Despite the perception that temperatures are decreasing, the average highest recorded temperature in the past has been lower, while presently, it has increased significantly. The average temperature across Bangladesh, including the capital Dhaka, has increased by 1 degree Celsius from 1972 to January 2024. It's now quite clear that the creation of La Niña due to climate change is largely responsible for this.