Is it due to global warming? Natural disasters seem to be becoming more severe, with larger and more devastating impacts. Recently, Assoc. Prof. Sonthi Kochawat, an expert in environmental and health sciences, posted an explanation about the phenomenon of “cloudbursts,” which is the cause of the heavy rainfall.
The heavy, continuous rainfall lasting for 4 hours near the foothills caused flash floods and severe flooding in Ban Rai District, Uthai Thani Province. Assoc. Prof. Sonthi speculates that the massive damage could be attributed to the phenomenon of Cloudburst or Rain Bombs, resulting in heavy rain.
The professor explains that cloudbursts cause intense rainfall (Rain Bombs), which will occur more frequently in Thailand during the rainy season.
Cloudbursts typically happen near foothill areas where the temperature difference between the air at the ground level and the air at the peak is significant. This causes warm air or low-pressure air near the foothills to move upwards towards the cooler air at the peak, rapidly cooling the air near the surface. This results in increased relative humidity and more water vapor, which eventually condenses into clouds.
Additionally, the wind at lower levels gathers scattered clouds and accumulates them at the foothills, forming large, moisture-heavy clouds. When cold air from the ocean or continental areas clashes with these clouds, it leads to the cloudburst phenomenon, causing water condensation and turning into heavy rainfall, or “Rain Bombs,” which can cause sudden flooding.
“From now on, the occurrence of cloudbursts and heavy rain in specific areas will happen more frequently, especially in areas with diverse topography, such as high mountains with dense forests or cities with tall buildings. This will increase the temperature difference between the ground and the higher levels.”
The occurrence of the “cloudburst” phenomenon is difficult to predict due to the intensifying global warming, which causes more volatile weather. It also increases the evaporation of water from oceans and seas, leading to more moisture in the air than usual.
Furthermore, it causes a greater temperature difference between the ground and higher levels. As a result, the occurrence of cloudbursts and intense rainfall becomes more unpredictable but usually happens when a low-pressure monsoon trough passes through or when cold air masses from the mainland or oceans collide.
Assoc. Prof. Sonthi predicts that in November, the high-pressure air mass or cold air from the mainland will become stronger, and the monsoon trough will shift to the lower southern region, reducing such phenomena.
“However, the cold air mass, which is high pressure, will press down on the air near the surface of the Earth, reducing the vertical dispersion of pollutants from various sources on the ground, which will cause PM2.5 dust levels to rise again.”
CR.https://www.springnews.co.th/keep-the-world/climate-change/853514
