Down to Earth –
A shorter-than-normal monsoon, below-average rainfall, and El Nino condition leading to abnormally high temperatures drove Thailand to its worst drought in more than 40 years.
A map released by the United States National Aeronautics and Space Administration’s (NASA) Earth Observatory on February 15, 2020 showed below-normal subsurface soil moisture in large parts of southeast Asia. Lower Mekong Basin countries, including Laos, Cambodia and Vietnam were all affected by a delayed and short monsoon, according to the Mekong River Commission. But Thailand was the worst hit. An El Nino event also led to increased temperatures and high evapotranspiration in the region.
NASA’s Soil Moisture Active Passive (SMAP) mission measures water content of soils and can detect water in the top five centimeters of the ground.
The drought has exhausted the southeast Asian country’s major reservoirs, which held less than half the water they could. River water levels were so low that salt water from seas entered them, affecting drinking water supplies. Low-lying areas have been the worst-affected by salt water intrusion.
“This is one of the signs showing the drought situation in low-lying areas in Thailand this year is worse than before,” said Senaka Basnayake, director of Climate Resilience at the Asian Disaster Preparedness Center in Thailand.