Scientists have been informing people that the frequency and intensity of extreme events will increase in the future with the increased global mean temperature. In April 2016, Southeast Asia experienced an extreme high-temperature event, in which the maximum temperature in each day of April in Thailand all exceeded 40°C and the duration of scorching weather in 2016 set a new record after 1950s. The high-temperature event also caused Thailand to suffer serve drought in March of 2017 and 2019, and even the worst drought in possibly four decades in March 2020.
Thailand is one of the most popular travel destinations in the world but it's also vulnerable to heatwaves. (Image by DONG Zizhen)
The Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) suggested that the increases in the seasonal and annual mean temperature are expected to be more prominent in the tropics and subtropics than in mid-latitudes. It implies that Southeast Asia may suffer more from global warming than other regions of Asia. However, it is not clear how heatwaves in Southeast Asia will change under global warming.
To address this issue, a PhD. student DONG Zizhen working with Prof. WANG Lin in the Institute of Atmospheric Physics, Chinese Academy of Sciences, published their study in Earth's Future
. Based on the bias-corrected model outputs from the Community Earth System Model Large Ensemble project, they estimated the changes in Southeast Asian heatwaves under different global warming levels. According to their study, the projected warmer future tends to be associated with more frequent heatwaves, longer heatwave duration, and higher extreme temperature in Southeast Asia. The changes in heatwave characteristics have distinct regional differences in response to global warming between the Maritime Continent and Indochina Peninsula due to the different heat content of lower atmospheric boundaries.
WANG Lin, the corresponding author of the work, warned, "the extreme heatwave event, such as the heatwave that happens only once-in-50-years and is rare in the current climate, will become more frequent in a warmer future, and may happen once a year in Southeast Asia."
The work was supported by the National Natural Science Foundation of China (41925020, 41721004, 41661144016).
Dong, Z., Wang, L., Sun, Y., Hu, T., Limsakul, A., Singhruck, P., & Pimonsree, S. (2021). Heatwaves in Southeast Asia and their changes in a warmer world. Earth's Future, 9, e2021EF001992. https://doi.org/10.1029/2021EF001992