-Professor Seung-Ki Min and his research team studied human contribution to the longest duration of 2018 summer heat wave in South Korea.
– Global warming at least quadrupled probability of the long-lasting heat wave. “As global warming continues, long-lasting heat waves will become more frequent.”

In the summer of 2018, South Korea had the strongest and longest heat wave in its meteorological observation history, breaking records with the highest temperature in Seoul at 39.5°C, 31.5 hot days and 17.7 tropical nights on average over the country. This extremely long-lasting heat wave impacted greatly on its national economy with the net loss of about 68 million US dollars, with 4,526 people suffering heat-related illness, and deaths of 48 people, 9.1 million domestic animals, and 7.1 million fish.

Professor Seung-Ki Min, researcher professor Yeon-Hee Kim, and PhD student Sang-Min Lee identified the human impact on the duration of heat wave in South Korea for the first time. Through joint work with the climate modeling teams in the University of Oxford and the Met Office of United Kingdom, they showed that greenhouse warming has increased the probability of the heat wave occurrence with strong intensity and long duration as the one in 2018 by at least four times. Their study has been published in the special issue “Explaining extreme events of 2018 from a climate perspective” of the Bulletin of the American Meteorological Society.

There have been many studies demonstrating that greenhouse gas increases induce stronger and frequent heat wave. However, it has been difficult to find scientific evidence that links the longer duration of heat wave with global warming due to the limited observations and climate model experiments. This research proved for the first time that the heat wave indeed become longer by human activities.

To understand the impact of global warming on the duration of heat wave in South Korea, the research team performed high-resolution climate model experiments. They simulated the climate model with and without human-induced greenhouse gas increases thousands of times repeatedly and compared the heat wave probabilities. As a result, they concluded that long-lasting heat wave like the one occurred in the summer of 2018 is caused by anthropogenic global warming with probability of its occurrence increased over four times.

Professor Seung-Ki Min commented, “We quantified human impact on long-lasting heat wave in South Korea by analyzing large amount of data from the high-resolution climate model simulations. As global warming continues, we will be experiencing such heat waves more frequently, so our society needs a careful preparation for the unprecedented situation.”

This research was supported by the Korea Meteorological Administration, National Institute of Meteorological Science and National Research Foundation of Korea.