The globe hit by the ‘heat dome’

The whole globe seems to be suffering from a "heat dome." A heat dome is a stagnant or slowly moving high-pressure ridge at the upper-middle layer of the atmosphere that traps hot air under it, bringing extreme hot weather. In America, 26 states have been warned of a heat wave, the highest temperature recording 46.1 degrees Celsius. The southeastern regions of China including Zhejiang, Fujian and Shanghai have also seen their temperature hike at around 40 degrees Celsius. The World Meteorological Organization projected Monday that this year is likely to be the hottest one since weather observation began.

Korea is no exception. The average temperature in May this year was 18.6 degrees Celsius, the highest since record, and June came a third at 22.3 degrees Celsius. July's average temperature until July 20 was 24.3 degrees Celsius, higher than the same month in the previous year (23.8 degrees Celsius). Global warming, super El Niño, and the hot and humid air in the Pacific Ocean all contributed to turning the whole Korean Peninsula into a sauna. The weather forecast had predicted seasonal rain, but there is no sign of rain at present.

Dr. Lance Workman at the University of Glamorgan in the UK found that excessive heat increases violent behavior by boosting serotonin secretion in our brain. A heated brain is also reported to pump more adrenalin from the hypothalamus, which is responsible for controlling body temperature. Most big riots in history took place when the temperature was between 23 and 31 degrees Celsius. That said, the recent series of growing tensions between police and African Americans in the U.S. may also have something to do with the hot weather. However, when the temperature goes beyond 31 degrees Celsius, violent accidents tend to happen less, probably because people are often too tired to even fight.

“They say the summer is better than the winter for poor people, but prisoners prefer cold weather,” Korean author Shin Young-bok said in his book “Letters from the prison.” He pointed out that the hot weather in summer triggers hate among inmates. Actual statistics support that the death toll is higher in extreme hot weather than in the cold. Fox News advised to eat breakfast, drink much water, eat frequently by small portions, and take a light walk in order to recover energy in summer. You might want to go out to a nearby park instead of staying in the air conditioned room all day.

정성희기자 shchung@donga.com