Summer has gotten longer 20 days in 100 years

Summer on the Korean Peninsula has been extended by 20 days in 100 years. The longest season of the year on the Korean Peninsula used to be winter but it gave way to summer.

The Korea Meteorological Administration (KMA) on Wednesday announced its analysis on long-term trends in climate change. The weather agency compared the average temperature of six cities including Seoul, Daegu, Incheon, Mokpo, and Gangneung in the 30 years from 1912 to 1940 to the average temperature of those cities in the last 30 years from 1991 to 2020. The KMA has been observing the temperature of those six cities over 100 years.

The average annual temperature of the Korean Peninsula has recently increased by 1.6 degrees Celsius compared to the past, showing evident signs of global warming. As for average lengths of seasons, summer turned out to be the longest season in recent years with 118 days, followed by spring (91 days), winter (87 days), and fall (69) days. In the past, winter used to be the longest season with 109 days, followed by summer (98), spring (85), and fall (73 days). The order changed with summer getting longer by 20 days and winter getting shorter by 22 days.

The onset of spring and summer has become faster by 17 days and 11 days, respectively. Spring used to begin on March 18 but it has begun on March 1 in recent years. Summer began in mid-June in the past but the date has been moved forward to late May in recent years. For this reason, the blooming of cherry blossoms in Seoul began on March 24, the earliest date on record since observation began in 1922. On the other hand, the onset of fall and winter has been pushed back by nine days and five days, respectively.

As global warming continues, there have been changes to 24 seasonal divisions of a year. The 30-year average temperature of Daehan (around Jan. 20), the coldest day of the year, was 0.9 degrees Celsius, warmer than 0.8 degrees Celsius of Sohan (around Jan. 5). The proverb, “Daehan froze to death at Sohan’s house” now makes sense. In past 30 years, Daehan used to be colder than Sohan. The KMA said its temperature observation for over 100 years shows that temperatures are rising in all seasons and seasonal divisions.


kej09@donga.com