2023 was hottest year in recorded history, pouring rain and warming oceans

Children are seen playing in a fountain installed at Gwanghwamun Square in central Seoul in this file photo. (123rf)

South Korea experienced the hottest year in its recorded history in 2023, marking an all-time high in the average yearly temperature and among the most intense rains and hottest ocean temperatures in recorded history, according to the state weather agency.

The Korea Meteorological Administration on Tuesday announced its analysis of temperatures across the country, which showed that South Korea's yearly average was 13.7 degrees Celsius for last year, breaking the previous record of 13.4 degrees Celsius in 2016.

Both the average figure for daily high and daily low were the highest since the government started track in 1973, with the former recorded at 19.2 degrees Celsius and the latter at 8.9 degrees Celsius.

"High pressure in the atmosphere in the east of the country, including the north Pacific Ocean region, led to frequent flow of warm breeze blowing southward that resulted in high temperature," the KMA said.

To compare the climate indexes of a given year to past figures, the KMA extracts average figures for each index using the past 30 years of data. This average figure is announced once every 10 years and the currently-used one was released in 2021, based on data compiled between 1991 and 2020.

All months in 2023 had a higher average temperature than the 30-year average figures for the respective months, with March standing out with an average temperature of 9.3 degrees Celsius, 3.3 degrees higher than the 30-year average. Last year's summer was particularly brutal, as in the span of 52 days, from late July to early September, every day except one recorded an above-average temperature.

The heat wave in South Korea was not confined to land, but also affected its marine territory as well. The average sea surface temperature for last year was 17.5 degrees Celsius, which was substantially higher than the average figure of 17.1 for the past 10 years.

From 2014 to last year, only 2021 had a higher average sea surface temperature, at 17.7 degrees Celsius.

The record-high heat wave accompanied a higher-than-usual downpour, with an annual precipitation of 1,746 millimeters, the third highest since the government started recording in 1973.

But while 2023 did not have the most amount of rain overall, when it rained it poured. The rainfall intensity -- the annual precipitation divided by the days it rained -- was the highest-ever at 16.1 millimeters.

South Korea also had 2.9 days when it rained at least 30 millimeters an hour, and 3.8 days when it rained more than 80 millimeters, both the second highest ever.

The year 2023 was not only the hottest-ever year for South Korea but was also for the planet, as confirmed by last Friday's report from the World Meteorological Organization. Using the six international datasets, UN-affiliated organization said the global average annual temperature was 1.45 (plus or minus 0.12) degrees Celsius above pre-industrial levels (1850-1900) last year.

The global temperature set a new monthly record in every month between June and December, while July and August were the two hottest months ever across the planet.

The latest report shows that the Earth is very rapidly approaching the temperature threshold set by the 2015 Paris Agreement on climate change, in which the 196 parties agreed to maintain the global temperature well below 2 degrees Celsius above pre-industrial levels and preferably below 1.5 degrees above the figure.

WMO Secretary-General Celeste Saulo urged international efforts to address climate change while presenting the findings. She stressed the need for drastic reductions in greenhouse gas emissions and the accelerated transition to renewable energy sources.

By Yoon Min-sik(minsikyoon@heraldcorp.com)