Data released by the Korea Disease Control and Prevention Agency on August 4th showed that as of the 3rd, a total of 2,221 cases of heat-related illnesses had been reported nationwide, with 19 fatalities. President Lee Jae-myung has called for a fundamental overhaul of the national crisis management system to cope with the increasingly normalized threat of extreme weather.
On the morning of August 4th, the capital city of Seoul issued its first-ever “Heat Wave Major Alert,” the highest level of warning, and fully activated three emergency response measures: “work stoppage, cooling, and care.”
The Korea Meteorological Administration explained that the “Heat Wave Major Alert” is a newly established top-tier warning introduced on June 1st this year. It is triggered when the maximum perceived temperature exceeds 35 degrees Celsius for two consecutive days, or when the maximum perceived temperature hits 38 degrees Celsius, or the actual air temperature soars past 39 degrees Celsius.
This marks the first time Seoul has entered a state of major heat alert since the system’s implementation. Previously, South Korea’s heat warnings were only divided into two levels—”Heat Wave Advisory” and “Heat Wave Warning”—which proved inadequate for the increasingly extreme heat seen in recent years.
Additionally, seven cities and counties in Gyeonggi Province also issued their first-ever highest-level heat alerts. The provincial government elevated its emergency response for heat-related disasters to Level 2 and mandated a halt to outdoor construction work during the hottest hours of the day. On the same day, major alerts were also declared in Jeonju (North Jeolla Province), Yeosu, Gwangyang, Suncheon (South Jeolla Province), and the city of Gwangju.
Previously, the Korea Meteorological Administration noted that many parts of the country experienced temperatures exceeding 40 degrees Celsius on August 2nd. In Yangsan, South Gyeongsang Province, daytime temperatures topped 40 degrees for five consecutive days, eventually climbing to a record-breaking 42.5 degrees Celsius.
As the relentless heat persists, the number of heatstroke patients continues to rise, with multiple cases of cardiac arrest and death being reported.
Meteorologists point to a rare and simultaneous overlap of the North Pacific subtropical high-pressure system and the Tibetan high-pressure system over the Korean Peninsula. This created a stable descending air mass that acted like a giant lid, trapping ground-level heat and directly fueling this historic heatwave.
The Korean Peninsula is situated at a relatively high latitude. Throughout the last century, summer temperatures averaged a comfortable 22-27°C, with August typically being the hottest month. Historically, the average number of summer days with temperatures at or above 33°C was fewer than eight.
Due to global warming, climate change on the peninsula has become increasingly evident, characterized by rising temperatures, sea-level rise, and a spike in extreme weather events. South Korea’s summers, in particular, are trending towards being “longer and hotter.”
Over the past five years, South Korea has averaged 19 heatwave days annually—more than double the average from the 1970s. This year, the return of the El Niño phenomenon has caused abnormally high sea surface temperatures in the waters around the peninsula. Combined with the downslope wind effect (foehn wind) from the country’s mountainous terrain, these factors culminated in the 42.5°C record high.
During a State Council meeting held yesterday at the presidential office, Lee Jae-myung stated that the record-breaking temperatures across the country are causing immense difficulties for citizens’ daily lives. He emphasized the need to treat the current situation as a “national disaster state,” fundamentally redesigning the disaster response framework and raising public awareness about the risks of extreme heat.
On another front, authoritative institutions and climate scientists have recently issued warnings that the strengthening El Niño in the Pacific, combined with human-induced warming, is triggering extreme weather across the globe. This El Niño event is projected to be one of the most powerful in 150 years.
Given these two converging factors, global average temperatures in 2027 are likely to rise 1.7°C above pre-industrial levels, breaching the 1.5°C threshold that nations pledged to strive to avoid under the Paris Agreement.
El Niño is a climate phenomenon characterized by the abnormal warming of sea surface temperatures in the central and eastern equatorial Pacific. It disrupts global atmospheric circulation, leading to anomalous weather patterns in different regions and having profound impacts on global agriculture, ecosystems, and livelihoods.