As June begins and summer arrives, the heat that started in late May is gradually intensifying. Weather forecasts predict another extremely hot year due to global warming from climate change. Recent extreme temperatures approaching 50°C in northern India have already caused heat-related deaths. Meteorologists warn that this summer, the world will suffer from scorching sun and severe heat waves comparable to last year.
I used satellite imagery to assess Pyongyang’s summer heat and heat wave conditions. The analysis used satellite data from late summer 2024, which was recorded as a historic heat wave. I downloaded thermal infrared (TIR) images captured by the U.S. Earth observation satellite Landsat-9 from the U.S. Geological Survey (USGS) portal (EarthExplorer), specifically from a clear, cloudless day in late August. Late August is when late summer heat waves were at their peak.
South Korea’s weather service issues heat wave impact forecasts in four stages: watch, caution, warning, and danger. According to environmental health information from the Korea Environmental Industry and Technology Institute, heat wave alerts are classified by temperature and humidity levels. 
Based on Seoul’s humidity of 78% in late August last year, heat wave alert criteria can be divided into four categories as shown in the table to the right. At 78% humidity, temperatures of 29-30°C trigger watch alerts, 31-32°C trigger caution, 33-35°C trigger warnings, and 36°C or higher triggers danger-level heat wave alerts.
Pyongyang Heat Wave Analysis
I analyzed Pyongyang’s heat wave situation using thermal infrared data from the Landsat-9 satellite captured in late August 2024. On August 28, the average temperature was 26°C, ranging from a low of 20°C to a high of 38°C depending on the area. The analysis showed sweltering weather approaching 40°C. The total area covered by all four heat wave alert levels — danger, warning, caution, and attention — was approximately 24,000 hectares, accounting for 13.5% of Pyongyang.
Pyongyang’s heat wave zones were concentrated in the urban areas along both banks of the Taedong River, including Turusom, Yanggak Island, and Rungra Island. I examined the heat wave conditions in several major urban areas in detail.
I analyzed thermal infrared data and marked Pyongyang’s heat wave alert zones in purple to red by stage. In Pyongchon district, the Pyongyang Thermal Power Plant, Taedong River Battery Factory, and Pyongyang Station with surrounding areas were analyzed as suffering from intense heat and severe heat waves. In Taedong River district, the entire area was identified as purple-level or higher heat wave alert zones, with residential areas where people live marked particularly dark red. This appears to be a working-class neighborhood densely packed with low-rise housing. The residential complexes with houses crammed together without space between them seem to be heated by ground heat and radiating temperature. Hot air cannot escape and air circulation is poor, so these overcrowded residential areas appear as heat wave zones.
The phenomenon of working-class housing areas suffering from heat waves due to poor air circulation is similar to Seoul’s rooming house districts. Thermal infrared satellite data analysis shows that rooming house areas in Seoul’s Yeongdeungpo and Guro districts have high temperatures and high heat wave levels. If we analyzed New York’s Harlem using satellite data, it would likely be marked as a heat wave zone as well. Meanwhile, Seoul’s Jamsil apartment complex in Songpa district shows lower temperatures than surrounding areas in midsummer. This is because apartment complexes have wide spaces between buildings and air circulates through them, allowing hot air to escape.
Pyongyang’s Taedong River district has a diplomatic quarter with embassies. This is where various foreign embassy residences are concentrated, including those of Britain, Germany, Brazil, Yugoslavia, and Vietnam. Temperatures here are relatively lower than nearby residential areas. This is because buildings are spaced apart with open spaces like vacant lots between them, allowing hot air to escape and circulation to be relatively smooth.
In Pyongyang’s Yongsong district, there are residential facilities exclusively used by Kim Jong Un and his family. Called the Yongsong Villa or Yongsong Residence, the site includes an equestrian facility, shooting range, residence, restaurant, and a dedicated train station for Kim Jong Un. The Yongsong residence site measures 1,240 hectares, approximately 4.3 times the size of Yeouido (290 hectares). The residence boundaries reference data from American civilian satellite expert Jacob Bogle. According to Bogle, the Yongsong residence has triple-layered boundary fences strictly installed to block external intrusion. The residence has a restaurant where Japanese chef Fujimoto Kenji once lived and exclusively prepared high-end Japanese cuisine to suit Kim Jong Il’s particular Japanese food preferences. According to Fujimoto Kenji’s memoir, despite North Korea’s usual anti-Japanese rhetoric, Kim Jong Il and his family are known to have shown contradictory behavior, enjoying Japanese tastes and preferences and favoring Japanese culture and products.
Satellite photos show the Yongsong residence surrounded by dark green forests and greenery, with three large pond waterfront parks created in valleys, with the entire area having low temperatures and pleasant environmental conditions. The residence area shows temperatures of 25-26°C, a difference of more than 10°C from the heat wave weather exceeding 35°C outside the residence. Resting by waterside ponds and in green park forests while listening to birds and wind would seem optimal for a pleasant location. In Pyongyang, the cool, scenic, and pleasant prime locations in summer are occupied by the leader and his family’s private residences.
I summarized Pyongyang’s heat wave conditions by stage and organized the areas and ratios in the table. 
Pyongyang’s heat wave in late August last year was 65.7% in the “watch” category, 30.1% caution, 4.1% warning, and 0.1% in the highest danger level. The total heat wave area combining all four stages was 24,120 hectares, accounting for 13.5% of Pyongyang’s area. Pyongyang’s area was measured based on Geographic Information System (GIS) administrative district data and found to be 179,059 hectares. Pyongyang is quite large, about three times the size of Seoul (60,520 hectares).
