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[Asia Economy Reporter Lim Cheol-young] The temperature in urban areas was found to be on average 2.32℃ higher than mountainous areas and 1.08℃ higher than riverside areas from April to August, and 2.16℃ higher than mountainous areas and 1.42℃ higher than riverside areas from November to March. During the summer, urban areas exhibited characteristics of experiencing discomfort earlier and for a longer duration compared to mountainous or riverside areas.

According to Seoul City on the 2nd, an analysis conducted over the past year using the IoT (Internet of Things) urban data platform S-DoT revealed that Seoul’s urban center is approximately 2.32℃ warmer than mountainous areas in summer and about 2.16℃ warmer in winter. The discomfort index in urban areas during summer was observed to rise 2 to 3 weeks earlier than in mountainous areas and to persist for a longer period. Seoul City compared temperature, humidity, fine dust, discomfort index, and heat index data collected over one year from S-DoT devices installed in major mountainous areas and riversides within the city and from nearby urban centers to identify differences in living environments according to urban area characteristics.

In particular, on the clearest and hottest days last year (June 22 and August 26), urban areas were on average 3 to 3.4℃, and up to 7℃, warmer than mountainous areas, and 1.6 to 1.9℃, and up to 4.3℃, warmer than riverside areas. On the clearest and coldest days last winter (December 15 and January 8), urban areas were on average 1.7℃, and up to 5.3℃, warmer than mountainous areas, and 1.6℃, and up to 4.6℃, warmer than riverside areas. Additionally, on days with heavy snowfall (December 29 and January 5), urban areas were on average 1.6 to 2.3℃, and up to 6.9℃, warmer than mountainous areas, and 1.8 to 2.2℃, and up to 4.6℃, warmer than riverside areas.

The temperature and humidity measurements from the Seoul Meteorological Observatory showed similar trends to those recorded by S-DoT devices installed around mountainous areas within Seoul. A Seoul City official explained, "The higher temperatures recorded by S-DoT devices installed in urban centers compared to those in mountainous areas suggest that the living environment temperature in urban areas where many citizens reside is somewhat higher than the meteorological observatory measurements, while humidity is somewhat lower."

Consequently, urban areas experienced discomfort earlier and for a longer duration than mountainous or riverside areas during summer. Weekly analysis of S-DoT measurement data from mountainous, riverside, and nearby urban areas showed that the discomfort index in urban areas rose one to two weeks earlier than in riverside areas and two to three weeks earlier than in mountainous areas, indicating an earlier onset of higher discomfort levels.

In winter, fine dust levels were lower in mountainous areas than in urban centers, while fine dust measurements in urban, mountainous, and riverside areas were generally similar during other seasons. During winter, fine dust in mountainous areas was on average 11.5 ug/㎥ lower than in nearby urban areas from November to March, and about 15 ug/㎥ lower in February and March, showing a significant difference. Riverside and urban areas generally showed similar measurements.

Outside of winter, fine dust measurements across urban, riverside, and mountainous areas showed generally similar trends. Regardless of regional characteristics, areas undergoing construction showed fine dust levels approximately twice as high as neighboring areas during the construction period (June to October).

Meanwhile, Seoul City stated that based on the analysis of S-DoT measurement data linked to the direct and indirect effects of a 1℃ temperature change on citizens’ lives, urban centers are expected to incur increased cooling costs in summer (on average 1 to 3℃ warmer than mountainous or riverside areas), but also to benefit from reduced heating costs in winter (on average 1 to 2℃ warmer).

Furthermore, the S-DoT data analysis indicated that due to the prolonged higher discomfort levels in urban areas compared to mountainous or riverside areas during summer, there is a relatively higher likelihood of violent crimes, serious crimes, and traffic accidents in urban centers. This underscores the need for preventive activities to reduce incidents and accidents in urban areas during summer. Since urban areas have higher heat indices and longer-lasting tropical nights compared to mountainous or riverside areas, enhanced management of the elderly, vulnerable populations, and socially isolated single-person households during heatwaves is also necessary.

Lee Won-mok, Director of Seoul City’s Smart City Policy Division, said, "S-DoT sensors serve as an optimal infrastructure to closely monitor urban phenomena," adding, "We will integrate and analyze diverse S-DoT sensor data measured throughout Seoul along with data from the public, private, and academic sectors to develop services and policies that citizens can feel and that enhance the value of the city."

This content was produced with the assistance of AI translation services.