Japan Geoscience Union Meeting 2025

Presentation information

[E] Oral

A (Atmospheric and Hydrospheric Sciences ) » A-CG Complex & General

[A-CG44] Terrestrial monitoring using geostationary satellites

Wed. May 28, 2025 10:45 AM - 12:15 PM Exhibition Hall Special Setting (5) (Exhibition Hall 7&8, Makuhari Messe)

convener:Yuhei Yamamoto(Center for Environmental Remote Sensing, Chiba University), Tomoaki Miura(Univ Hawaii), Kazuhito Ichii(Chiba University), Chairperson:Yuhei Yamamoto(Center for Environmental Remote Sensing, Chiba University)

11:45 AM - 12:00 PM

[ACG44-09] Post-Typhoon Extreme Heat Events: Land Surface Temperature Variability and Urban Land Use Influences

*Yuhei Yamamoto1, Kanato Mawatari1, Kazuhito Ichii1 (1.Center for Environmental Remote Sensing, Chiba University)

Keywords:Extreme heat, Typhoon, Himawari, geostationary satellite, Land surface temperature, Urban land use

With the progression of climate change, the increasing frequency and intensity of typhoons and heatwaves have raised concerns about the heightened risk of compound heatwave events. Extreme heat induced by typhoons can be attributed to foehn effects and post-typhoon clear-sky heating. Previous studies on compound heatwaves have primarily utilized numerical models, focusing on their occurrence frequency and the dynamic effects of foehn winds. However, there is still limited understanding of the clear-sky conditions following typhoon passage. In Japan, heatstroke incidents have been reported following typhoon passage, underscoring the scientific and societal importance of understanding post-typhoon thermal environment variations.

This study examines the thermal environment in the Kanto region following the passage of Typhoon Faxai (2019), with a focus on the variability of land surface temperature (LST) before and after the typhoon. The LST data were retrieved from Himawari-8 geostationary satellite data with 10-min frequency. To investigate surface heating efficiency, we used solar radiation data estimated from Himawari-8 and urban land use data.

A comparative analysis of LST before and after the typhoon revealed widespread temperature increases across Kanto, with inland areas experiencing temperature rises exceeding 6 °C. Wind speeds remained generally weak, indicating that advection played a minimal role in the temperature increases. The surface heating efficiency to cumulative solar radiation during forenoon was particularly high in areas with low-rise buildings, suggesting that land-use patterns contributed to extreme heat formation. These findings highlight the need for further investigation into post-typhoon thermal environments to improve heat risk mitigation strategies in urban areas.