Ryoga Hiroki, Alvin C. G. Varquez, Do Ngoc Khanh, Ryza Rynazal, Florent Renard, Lucille Alonso, Manabu Kanda
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引用次数: 0
Abstract
Evaluating long-term changes in thermal comfort can be useful for considering measures against thermal-related health risks. In this study, spatio-temporal changes in thermal comfort, using the Universal Thermal Climate Index (UTCI), were calculated from observations at 140 weather stations across Japan for the 1980–2020 period. To derive the mean radiant temperature (MRT) values not readily measured at the stations but required in the estimation of UTCI, a machine-learning model (XGBoost) was developed. The model uses the station observations, coarse-resolution radiation data from the ERA-5 reanalyses dataset, and available globe temperature measurements as predictors. The trend of UTCI throughout Japan in summer was found to be significantly positive. Meanwhile, negative trends were found in stations located in northern areas during the winter. This suggests that not only heat stress risks but also cold stress risks should be given careful attention in colder regions. Lastly, a comparison of the estimated UTCI with prefecture-level daily summertime heat-stroke data reveals that the UTCI threshold above which heat-stroke cases rise drastically varies distinctly between warm and cold regions, with the latter having a lower threshold. These findings could contribute to the estimation of risks attributable to climate change and to better planning of climate-change-resilient cities.
期刊介绍:
The International Journal of Climatology aims to span the well established but rapidly growing field of climatology, through the publication of research papers, short communications, major reviews of progress and reviews of new books and reports in the area of climate science. The Journal’s main role is to stimulate and report research in climatology, from the expansive fields of the atmospheric, biophysical, engineering and social sciences. Coverage includes: Climate system science; Local to global scale climate observations and modelling; Seasonal to interannual climate prediction; Climatic variability and climate change; Synoptic, dynamic and urban climatology, hydroclimatology, human bioclimatology, ecoclimatology, dendroclimatology, palaeoclimatology, marine climatology and atmosphere-ocean interactions; Application of climatological knowledge to environmental assessment and management and economic production; Climate and society interactions