11:15 AM - 11:30 AM
[AAS07-03] Summertime hot weather zone classification for Japanese urban cities.
Keywords:Hot weather, Climate zone classification
This study proposed a summertime extremely hot weather classification focusing on Tokyo, 62 ordinance-designated cities, and 20 core cites in Japan by using a self-organizing map (SOM), which represented frequently occurred patterns mapped onto two-dimensional latent space. We first created the 10 x 10 SOM map based on the daily sea-level pressure data for the domain of 120-150E x 20-50N in June 1 to September 30 from 1960 to 2020. We next picked up the days with the daily maximum temperature exceeding 30 C for JMA’s AMeDAS observation sites nearest to each targeted city (allowing site duplication). Matching the hot days with SOM classifications allowed us to unveil the synoptic characteristics when experiencing high temperatures in each city. We moreover performed hierarchical grouping of the results based on a typical hot-day feature frequently occurred within similar weather patterns.
A general feature of the hot-day weather pattern is characterized by a high-south, low-north pressure pattern and a typhoon over the southern coast. The patterns were divided into two major climatic zones, the northern and the southern Japan type. We further identified seven minor climate zones: Western Coast of Northern Japan, Eastern Coast of Northern Japan, Kanto, San'in-Hokuriku-Inland, Setouchi-Northern Kyushu, Nankai, and Hakodate-Iwaki. Although almost all minor climate zones were consistent with the Japanese climate zones geographically advocated, this study demonstrated that the statistical analysis could objectively classify the zones associated with the extremely hot weather.
A general feature of the hot-day weather pattern is characterized by a high-south, low-north pressure pattern and a typhoon over the southern coast. The patterns were divided into two major climatic zones, the northern and the southern Japan type. We further identified seven minor climate zones: Western Coast of Northern Japan, Eastern Coast of Northern Japan, Kanto, San'in-Hokuriku-Inland, Setouchi-Northern Kyushu, Nankai, and Hakodate-Iwaki. Although almost all minor climate zones were consistent with the Japanese climate zones geographically advocated, this study demonstrated that the statistical analysis could objectively classify the zones associated with the extremely hot weather.