Future changes in summertime precipitation in Japan associated with topography
Abstract
This study investigated future changes in summertime precipitation amounts in Japan and their relations to the topography by analyzing data from 20-km resolution regional climate scenarios in the periods of 1981-2000 and 2081-2100, obtained from three different RCMs. Results of the analyses indicated that future increases in precipitation are noticeable in the west and south sides of the mountainous regions especially in Western Japan. The large precipitation increases are likely to occur not only in high altitude areas but also at low altitudes including urban areas. In such areas, the frequencies of precipitation amounts greater than 50 and 100 mm day-1 would also increase under the future climate. The main cause of these precipitation changes is considered to be intensification of southwesterly moist airflow, which is likely to be associated with future increases of north-south gradient of atmospheric pressures especially in the region located to the south of 35°N. The intensified southwesterly moist airflow that impinges on the western and southern slopes of the mountains could generate stronger upslope flows and well-developed clouds, leading to the larger precipitation. In contrast, the precipitation changes in the lee sides of the mountainous regions would be comparatively small.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2012
- Bibcode:
- 2012AGUFM.A41H0060T
- Keywords:
-
- 1637 GLOBAL CHANGE / Regional climate change