Cloud microphysical processes in heavy snowfalls caused by an intensified broad cloud band over the Sea of Japan

2014 Fiscal Year Final Research Report

• Project/Area Number: 24740319
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Meteorology/Physical oceanography/Hydrology
• Research Institution: Nagoya University
• Principal Investigator: OHIGASHI Tadayasu 名古屋大学, 地球水循環研究センター, 特任助教 (80464155)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 帯状雲 / 雲微物理 / 降雪機構 / 霰 / 雪片 / 氷晶 / 偏波レーダー / 日本海

Outline of Final Research Achievements

Broad cloud bands, that are considerably thicker than cloud streaks covering over the sea, are formed over the Sea of Japan during cold-air outbreaks. Broad cloud bands largely vary with time and space. In especially intensified time and space, heavy snowfalls occur. An broad cloud band was formed for about 2 days from 25 January 2009 and was largely intensified in the landing part. In this study, formation processes of snowfall particles (cloud microphysical processes) in an intensified broad cloud band were studied mainly using a polarimetric radar. A local low-level stationary convergence region was caused on a flank of a mountain region by a mountain blocking effect. In the region, increase of graupel precipitation resulted in a heavy snowfall.

Free Research Field

気象学