[대기] [대기과학세미나] Prof. Satoru Okajima (University of Tsukuba)
일시 : 2025-03-04(화) 16:00 ~ 17:00
연사 : Prof. Satoru Okajima
소속 : University of Tsukuba
문의 : 02-880-6723
장소 : 501동 504호 세미나실
Title: Transient eddy activity in midlatitudes: seasonality and air-sea interactions
Abstract: Transient eddies (migratory cyclones and anticyclones) are pivotal in both weather and climate in the extratropics. They account for most of the day-to-day weather variability and maintain background fields through their interaction with longer-scale atmospheric circulation variations and jet streams. Areas of vigorous transient eddy activity, called "storm tracks", are collocated well with regions of large lower-tropospheric baroclinicity. However, the seasonality of transient eddy activity and that of baroclinicity do not always correspond well with each other. In this seminar, we will explore the results of studies on the distinctive seasonality of the transient eddy activity of oceanic storm tracks by comparing methods based on tracking individual cyclones/anticyclones and those based on temporally filtered local eddy statistics. Additionally, we will explore the role of atmospheric transient eddies in the midlatitude air-sea interactions. By quantifying the contributions of cyclones and anticyclones to climatological-mean heat and moisture supply from the ocean and rainfall along the two major oceanic frontal zones over the North Pacific and North Atlantic, we demonstrate that oceanic frontal zones climatologically act to strengthen the hydrological cycle between cyclones and anticyclones.
Abstract: Transient eddies (migratory cyclones and anticyclones) are pivotal in both weather and climate in the extratropics. They account for most of the day-to-day weather variability and maintain background fields through their interaction with longer-scale atmospheric circulation variations and jet streams. Areas of vigorous transient eddy activity, called "storm tracks", are collocated well with regions of large lower-tropospheric baroclinicity. However, the seasonality of transient eddy activity and that of baroclinicity do not always correspond well with each other. In this seminar, we will explore the results of studies on the distinctive seasonality of the transient eddy activity of oceanic storm tracks by comparing methods based on tracking individual cyclones/anticyclones and those based on temporally filtered local eddy statistics. Additionally, we will explore the role of atmospheric transient eddies in the midlatitude air-sea interactions. By quantifying the contributions of cyclones and anticyclones to climatological-mean heat and moisture supply from the ocean and rainfall along the two major oceanic frontal zones over the North Pacific and North Atlantic, we demonstrate that oceanic frontal zones climatologically act to strengthen the hydrological cycle between cyclones and anticyclones.
첨부파일 (1개)
- Abstract (Prof. Satoru Okajima).pdf (32 KB, download:3)
