Low-level easterly winds blowing through the Tsugaru Strait, Japan. Part II: Numerical simulation of the event on 5-10 June 2003
Low-level easterly winds blowing through the Tsugaru Strait, Japan. Part II: Numerical simulation of the event on 5-10 June 2003
复制标题
日本津轻海峡吹低层东风。
DOI：
10.1175/mwr-d-11-00035.1
复制
发表时间：
2012
影响因子：
3.2
通讯作者：
and Hiroshi Kawamura
中科院分区：
文献类型：
--
作者：
Teruhisa Shimada;Masahiro Sawada,Weiming Sha;and Hiroshi Kawamura
本文利用数值天气预报模式研究了2003年6月5-10日经过津轻海峡和陆津湾的低空东风的结构和日变化。由于鄂霍次克高压的持续存在，伴随着盛行东风的冷空气在夜间侵入海峡和海湾500米以下，并在白天撤退。这种冷空气的入侵和撤退导致在海峡的东入口，陆津湾，在海峡的西出口的风的日变化。在东入口，白天海峡内气温的上升与流入的冷空气产生了很大的空气温差，由此产生的压力梯度力加速了风。流入陆津湾的冷空气在白天进入海湾之前在陆地上被加热。由此产生的冷空气深度和气压梯度力的变化加强了白天的风。在西出口处，日本海暖空气和海峡内冷空气之间的空气温度差以及低层冷空气深度的变化引起了局地气压梯度力扰动。西出口的加速风在白天接近地转平衡向西南方向延伸，在夜间由于科里奥利效应的主导作用而经历轻微的反气旋旋转向西风。
This paper investigates the structures of and diurnal variations in low-level easterly winds blowing through the Tsugaru Strait and Mutsu Bay on 5–10 June 2003 using a numerical weather prediction model. Cool air that accompanies prevailing easterly winds owing to the persistence of the Okhotsk high intrudes into the strait and the bay below 500 m during the nighttime and retreats during the daytime. This cool-air intrusion and retreat induce diurnal variations in the winds in the east inlet of the strait, in Mutsu Bay, and in the west exit of the strait. In the east inlet, a daytime increase in air temperature within the strait produces a large air temperature difference with the inflowing cool air, and the resulting pressure gradient force accelerates the winds. The cool air flowing into Mutsu Bay is heated over land before entering the bay during the daytime. The resulting changes in cool-air depth and in pressure gradient force strengthen the daytime winds. In the west exit, local pressure gradient force perturbations are induced by the air temperature difference between warm air over the Japan Sea and cool air within the strait, and by variations in the depth of low-level cool air. The accelerated winds in the west exit extend southwestward in close to geostrophic balance during the daytime and undergo a slight anticyclonic rotation to westerly during the nighttime owing to the dominance of the Coriolis effect.