东亚—西北太平洋海平面气压场的动力特征分析  

Dynamic Properties of Sea Level Pressure Field in East Asia–Northwest Pacific

作　　者：孙宇 韩琳[1] 李建平 丁瑞强 SUN Yu;HAN Lin;LI Jianping;DING Ruiqiang(Chengdu University of Information Technology,Chengdu 610225;Key Laboratory of Physical Oceanography of the Ministry of Education,Ocean University of China,Qingdao 266100;State Key Laboratory of Earth Surface Processes and Resource Ecology,Beijing Normal University,Beijing 100875)

机构地区：[1]成都信息工程大学,成都610225 [2]中国海洋大学物理海洋教育部重点实验室,青岛266100 [3]北京师范大学地表过程与资源生态国家重点实验室,北京100875

出　　处：《大气科学》2022年第1期70-82,共13页Chinese Journal of Atmospheric Sciences

基　　金：国家自然科学基金项目41975070。

摘　　要：东亚—西北太平洋地区的海平面气压直接反映了低层大气的环流特征,其动力特征对大气环流形势,气压系统的演变和天气、气候系统的发展等都有显著的影响。因此,深入分析东亚—西北太平洋地区海平面气压场的时空演变特征,对于提高我国的天气和气候预报具有重要意义。为了从非线性动力学的角度进行深入研究,文中使用了一种新方法来定量估算海平面气压吸引子的两个瞬时指标:瞬时维度和瞬时稳定度。瞬时维度表征了吸引子轨道在局部空间上的离散程度,瞬时稳定度则表征了轨道在局部时间上的稳定程度,它们共同反应了海平面气压吸引子的瞬时(逐日)动力特性。本文利用不同大小的指标值与海平面气压场的对应关系,研究了该地区海平面气压场的不同时空特征。主要结论为:(1)海平面气压吸引子的两个指标都是低值时,对应逐日环流场的空间特征表现为:气压结构单一,通常有几个强大的高低气压中心东西对峙;时间特征表现为:环流模态可以稳定的持续10 d左右。(2)当两个指标都是高值时,逐日环流场的空间特征表现为:多个弱的气压中心同时存在且结构混乱;时间特征为:环流场极不稳定,持续性仅在1 d左右。(3)瞬时维度和瞬时稳定度具有一致的年代际变化趋势:20世纪70~90年代呈现明显的下降趋势,90年代末快速上升,2000年后波动变化。The sea level pressure in the East Asia-Northwest Pacific region directly reflects the circulation characteristics of the lower atmosphere,and its dynamical characteristics have considerable effects on the atmospheric circulation situation,the evolution of the pressure system,and the development of weather and climate systems.Therefore,an indepth analysis of the spatial and temporal evolution characteristics of the sea level pressure field in the East Asia-Northwest Pacific region is of great significance to improve the weather and climate forecasting in China.To investigate the dynamical characteristics of the daily sea level pressure field from the viewpoint of nonlinear dynamics,a new method is used to quantitatively estimate two instantaneous indicators of the sea level pressure attractor:(1)The instantaneous dimension and(2)the instantaneous stability.The instantaneous dimension characterizes the dispersion of the attractor orbit in local space,and the instantaneous stability characterizes the stability of the orbit in local time,which together characterize the instantaneous(daily)dynamical properties of the sea level baroclinic attractor.This paper studies the different spatial and temporal characteristics of the sea level pressure field in the East Asia-Northwest Pacific region by the correspondence between the indicator values of different sizes and the daily sea level pressure circulation field.The main conclusions are as follows:(1)When both indicators of the sea level pressure attractor are low,the spatial characteristics of the corresponding circulation field exhibit a single pressure structure,usually with several strong highand low-pressure centers facing each other at the east-west direction,while the time characteristics show that the circulation mode can be stable for approximately 10 days.(2)Whereas,when both the indicators are high,the spatial characteristics of the circulation field show the simultaneous existence of multiple weak pressure centers with a chaotic spatial structure.As for the te

关 键 词：东亚—西北太平洋 海平面气压 瞬时维度 瞬时稳定度 大尺度环流 可预报性 

分 类 号：P434[天文地球—大气科学及气象学]