Large-scale and synoptic meteorology in the south-east Pacific during the observations campaign VOCALS-REx in austral Spring 2008
Large-scale and synoptic meteorology in the south-east Pacific during the observations campaign VOCALS-REx in austral Spring 2008
复制标题
DOI：
10.5194/acp-11-4977-2011
复制
发表时间：
2011-05
影响因子：
6.3
通讯作者：
T. Toniazzo;S. Abel;R. Wood;C. Mechoso;G. Allen;L. Shaffrey
中科院分区：
文献类型：
--
作者：
T. Toniazzo;S. Abel;R. Wood;C. Mechoso;G. Allen;L. Shaffrey
抽象。我们提出了一个描述性的概述，在东南副热带太平洋（SEP）在VOCALS-REx密集观测活动，这是2008年10月至11月之间进行的。主要基于业务分析，预报，再分析和卫星观测的数据，我们专注于从天气到行星的时空尺度。一个气候背景下，在运动期间观察到的具体条件放置，特别是大尺度和区域环流之间的关系。文中还讨论了与日微风系统有关的平均环流。然后，我们提供了一个总结的一天到一天的天气尺度环流，空气粒子轨迹，并在SEP云量在VOCALS-REx。确定了三个气象学上不同的时间段，并讨论了其不同性质的大规模原因。第一个时期的特点是显着的变化与天气尺度系统感兴趣的SEP，而随后的两个阶段受到行星尺度的扰动与较慢的演变。初期和后期之间的变化可以部分地解释从定期的三月的年周期，但从亚季节的变化和遥相关的贡献是重要的。在整个两个月的研究中，我们发现逆温覆盖的海洋边界层（MBL）的深度和研究区域的低云量之间存在显着的相关性。我们讨论了这种相关性，并认为，至少作为一个粗略的近似一个典型的缩放可以应用相关的MBL和云的特性与大尺度参数的SST和对流层温度。这些结果与以前发现的经验关系，涉及低对流层稳定性是一致的。
Abstract. We present a descriptive overview of the meteorology in the south eastern subtropical Pacific (SEP) during the VOCALS-REx intensive observations campaign which was carried out between October and November 2008. Mainly based on data from operational analyses, forecasts, reanalysis, and satellite observations, we focus on spatio-temporal scales from synoptic to planetary. A climatological context is given within which the specific conditions observed during the campaign are placed, with particular reference to the relationships between the large-scale and the regional circulations. The mean circulations associated with the diurnal breeze systems are also discussed. We then provide a summary of the day-to-day synoptic-scale circulation, air-parcel trajectories, and cloud cover in the SEP during VOCALS-REx. Three meteorologically distinct periods of time are identified and the large-scale causes for their different character are discussed. The first period was characterised by significant variability associated with synoptic-scale systems interesting the SEP; while the two subsequent phases were affected by planetary-scale disturbances with a slower evolution. The changes between initial and later periods can be partly explained from the regular march of the annual cycle, but contributions from subseasonal variability and its teleconnections were important. Across the whole of the two months under consideration we find a significant correlation between the depth of the inversion-capped marine boundary layer (MBL) and the amount of low cloud in the area of study. We discuss this correlation and argue that at least as a crude approximation a typical scaling may be applied relating MBL and cloud properties with the large-scale parameters of SSTs and tropospheric temperatures. These results are consistent with previously found empirical relationships involving lower-tropospheric stability.