Synergistic Effects of Midlatitude Atmospheric Upstream Disturbances and Oceanic Subtropical Front Intensity Variability on Western Pacific Jet Stream in Winter
Synergistic Effects of Midlatitude Atmospheric Upstream Disturbances and Oceanic Subtropical Front Intensity Variability on Western Pacific Jet Stream in Winter
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冬季中纬度大气上游扰动与海洋副热带锋强度变化对西太平洋急流的协同影响
DOI：
10.1029/2020jd032788
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发表时间：
2020-08
影响因子：
4.4
通讯作者：
Bai Haokun
中科院分区：
文献类型：
--
作者：
Chen Fei Fei;Chen Qiuyu;Hu Haibo;Fang Jiabei;Bai Haokun
冬季西太平洋急流位于东亚副热带急流和东亚极锋急流的下游。它可以受到海表温度（SST）的影响，并对北美沿岸沿着的降水有很大的影响。通过观测和模式试验研究了中纬度大气上游扰动和海洋副热带锋强度变率对冬季西风急流的协同作用。结果表明，西风急流的强度和位置是由上游扰动和副热带锋区强度变率共同存在的结构所决定的。在大气上游强扰动年，西风急流锚定在25-45°N，其强度随STFZ的增强（减弱）而增强（减弱）。而当上游扰动较弱时，STFZ的强度改变了WPJS的位置。一个加强（减弱）的STFZ使WPJS向南（北）移动。进一步的研究表明，强大气扰动诱导了一个宽而深的大气斜压异常带，使低层大气从STFZ获得斜压能量。因此，WPJS锚定在STFZ的北部。此时，加强（减弱）的STFZ只是增加（减少）了同一位置的向上斜压能量，从而增加（减少）了WPJS。然而，随着大气上游扰动的减弱，加强（减弱）的STFZ对应于上空狭窄的大气斜压异常区，从而导致上升斜压能量和WPJS向南（北）移动。
In winter, the western Pacific jet stream (WPJS) is located at the downstream of East Asian subtropical jet (EASJ) and East Asian polar front jet (EAPJ). It can be affected by sea surface temperature (SST) and has great impact on precipitation along the North American coast. Synergistic effects of midlatitude atmospheric upstream disturbances and oceanic subtropical front intensity variability on WPJS in winter are investigated in both observation and model experiments. It reveals that the strength and location of WPJS are determined by the configuration of atmospheric upstream disturbances and subtropical frontal zone (STFZ) intensity variability that exist concurrently. During the strong atmospheric upstream disturbances years, the WPJS is anchored at about 25–45°N, and its strength is enhanced (abated) by the intensified (weakened) STFZ. However, when the atmospheric upstream disturbances are weak, the intensity of STFZ changes the location of WPJS. An intensified (weakened) STFZ makes WPJS move southward (northward). Further studies show that strong atmospheric disturbances induce a wide and deep atmospheric baroclinicity anomaly zone, which makes the lower atmosphere obtain baroclinic energy from STFZ. Accordingly, the WPJS is anchored just the north of STFZ. At this time, the intensified (weakened) STFZ just increases (decreases) the upward baroclinic energy at the same position and thus the WPJS. However, with the weakened atmospheric upstream disturbances, the intensified (weakened) STFZ corresponds to an overhead narrow atmospheric baroclinicity anomaly zone, thus leading to the southward (northward) movements of upward baroclinic energy and the WPJS.
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影响因子：
4.9
作者：
Haiming Xu;Mimi Xu;S. Xie;Yuqing Wang
通讯作者：
Haiming Xu;Mimi Xu;S. Xie;Yuqing Wang
基于Liang-Kleeman信息流法和群落氛围模型的多源强迫效应分析（CAM4.0）
影响因子：
4.6
作者：
ShunYu Jiang;HaiBo Hu;Ning Zhang;LiPing Lei;HaoKun Bai
通讯作者：
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影响因子：
4.6
作者：
Haokun Bai;Haibo Hu;W. Perrie;Ning Zhang
通讯作者：
Haokun Bai;Haibo Hu;W. Perrie;Ning Zhang
影响因子：
3.1
作者：
Hock Lim;Chih-Pei Chang
通讯作者：
Hock Lim;Chih-Pei Chang
影响因子：
3.1
作者：
Wei‐Chyung Wang;J. Pinto;Y. Yung
通讯作者：
Wei‐Chyung Wang;J. Pinto;Y. Yung