Improvements in Long-Lead Prediction of Early-Summer Subtropical Frontal Rainfall Based on Arctic Sea Ice
Improvements in Long-Lead Prediction of Early-Summer Subtropical Frontal Rainfall Based on Arctic Sea Ice
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基于北极海冰的初夏副热带锋面降雨长提前预报的改进
DOI：
10.1007/s11802-019-3875-9
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发表时间：
2019-06
影响因子：
1.6
通讯作者：
Huang Fei
中科院分区：
文献类型：
--
作者：
Xing Wen;Huang Fei
东亚(EA)夏季降水的季节预报，特别是提前时间较长的夏季降水，需求很大，但仍然非常具有挑战性。本研究旨在通过考虑北冰洋海冰(ASI)变率作为新的潜在预报因子，对初夏(5-6月平均，MJ)的副热带锋面降水(SFR)进行长期预报。定义了应用于EA上MJ降水异常的经验正交函数(EOF)分析的主成分MJ SFR指数(SFRI)。对38年观测(1979-2016)的分析揭示了三个物理上的结果预测因素。在SFRI增强之前，前一个秋季的ASI偶极距平，欧亚大陆的海平面气压(SLP)偶极子，以及前一个冬季热带太平洋的海表面温度异常三极型。这些前兆预示着鄂霍次克高压增强，局地偏低，西太平洋副热带高压增强。这些因素控制着正SFRI的环流特征。结合这三个预测因子，建立了预测SFRI的物理-经验模型。对1979-2016年期间进行了后向预测，结果显示，后向预测技能出人意料地大大高于一个四动力模型对1979-2010年期间的整体预测(0.72比0.47)。请注意，与来自热带到中纬度的信号相比，ASI变化是一个新的预报因子。在不包含ASI信号的情况下，长超前后播技术显著较低，这意味着ASI变化在MJ EA降水的长超前季节预报方面具有很高的实用价值。
Seasonal prediction of East Asia (EA) summer rainfall, especially with a longer-lead time, is in great demand, but still very challenging. The present study aims to make long-lead prediction of EA subtropical frontal rainfall (SFR) during early summer (May–June mean, MJ) by considering Arctic sea ice (ASI) variability as a new potential predictor. A MJ SFR index (SFRI), the leading principle component of the empirical orthogonal function (EOF) analysis applied to the MJ precipitation anomaly over EA, is defined as the predictand. Analysis of 38-year observations (1979–2016) revealed three physically consequential predictors. A stronger SFRI is preceded by dipolar ASI anomaly in the previous autumn, a sea level pressure (SLP) dipole in the Eurasian continent, and a sea surface temperature anomaly tripole pattern in the tropical Pacific in the previous winter. These precursors foreshadow an enhanced Okhotsk High, lower local SLP over EA, and a strengthened western Pacific subtropical high. These factors are controlling circulation features for a positive SFRI. A physical-empirical model was established to predict SFRI by combining the three predictors. Hindcasting was performed for the 1979–2016 period, which showed a hindcast prediction skill that was, unexpectedly, substantially higher than that of a four-dynamical models' ensemble prediction for the 1979–2010 period (0.72versus0.47). Note that ASI variation is a new predictor compared with signals originating from the tropics to mid-latitudes. The long-lead hindcast skill was notably lower without the ASI signals included, implying the high practical value of ASI variation in terms of long-lead seasonal prediction of MJ EA rainfall.
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影响因子：
5.2
作者：
Li, JP;Wang, JLXL
通讯作者：
Wang, JLXL
东亚夏初和夏末降雨异常的不同主要模式
影响因子：
4.9
作者：
Liu, Jian;Wang, Bin;Yang, Jing;Wu, Zhiwei;Zhou, Tianjun
通讯作者：
Zhou, Tianjun
DOI：
10.1002/2016jd025856
发表时间：
2017-02
期刊：
Journal of Geophysical Research: Atmospheres
影响因子：
--
作者：
W. Xing;Bin Wang;S. Yim;K. Ha
通讯作者：
W. Xing;Bin Wang;S. Yim;K. Ha
影响因子：
4.6
作者：
S. Yim;Bin Wang;W. Xing
通讯作者：
S. Yim;Bin Wang;W. Xing
DOI：
10.5065/d6r78c9s
发表时间：
2015-12
期刊：
--
影响因子：
--
作者：
G. Huffman;D. Bolvin;E. Nelkin;R. Adler
通讯作者：
G. Huffman;D. Bolvin;E. Nelkin;R. Adler