Linking Northern Hemisphere temperature extremes to Rossby wave packets
Linking Northern Hemisphere temperature extremes to Rossby wave packets
复制标题
DOI：
10.1002/qj.3228
复制
发表时间：
2018-01-01
影响因子：
8.9
通讯作者：
Fink, A. H.
中科院分区：
文献类型：
--
作者：
Fragkoulidis, G.;Wirth, V.;Fink, A. H.
这项工作研究了 1979 年至 2015 年期间北半球对流层上层瞬态罗斯贝波包 (RWP) 与对流层下层极端温度之间的统计联系。 ERA-中期再分析的数据用于诊断 RWP 振幅和温度异常以及对其关联进行系统检查。研究发现，RWP 振幅较大的区域与中纬度地区许多地区出现低对流层极端温度的可能性增加有关。尽管季节和区域间的变化是明显的，但这种联系总是比使用基于傅立叶波数振幅的环球波纹度度量的分析更强。通过对欧洲最近两次最严重的热浪（即欧洲最近两次最严重的热浪）的调查来补充气候学结果，获得了进一步的见解。 2003年和2010年夏天。研究发现，这两个事件都与明显的非环全球 RWP 相关，但两个事件之间的差异表明，RWP 和极端温度之间的联系机制取决于具体情况。上述结果强调了对流层上层动力学的重要作用，并为未来在天气和气候时间尺度上研究热浪和寒潮开辟了途径。
This work investigates the statistical linkage between upper-tropospheric transient Rossby wave packets (RWPs) and lower-tropospheric temperature extremes in the Northern Hemisphere during the period 1979-2015. Data from ERA-Interim reanalyses are used for the diagnosis of RWP amplitude and temperature anomalies as well as the systematic examination of their connection. Areas of large RWP amplitude are found to be associated with an increased probability of lower-tropospheric temperature extremes in many regions of the midlatitudes. Although a seasonal and inter-regional variability is apparent, this link is always stronger than in an analysis using a circumglobal waviness metric based on Fourier wavenumber amplitudes. Further insight is gained by complementing the climatological results with an investigation of the two most severe recent heat waves in Europe, viz. during the 2003 and 2010 summers. Both events are found to be associated with conspicuous non-circumglobal RWPs, but differences between the two events suggest that the mechanisms linking RWPs and temperature extremes are case-dependent. The aforementioned results underscore the important role of upper-troposphere dynamics and open up avenues for future research on heat waves and cold spells at both weather and climate time-scales.