Historical trends in the jet streams
Historical trends in the jet streams
复制标题
DOI：
10.1029/2008gl033614
复制
发表时间：
2008-04-18
影响因子：
5.2
通讯作者：
Caldeira, Ken
中科院分区：
文献类型：
--
作者：
Archer, Cristina L.;Caldeira, Ken
急流是位于对流层顶附近的蜿蜒的快风带，是中纬度天气的驱动因素。这是第一个研究的基础上，ERA-40和NCEP/NCAR再分析数据集1979年至2001年的急流属性的历史趋势进行分析。我们定义急流属性的基础上的质量和质量通量加权平均值。我们发现，总的来说，急流在两个半球的高度上升，并向极地移动。在北方，急流减弱。在南半球，副热带急流减弱，而极地急流加强。在当地和季节性地发现了这种普遍行为。需要进一步的观测和分析，才能有把握地将这些变化的原因归因于人为气候变化、自然变率或两者的某种组合。
Jet streams, the meandering bands of fast winds located near the tropopause, are driving factors for weather in the midlatitudes. This is the first study to analyze historical trends of jet stream properties based on the ERA-40 and the NCEP/NCAR reanalysis datasets for the period 1979 to 2001. We defined jet stream properties based on mass and mass-flux weighted averages. We found that, in general, the jet streams have risen in altitude and moved poleward in both hemispheres. In the northern hemisphere, the jet stream weakened. In the southern hemisphere, the sub-tropical jet weakened, whereas the polar jet strengthened. Exceptions to this general behavior were found locally and seasonally. Further observations and analysis are needed to confidently attribute the causes of these changes to anthropogenic climate change, natural variability, or some combination of the two.