天空河流:发现、概念及其科学问题

Sky River: Discovery, concept, and implications for future research

介绍了天空河流的发现、概念及未来研究.对气象再分析数据的分析发现,大气水汽通量场中不仅存在通量强度相对周围区域更大的局部性条带结构,而且整个水汽通量场中都存在着通量相对较高的水汽输送网络结构,形成了全球及区域水汽输送的主干通道.由于这些通量强度很高的条带构成的网络结构是水汽汇聚、输送最为集中、强度最大的网络,与地表河流具有类似的分级属性,我们可将这种水汽输送的网络结构上称为'天空河流(River in the Sky)',或简称'天河(Sky River)'.天河是对水汽集中输送带概念的升华和深化,新的概念的提出有利于我们认识大气中的水汽输运规律,对研究地球水循环长期演化规律的统计特征及其与地表水文、泥沙等流域过程的相互作用机制具有重要的价值.

Presented in this paper is a brief introduction to our recent discovery and definition of Sky River, as well as its implications for future research. Based on meteorological reanalysis data, we found that there exist highly structured water vapor conveyance systems in the troposphere of the atmosphere. The water vapor conveyance systems have higher vertically integrated flux than their immediate environments, consisting the dominant channels from local scale to global scale for atmospheric water vapor transfer. The water vapor transfer systems in the troposphere share the similarity of having high water（vapor） conveyance with land surface rivers and thus can be referred to as ＂River in the Sky＂, or simply ＂Sky River＂. Sky River is different from ＂atmospheric river＂ essentially in that it is a global system where water vapor concentrated and conveyed by atmospheric circulations, rather than the transient and local high flux belts found in previous studies. Studies on the Sky Rivers will help us to have a new vision about global atmospheric water vapor transfer and a better understanding of global water cycle.