[M-IS01] Environmental, socio-economic, and climatic changes in Northern Eurasia

[MIS01-07] Quantification of the water vapor transport between the northern Eurasia and Arctic ocean considering the water vapor origin

*Tomonori Sato¹、Tetsu Nakamura¹、Yoshihiro Iijima²、Tetsuya Hiyama³ (1.Hokkaido University、2.Mie University、3.Nagoya University)

キーワード：Atmospheric water vapor, Water vapor transport model, Arctic

Arctic warming has been a pronounced feature of the recent climate change. Related changes in meridional thermal gradient and surface evaporation from the Arctic ocean could modulate the horizontal water vapor transport which may further affect the continental precipitation variability. The study develops the atmospheric water vapor transport model in which the spatiotemporal variation of water vapor fraction originated from the evaporation at the designated land and ocean surface areas is predicted. The model experiment driven by JRA-55 reanalysis dataset with bias correction reveals that the water vapor originated from the Arctic ocean can be transported southward, penetrating the northern coastal regions of the Eurasian continent. The monthly mean fraction of Arctic-originated water vapor relative to total precipitable water vapor becomes as high as 20% in northern Eurasia. The higher fraction of Arctic water vapor is partly attributable to the enhanced evaporation from the Arctic ocean in the low sea ice years. Besides that, the atmospheric circulation pattern is found to be an important factor for the high fraction because the high Arctic fraction is likely to occur in the area where monthly mean southward moisture flux is strong, like western Siberia in September 2017 and eastern Siberia in September 2011.