Summer Water Vapor Sources in Northeast Asia and East Siberia Revealed by a Moisture-Tracing Atmospheric Model

• Previous studies found a seesaw pattern of summer precipitation between northeast Asia and east Siberiaon an interannual time scale, which is associated with an eastward-propagating atmospheric wave train overEurasia and corresponding water vapor transport circulations. Using a general circulation model with anembedded water-tagging module, the main water vapor sources of the two regions, as well as the relativecontributions of each source region to the total precipitation for both the climatological mean and interdecadalvariation, are further compared in this study. The model simulation results show that local evaporation,the Pacific Ocean, and East Asia are the dominant moisture sources for northeast Asian precipitation.In contrast, for east Siberia, moisture mainly originates from the Pacific Ocean, northeast Asia, west Siberia,and local evaporation. This suggests that the local evaporation and Pacific Ocean are both crucial to themoisture supply of the two regions, implying the important roles of the land processes and adjacent oceanicsources. In addition, northeast Asia appears to be the major moisture source for east Siberia, whereas eastSiberia has weak impacts on the moisture input for northeast Asia. Further analysis finds that the modelsimulation can capture interdecadal changes in summer precipitation over the two regions around the late1990s. This interdecadal change is mainly manifested in the moisture supplies from the Pacific Ocean, NorthAtlantic Ocean, and east Siberia, which suggests a link with the circulation anomalies under the combinedimpacts of the Pacific decadal oscillation and the Atlantic multidecadal oscillation.

Subject headings

NATURVETENSKAP  -- Geovetenskap och miljövetenskap (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences (hsv//eng)

Publication and Content Type

ref (subject category)

art (subject category)