Abstract:Driven by the reanalysis data with 2.5°×2.5° spatial resolution, the HYSPLIT v4.9 trajectory tracking mode was used to conduct the tracking simulations in 308 cases of cold eddy rainfall in northeast China. Results showed that water vapor for the northeast China cold eddy rain storm comes from four sources: (a) the Eurasian continent, especially areas near Baikal Lake; (b) Okhotsk Sea, Sea of Japan, the Yellow Sea, Bohai Sea and the western Pacific; (c) sea area from Bengal Bay to the South China Sea; (d) the northeast China. The western Pacific and its nearby sea areas contribute to the largest water vapor, amountuing to 39.8%, including the Okhotsk Sea, Sea of Japan, the Yellow Sea, Bohai Sea and the East China Sea; water vapor contribution rate for the sea area covered from Bengal Bay to the South China Sea is followed with 32.1%; water vapor contribution rate in Eurasia continent and Northeast China are 20.9% and 7.2%, respectively; Eurasia continent mainly transported the dry and cold air mass at 700 hPa, while the other sea areas transported the warm and moist air mass below 800 hPa.