NAME = KODAMA, Yuji ORGANIZATION = Institute of Low Temeprature Science, Hokkaido Univ. ADDRESS = Sapporo 060-0819 COUNTRY = Japan PHONE = 11-706-5509 FAX = 11-706-5509 E-MAIL = kod@pop.lowtem.hokudai.ac.jp POSTER_ONLY = yes THEME = T1 DATE = 06-Aug-04-09:29:25 ABSID = T1KY06Aug04092925 TITLE = Wind directional dependency of surface energy fluxes over north-eastern Siberia and its implications AUTHOR_1 = Kodama, Yuji INSTITUTION_1 = Institute of Lowtemperature Science, Hokkaido University PRESENTER = AUTHOR_1 AUTHOR_2 = Sato, Norifumi INSTITUTION_2 = Institute of Lowtemperature Science, Hokkaido University AUTHOR_3 = Yabuki, Hironori INSTITUTION_3 = Institute of Observational Research for Global Change, JAMSTEC AUTHOR_4 = Ishii, Yoshiyuki INSTITUTION_4 = Institute of Lowtemperature Science, Hokkaido University AUTHOR_5 = Nomura, Mutsumi INSTITUTION_5 = Field Science Ceter for Northern Biosphere, Hokkaido University AUTHOR_6 = Ohata, Tetsuo INSTITUTION_6 = Institute of Lowtemperature Science, Hokkaido University ABSTRACT = In order to better understand the water cycle over tundra, micro-meteorlogical and hydrological observations were carried out over tundra near Tiksi, North-eastern Siberia and seasonal variations of energy budget components were estimated for two years. As an average, net radiation was partitioned for sensible heat flux 25-30%, for latent heat flux 50-55% and for soil conductive heat flux 20%. Those ratios were changed by wind direction. The southwesterly winds were warm and dry, made the sensibe heat flux small or its direction changed to ground surface, and the northeasterly winds were cold, gave the sensible heat flux to the atmosphere from the tundra surface. The southwesterly winds were associated with cyclone intrusions to this area and the northeasterly winds with anti-cyclones. More frequent intrusions of cyclones would decrease the sensible heat flux and increase the latent heat flux. A simple air temperature increase experiments using a simple heat balance model showed the sensible heat flux unchanged and the latent heat flux and conducetive heat flux in soil increased.