Water Recycling between the Land Surface and Atmosphere on the Northern Tibetan Plateau—A Case Study at Flat Observation Sites

Abstract

ABSTRACT High-resolution soil moisture, temperature, and precipitation data from the northern part of the Tibetan Plateau provide the basis for analyzing the cycling of water between the land surface and atmosphere. Data analyzed come from the Intensive Observation Period (IOP) of the GEWEX (Global Energy and Water Cycle Experiment) Asian Monsoon Experiment (GAME) on the Tibetan Plateau (GAME-Tibet). Observations from July to August 1998 show that evaporation from flat land surfaces was 177 mm on the south side of the Tanggula Mountains, and 73 mm on the north side. These represent about 73% and 58%, respectively, of the precipitation in the same period. Evaporation not only transports considerable water but also considerable energy from the land surface to the atmosphere, which can slow the rising of soil temperatures. Differences in the evaporation between the south and north sides of Tanggula Mountains is mainly caused by differences in precipitation.