The study on applications of Large Aperture Scintillometer measuring large scale flux

As a new flux measuring instrument, Large Aperture Scintillometer (LAS) developed rapidly in recent years, which can measure sensible heat flux in large scales, from several hundred meters to several kilometers even to ten kilometers, In other words, LAS can match well with remote sensing scale. There were erected two LAS equipments in the A\´rou freeze/thawing observation station (upper reaches) and Linze grassland station (middle reaches), which distributed in the upper and middle reaches of Heihe river basin supported by "Watershed Airborne Telemetry Experimental Research (WATER)". This paper focused on the daily variation and seasonal variation characteristics of sensible heat flux at A\´rou and Linze, and compared the sensible heat flux observed by LAS and EC. The Source area (Footprint) of the two stations is calculated by analysis model according to the LAS and EC data. The results showed that: sensible heat flux variations observed by LAS and EC have a good correspondence. Some time interval exists more distinct difference which is caused by the different underlying surfaces. Most of the time, sensible heat flux observed by LAS is greater than that of EC, and that is because the source area of LAS is far more larger than that of EC. LAS has an original function of area-averaged.