A Study on Long-Term Validation of Land Surface Process Parameterization in Multiple Areas( II )(1/2)

Land surface process (LSP) parameterization plays an essential role in the construction of the numerical weather model and global circulation model. However, the key issues associated with energy balance of land surface process - a one-spot or one-site measurement cannot be used to describe the characteristics of spatial distributions with complex terrain. Then, one question surfaces, how can pointwise measurements be used to describe the surface characteristics of the other non-measureable sites? Hence, this project is designed to be implemented in three years with goals to answer the said question. The long-term observations include data from our ASOS (Automated Surface Observing System) sites and HiWATER (Heihe Watershed Allied Telemetry Experimental Research) project. Both adopt Bowen ratio and Eddy covariance systems (BRS and ECS) with the doubt that energy balance cannot be closed and thus it is crucial to solve the problem of unbalance energy budget by observational networks. Based on long-term observation of large-scale areas with different natural conditions, the objectives of this project are (i) Upgrading the current equipment of our ASOS to enhance the accuracy and reliability of the measured parameters of the land surface processes, (ii) Reducing the problem of unbalance energy budget at the land-air interface, and (iii) Contributing to the improvements of parameterizing the comprehensive theory for different regions. The first-year (2015/8-2016/7) plan is currently being implemented. The equipments of our ASOS were continuously maintained and upgraded to enhance capacity of completed long-term BRS and ECS observation. The sites form an observation network system to collect parameters of land surface process from Chiayi city and Heihe watershed, and the accuracy and quality of data were assessed. In the second year, girds method proposed by Cressman will be used to estimate the parameters of land surfaceprocess. These parameters will be compared with and refined based on sub-telemetry data, and characteristics of factors in the two areas will be evaluated. In the third year, the performance of the proposed method for ungauged sites will be evaluated, and the statistical properties will be characterized. Parameters will be established to be applicable with different natural conditions, and to analyze the characteristics of factors, which affect the land surface process between two regions. The driving forces of energy balance of land surface process such as regional difference will be discussed in great detail.