2000-2016年度日模型的主要研究进展及关键问题

积雪是冰冻圈重要的组成部分，基于积雪消融量与气温之间显著的正线性关系假定建立的度日模型是模拟积雪消融量的有效工具。从经典度日模型、度日模型的改进（例如辐射数据的引入）、分布式度日模型以及遥感数据在度日模型中的应用等方面总结了2000-2016年度日模型的主要研究进展。同时，考虑到影响度日模型的关键参数和变量，系统总结了降水状态判断的温度阈值、度日因子、辐射系数的最新研究进展及其在度日模型中的使用。在变化环境下开展度日模型与遥感、GIS技术相结合的协同研究，是目前度日模型研究的主要方向。

Study of degree-day model from 2000 to 2016: the main progress and key issues

Snow cover is an important component of the cryosphere.The degree-day model based on the assumption of positive linear relationship between snow ablation and temperature is an effective tool to simulate the snow ablation.This paper summarizes the main research progress of degree-day model in following aspects:the classical degree-day model,the improvement of degree-day model,the distributed degree-day model and the application of remote sensing data in degree-day model from 2000 to 2016.Meanwhile,given the key parameters and variables,the applications and new progresses of temperature threshold of precipitation type,the degree-day factor and the radiation coefficient are summarized systematically.Collaborative research,combining with remote sensing,GIS and degree-day model,is the primary research orientation of degree-day model.