Tian-Xiang Yue(岳天祥), Na Zhao(赵娜), R. Douglas Ramsey, Chen-liang Wang, Ze-Meng Fan, Chuan-Fa Chen, Yi-Min Lu and Bai-Lian Li. 2013. Climate change trend in China, with improved accuracy. Climatic Change 120:137-151. 

中国气候变化趋势的高精度模拟 

 摘要 

        研究表明，每一个栅格处的气候要素值可表达为该栅格的气候要素趋势面与其残差之和。年平均气温与其影响因素之间的关系是空间平稳的，其趋势面可采用普通最小二乘回归（OLS）的全局关系描述；而年均降水量随地形变化呈现很大的空间变异性，年均降水量是空间非平稳气候要素，因此需用地理加权回归（GWR）来估计其趋势面。对年平均气温，首先采用普通最小二乘回归得到年平均气温与纬度、高程之间的统计关系式（趋势面），继而对趋势面残差采用高精度曲面建模（HASM）进行迭代修正，此模拟方法名称缩写为HASM-OLS。对年均降水量，先对气象台站观测值进行BOX-COX 变换，然后对变换后的年平均降水量采用地理加权回归得到年平均降水量与经度、纬度、高程、坡向因子及地形开阔度间的统计关系（趋势面），此趋势面值与HASM残差曲面之和即为每个栅格处的年平均降水量值，年平均降水量的此模拟方法名称缩写为HASM-GWR-BC。结果表明，自上世纪60年代以来，年平均气温具有增加趋势，特别是80年代之后，年平均气温升高呈增速趋势。总体上，自上世纪6 0年代以来，年平均气温增加了1.44℃；除了青海、西藏地区外，全国增温率由南向北逐渐增加。例如，在黑龙江省，≥10℃年积温的2100oC.d等值线自60年代以来向西北方向偏移了255km；≥10℃年积温的2400oC.d等值线向北移动了167km。自二十世纪6 0年代以来，年均降水量在青海、西藏及干旱地区有持续的增加趋势。平均而言，二十世纪60年代至90年代之间，中国气候有暖湿趋势；而从二十世纪90年代到二十一世纪10年代，气候有暖干趋势。自60年代以来，相比中国南部地区，青海、西藏及中国北部地区经历了更多的极端气候事件。 

Climate change trend in China, with improved accuracy                        

Tian-Xiang Yue, Na Zhao, R. Douglas Ramsey, Chen-Liang Wang, Ze-Meng Fan,  

Chuan-Fa Chen, Yi-Min Lu and Bai-Lian Li. 

 Abstract :  We have found that a spatial interpolation of mean annual temperature (MAT) in China can be accomplished using a global ordinary least squares regression model since the relationship between temperature and its environmental determinants is constant. Therefore the estimation of MAT does not very across space and thus exhibits spatial stationarity. The interpolation of mean annual precipitation (MAP), however, is more complex and changes spatially as a function of topographic variation. Therefore, MAP shows spatial non-stationarity and must be estimated with a geographically weighted regression. A statistical transfer function (STF) of MAT was formulated using minimized residuals output from a high accuracy and high speed method for surface modeling (HASM) with an ordinary least squares (OLS) linear equation that uses latitude and elevation as independent variables, abbreviated as HASM - OLS. The STF of MAP under a BOX-COX transformation is derived as a combination of minimized residuals output by HASM with a geographically weighted regression (GWR) using latitude, longitude, elevation, impact coefficient of aspect and sky view factor as independent variables, abbreviated as HASM-GWR-BC. In terms of HASM-OLS and HASM-GWR-BC, MAT had an increasing trend since the 1960s in China, with an especially accelerated increasing trend since 1980. Overall, our data show that MAT has increased by 1.44 °C since the 1960s. The warming rates increase from the south to north in China, except in the Qinghai-Xizang plateau. Specifically, the 2,100 °C·d contour line of annual accumulated temperature (AAT) of ≥10 °C shifted northwestward 255 km in the Heilongjiang province since the 1960s. MAP in Qinghai-Xizang plateau and in arid region had a continuously increasing trend. In the other 7 regions of China, MAP shows both increasing and decreasing trends. On average, China became wetter from the 1960s to the 1990s, but drier from the 1990s to 2000s. The Qinghai-Xizang Plateau and Northern China experienced more climatic extremes than Southern China since the 1960s.