Adopting the Easterling-Peterson (EP) techniques and considering the reality of Chinese meteorological observations, this paper designed several tests and tested for inhomogeneities in all Chinese historical surface a...Adopting the Easterling-Peterson (EP) techniques and considering the reality of Chinese meteorological observations, this paper designed several tests and tested for inhomogeneities in all Chinese historical surface air temperature series from 1951 to 2001. The result shows that the time series have been widely impacted by inhomogeneities resulting from the relocation of stations and changes in local environment such as urbanization or some other factors. Among these factors, station relocations caused the largest magnitude of abrupt changes in the time series, and other factors also resulted in inhomogeneities to some extent. According to the amplitude of change of the difference series and the monthly distribution features of surface air temperatures, discontinuities identified by applying both the E-P technique and supported by China's station history records, or by comparison with other approaches, have been adjusted. Based on the above processing, the most significant temporal inhomogeneities were eliminated, and China's most homogeneous surface air temperature series has thus been created. Results show that the inhomogeneity testing captured well the most important change of the stations, and the adjusted dataset is more reliable than ever. This suggests that the adjusted temperature dataset has great value of decreasing the uncertaities in the study of observed climate change in China.展开更多
The PRECIS,a regional climate model system developed at the UK Met Office Hadley Cen- tre for Climate Prediction and Research,which is nested in one-way mode within the HadAM3P,a higher-resolution version of the atmos...The PRECIS,a regional climate model system developed at the UK Met Office Hadley Cen- tre for Climate Prediction and Research,which is nested in one-way mode within the HadAM3P,a higher-resolution version of the atmospheric com- ponent of the Hadley Centre climate model HadCM3,is employed to simulate the baseline (1961—1990) climate for evaluation of model’s capacity of simu- lating present climate and analyze the future climate change responses in the time-slice of 2071—2100 (2080s) under SRES B2 scenario over China relative to baseline average. It is indicated from the com- parison of the simulated baseline climate with in situ observation that PRECIS can simulate the local dis- tribution characteristics of surface air temperature over China quite well; generally speaking,the simu- lation for precipitation in the north of China and in winter is better than in the south of China and in summer,respectively; the simulation of precipitation in summer is sensitive to topography,and the simu- lated precipitation values are lower than observations over southeast coastal areas. It is shown from the analyses on the simulated climate change responses in 2080s under SRES B2 scenario relative to base- line that there would be an obvious surface air tem- perature increase in the north of China relative to that in the south of China,and especially in Northwest China and Northeast China,the amplitude ofsummer mean surface air temperature increments could reach 5℃; there would be an overall increase of the simulated precipitation in 2080s under SRES B2 scenario over most areas of China,while there would be significant precipitation decreases in South China in winter; there would be obvious precipitation decreases in Northeast China and North China in summer with high surface air temperature increase. However,it presents an obvious precipitation in- crease over the middle and lower reaches of the Yangtze River in summer.展开更多
文摘Adopting the Easterling-Peterson (EP) techniques and considering the reality of Chinese meteorological observations, this paper designed several tests and tested for inhomogeneities in all Chinese historical surface air temperature series from 1951 to 2001. The result shows that the time series have been widely impacted by inhomogeneities resulting from the relocation of stations and changes in local environment such as urbanization or some other factors. Among these factors, station relocations caused the largest magnitude of abrupt changes in the time series, and other factors also resulted in inhomogeneities to some extent. According to the amplitude of change of the difference series and the monthly distribution features of surface air temperatures, discontinuities identified by applying both the E-P technique and supported by China's station history records, or by comparison with other approaches, have been adjusted. Based on the above processing, the most significant temporal inhomogeneities were eliminated, and China's most homogeneous surface air temperature series has thus been created. Results show that the inhomogeneity testing captured well the most important change of the stations, and the adjusted dataset is more reliable than ever. This suggests that the adjusted temperature dataset has great value of decreasing the uncertaities in the study of observed climate change in China.
文摘The PRECIS,a regional climate model system developed at the UK Met Office Hadley Cen- tre for Climate Prediction and Research,which is nested in one-way mode within the HadAM3P,a higher-resolution version of the atmospheric com- ponent of the Hadley Centre climate model HadCM3,is employed to simulate the baseline (1961—1990) climate for evaluation of model’s capacity of simu- lating present climate and analyze the future climate change responses in the time-slice of 2071—2100 (2080s) under SRES B2 scenario over China relative to baseline average. It is indicated from the com- parison of the simulated baseline climate with in situ observation that PRECIS can simulate the local dis- tribution characteristics of surface air temperature over China quite well; generally speaking,the simu- lation for precipitation in the north of China and in winter is better than in the south of China and in summer,respectively; the simulation of precipitation in summer is sensitive to topography,and the simu- lated precipitation values are lower than observations over southeast coastal areas. It is shown from the analyses on the simulated climate change responses in 2080s under SRES B2 scenario relative to base- line that there would be an obvious surface air tem- perature increase in the north of China relative to that in the south of China,and especially in Northwest China and Northeast China,the amplitude ofsummer mean surface air temperature increments could reach 5℃; there would be an overall increase of the simulated precipitation in 2080s under SRES B2 scenario over most areas of China,while there would be significant precipitation decreases in South China in winter; there would be obvious precipitation decreases in Northeast China and North China in summer with high surface air temperature increase. However,it presents an obvious precipitation in- crease over the middle and lower reaches of the Yangtze River in summer.
