The variation in near-surface wind speed is a key dynamic parameter in the orographic effect of precipitation over eastern China.In this study,we used the latest high-resolution outputs from six GCMs in CMIP6-HighResM...The variation in near-surface wind speed is a key dynamic parameter in the orographic effect of precipitation over eastern China.In this study,we used the latest high-resolution outputs from six GCMs in CMIP6-HighResMIP to evaluate the performance of high-resolution models in simulating the orographic precipitation characteristics of typical mountainous areas in summer over eastern China.The orographic precipitation under warming scenarios was projected and constrained according to observational data.The results indicated that during the contemporary climate reference period(1979-2009),although the relationship between model-simulated near-surface wind speed and orographic light rain frequency was consistently stable,the sensitivity of the orographic light rain frequency to surface wind variability was generally underestimated,with a deviation approximately 24.1% lower than the observational values.The estimated orographic light rain frequency corrected based on the observed near-surface wind speed under a 1.5℃ warming scenario,was 36.1% lower than that of the contemporary period;this reduction was 8.6 times that without the wind speed constraint(4.2%).The MRI-AGCM3-2-S model,with a longer dataset,demonstrated relatively stable reductions in orographic light rain frequency under different warming scenarios(1.5℃,2℃,3℃,and 4℃)after the application of wind speed constraints.In all cases,the reductions exceeded those for the predictions made without the wind speed constraint.展开更多
The variation characteristics of acid rain and the relationship between the formation of acid rain and meteorological conditions were analyzed based on the observation data and meteorological records collected from ac...The variation characteristics of acid rain and the relationship between the formation of acid rain and meteorological conditions were analyzed based on the observation data and meteorological records collected from acid rain observation station in Dalian over 2006-2009.The results showed that Dalian was one of the regions with strong acid rain in northern China,with the frequency of 66% and pH value of 3.49.The acidity was the strongest in fall and weakest in spring;and the maximum and minimum frequencies were in summer and in winter respectively.Frequency of acid rain was inversely proportional to wind speed and concentration of inhalable particles in Dalian;acid rain occurred easily in foggy weather due to the steady stratification and abundant moisture;continuous precipitation did not mean the reduction of acidic material in the air,and the rainfall with increased acidity in the second day accounted for 42% in continuous precipitation cases.展开更多
The acid rain observation network of China Meteorological Administration was established in 1989 with 22 stations.From 1993 to 2005,more than 80 stations were included and maintained in the network.In 2006-2007,the nu...The acid rain observation network of China Meteorological Administration was established in 1989 with 22 stations.From 1993 to 2005,more than 80 stations were included and maintained in the network.In 2006-2007,the number of stations in the network went up to 294.In consideration of the data continuity,data used in this paper are the 14-yr observations of the 80 stations from 1993 to 2006.Based on the 14-yr observation of acid rain,analysis shows that the acid rain in China dominates in the vast regions south of the Yangtze River.Limited presence of acid rain is observed in the northern part of China.The 14-yr acid rain data reveal an expanding tendency for acid rain area,with the north of China being a growing zone,and the South China remaining virtually unchanged.The most severely polluted zone of acid rain gradually moves from Southwest China to Central China and the middle part of South China.With regard to the acid intensity of rain,the period of 1993-1998 bears the highest acid intensity;the period of 1999-2002 shows a bit weakening intensity;and in the period of 2003-2006,the acid intensity of rain increases again,basically up to the average acidity of the period of 1993-1998 by the end of 2006.In addition,rain acidity in the north of China increases markedly.As to the causes of the acid rain situation in China,this paper examined the sulfur dioxide emissions as well as the rainwater chemicals monitoring data.展开更多
基金supported by the National Key Research and Development Program of China(Grant No.2020YFA0608201)the National Natural Science Foundation of China(Grant No.42275180)。
文摘The variation in near-surface wind speed is a key dynamic parameter in the orographic effect of precipitation over eastern China.In this study,we used the latest high-resolution outputs from six GCMs in CMIP6-HighResMIP to evaluate the performance of high-resolution models in simulating the orographic precipitation characteristics of typical mountainous areas in summer over eastern China.The orographic precipitation under warming scenarios was projected and constrained according to observational data.The results indicated that during the contemporary climate reference period(1979-2009),although the relationship between model-simulated near-surface wind speed and orographic light rain frequency was consistently stable,the sensitivity of the orographic light rain frequency to surface wind variability was generally underestimated,with a deviation approximately 24.1% lower than the observational values.The estimated orographic light rain frequency corrected based on the observed near-surface wind speed under a 1.5℃ warming scenario,was 36.1% lower than that of the contemporary period;this reduction was 8.6 times that without the wind speed constraint(4.2%).The MRI-AGCM3-2-S model,with a longer dataset,demonstrated relatively stable reductions in orographic light rain frequency under different warming scenarios(1.5℃,2℃,3℃,and 4℃)after the application of wind speed constraints.In all cases,the reductions exceeded those for the predictions made without the wind speed constraint.
基金Supported by Scientific Research Special Fund for Public Welfare Industry (Meteorology) (GYHY20080620)
文摘The variation characteristics of acid rain and the relationship between the formation of acid rain and meteorological conditions were analyzed based on the observation data and meteorological records collected from acid rain observation station in Dalian over 2006-2009.The results showed that Dalian was one of the regions with strong acid rain in northern China,with the frequency of 66% and pH value of 3.49.The acidity was the strongest in fall and weakest in spring;and the maximum and minimum frequencies were in summer and in winter respectively.Frequency of acid rain was inversely proportional to wind speed and concentration of inhalable particles in Dalian;acid rain occurred easily in foggy weather due to the steady stratification and abundant moisture;continuous precipitation did not mean the reduction of acidic material in the air,and the rainfall with increased acidity in the second day accounted for 42% in continuous precipitation cases.
基金Supported by the National Natural Science Foundation of China under Grant No. 40575058
文摘The acid rain observation network of China Meteorological Administration was established in 1989 with 22 stations.From 1993 to 2005,more than 80 stations were included and maintained in the network.In 2006-2007,the number of stations in the network went up to 294.In consideration of the data continuity,data used in this paper are the 14-yr observations of the 80 stations from 1993 to 2006.Based on the 14-yr observation of acid rain,analysis shows that the acid rain in China dominates in the vast regions south of the Yangtze River.Limited presence of acid rain is observed in the northern part of China.The 14-yr acid rain data reveal an expanding tendency for acid rain area,with the north of China being a growing zone,and the South China remaining virtually unchanged.The most severely polluted zone of acid rain gradually moves from Southwest China to Central China and the middle part of South China.With regard to the acid intensity of rain,the period of 1993-1998 bears the highest acid intensity;the period of 1999-2002 shows a bit weakening intensity;and in the period of 2003-2006,the acid intensity of rain increases again,basically up to the average acidity of the period of 1993-1998 by the end of 2006.In addition,rain acidity in the north of China increases markedly.As to the causes of the acid rain situation in China,this paper examined the sulfur dioxide emissions as well as the rainwater chemicals monitoring data.
