Based on annual mean maximum and minimum temperatures,diurnal temperature range,precipitation,sunshine,total cloud cover and water barometric pressure data in Benxi County from 1958 to 2010,using statistical analysis,...Based on annual mean maximum and minimum temperatures,diurnal temperature range,precipitation,sunshine,total cloud cover and water barometric pressure data in Benxi County from 1958 to 2010,using statistical analysis,the results show that the annual and seasonal diurnal temperature ranges present significant decreasing tendencies,and the reducing tendency is the most remarkable in winter. Autumn reducing tendency is stronger than that in spring,and it is the weakest in summer. Annual and seasonal average temperatures,average maximum and minimum temperatures all present the remarkable rising trends. Rising trend of the minimum temperature is more significant than that of the maximum temperature. The monthly mean diurnal temperature range also presents reducing tendency,and the most reducing scope appear in January and February. Annual and season diurnal temperature range changes are related to sunshine,mean minimum temperature,mean maximum temperature,precipitation,total cloud cover and water barometric pressure,but various essential factors are different in each season. Annual mean temperature,annual mean minimum temperature,annual mean maximum temperature and annual diurnal temperature range all have sudden changes,but the age is inconsistent.展开更多
[Objective]The research aimed to study influence of the 850 hPa WPSH abnormality on rainfall in Jianghuai basin in early summer.[Method]Based on NCEP/NCAR 2.5°×2.5° analysis data,by using composite anal...[Objective]The research aimed to study influence of the 850 hPa WPSH abnormality on rainfall in Jianghuai basin in early summer.[Method]Based on NCEP/NCAR 2.5°×2.5° analysis data,by using composite analysis,correlation analysis,etc.,circulation and rainfall abnormalities were analyzed.Subtropical index related to geopotential height field,zonal wind field,precipitation rate,vertical velocity field and so on.Influence of the 850 hPa WPSH abnormality in early summer on rainfall in Jianghuai basin was discussed.[Result]850 hPa WPSH abnormality in early summer had important influence on rainfall in Jianghuai basin.When WPSH area was small in early summer,and ridge point was by east and north,there was no blocking high in Sea of Okhotsk area at 500 hPa height field,and pathway of the cold air at high latitude was by north.Low-pressure disturbance in plum rain frontal zone weakened,and East Asian summer monsoon circulation strengthened.Cold air in Jianghuai basin was weak,which caused less precipitation in Jianghuai basin.When WPSH area was big in early summer,and ridge point was by west and south,it was controlled by blocking high in Sea of Okhotsk area at 500 hPa height field.Low-pressure disturbance in plum rain frontal zone strengthened,and East Asian summer monsoon circulation weakened.Cold air in Jianghuai basin was strong,which caused more precipitation in Jianghuai basin.[Conclusion]The research played indicative role in precipitation abnormality in Jianghuai basin.展开更多
文摘Based on annual mean maximum and minimum temperatures,diurnal temperature range,precipitation,sunshine,total cloud cover and water barometric pressure data in Benxi County from 1958 to 2010,using statistical analysis,the results show that the annual and seasonal diurnal temperature ranges present significant decreasing tendencies,and the reducing tendency is the most remarkable in winter. Autumn reducing tendency is stronger than that in spring,and it is the weakest in summer. Annual and seasonal average temperatures,average maximum and minimum temperatures all present the remarkable rising trends. Rising trend of the minimum temperature is more significant than that of the maximum temperature. The monthly mean diurnal temperature range also presents reducing tendency,and the most reducing scope appear in January and February. Annual and season diurnal temperature range changes are related to sunshine,mean minimum temperature,mean maximum temperature,precipitation,total cloud cover and water barometric pressure,but various essential factors are different in each season. Annual mean temperature,annual mean minimum temperature,annual mean maximum temperature and annual diurnal temperature range all have sudden changes,but the age is inconsistent.
文摘[Objective]The research aimed to study influence of the 850 hPa WPSH abnormality on rainfall in Jianghuai basin in early summer.[Method]Based on NCEP/NCAR 2.5°×2.5° analysis data,by using composite analysis,correlation analysis,etc.,circulation and rainfall abnormalities were analyzed.Subtropical index related to geopotential height field,zonal wind field,precipitation rate,vertical velocity field and so on.Influence of the 850 hPa WPSH abnormality in early summer on rainfall in Jianghuai basin was discussed.[Result]850 hPa WPSH abnormality in early summer had important influence on rainfall in Jianghuai basin.When WPSH area was small in early summer,and ridge point was by east and north,there was no blocking high in Sea of Okhotsk area at 500 hPa height field,and pathway of the cold air at high latitude was by north.Low-pressure disturbance in plum rain frontal zone weakened,and East Asian summer monsoon circulation strengthened.Cold air in Jianghuai basin was weak,which caused less precipitation in Jianghuai basin.When WPSH area was big in early summer,and ridge point was by west and south,it was controlled by blocking high in Sea of Okhotsk area at 500 hPa height field.Low-pressure disturbance in plum rain frontal zone strengthened,and East Asian summer monsoon circulation weakened.Cold air in Jianghuai basin was strong,which caused more precipitation in Jianghuai basin.[Conclusion]The research played indicative role in precipitation abnormality in Jianghuai basin.
