[Objective] The study aimed to analyze the changing characteristics of evaporation in Cangzhou City in recent 40 years.[Method] Based the observation data of evaporation measured by small evaporation pans （with the c...[Objective] The study aimed to analyze the changing characteristics of evaporation in Cangzhou City in recent 40 years.[Method] Based the observation data of evaporation measured by small evaporation pans （with the caliber of 20 cm） from weather stations of Cangzhou dur- ing 1971 -2010, the monthly, seasonal, annual and decadal variation of evaporation were analyzed using conventional assessment methods. [Result] During 1971 -2010, monthly average evaporation in Cangzhou fluctuated within a year, and the maximum value appeared in June, while the minimum value appeared in January. Within a year, average evaporation was the highest in summer, and its variation was the greatest; it was the lowest and varied most slightly in winter. During 1971 -2010, evaporation in winter showed an increasing trend, while evaporation showed a de- creasing trend in spring and autumn, and there was no obvious change in evaporation in summer. Annual average evaporation in Cangzhou showed a decreasing trend from 1971 to 2010, and the highest evaporation reached 2 273.3 ram, appearing in 1972. The lowest evaporation was only 1 681.4 mm, appearing in 1990, and the difference between them reached 591.9 mm. Average evaporation in each decade showed a decrease trend, and the maximum value appeared in the 1980s （1 958.6 mm）, while the minimum value appeared in the first ten years of the 21st century （1 880.9 mm）. [ Conclusion] The research could provide theoretical references for studies on climate change in Cangzhou in future.展开更多
[Objectivel The aim was to study climate change trend in Cangzhou City in recent 38 years. [ Method] Based on the climate date such as temperature, precipitation, sunshine, temperature, relative humidity, pressure, th...[Objectivel The aim was to study climate change trend in Cangzhou City in recent 38 years. [ Method] Based on the climate date such as temperature, precipitation, sunshine, temperature, relative humidity, pressure, the climate change trend in Cangzhou in recent 38 years was studied by statistical analysis methods like trend image and climate tendency rate. [ Result] The annual mean temperature, annual mean maximum and minimum temperature in Cangzhou in recent 38 years were increasing and the minimum temperature rose most quickly. The annual mean pre- cipitation decreased at a rate of 45.804 mm/10 a. The annual mean sunshine hours reduced at a rate of 104.2 h/10 a. The annual mean cloud amount reduced at a rate of 0.355%/10 a. The temperature rose at 0, 10, 15 and 20 cm, but the temperature decreased at 5 cm. Annual mean rel- ative humidity decreased. Annual mean air pressure, mean maximum and minimum air pressure reduced and the annual mean lowest air pressure reduced most distinctly. [ Conclusionl The study provided theoretical basis for the climate change in Cangzhou under global warming background.展开更多
文摘[Objective] The study aimed to analyze the changing characteristics of evaporation in Cangzhou City in recent 40 years.[Method] Based the observation data of evaporation measured by small evaporation pans （with the caliber of 20 cm） from weather stations of Cangzhou dur- ing 1971 -2010, the monthly, seasonal, annual and decadal variation of evaporation were analyzed using conventional assessment methods. [Result] During 1971 -2010, monthly average evaporation in Cangzhou fluctuated within a year, and the maximum value appeared in June, while the minimum value appeared in January. Within a year, average evaporation was the highest in summer, and its variation was the greatest; it was the lowest and varied most slightly in winter. During 1971 -2010, evaporation in winter showed an increasing trend, while evaporation showed a de- creasing trend in spring and autumn, and there was no obvious change in evaporation in summer. Annual average evaporation in Cangzhou showed a decreasing trend from 1971 to 2010, and the highest evaporation reached 2 273.3 ram, appearing in 1972. The lowest evaporation was only 1 681.4 mm, appearing in 1990, and the difference between them reached 591.9 mm. Average evaporation in each decade showed a decrease trend, and the maximum value appeared in the 1980s （1 958.6 mm）, while the minimum value appeared in the first ten years of the 21st century （1 880.9 mm）. [ Conclusion] The research could provide theoretical references for studies on climate change in Cangzhou in future.
文摘[Objectivel The aim was to study climate change trend in Cangzhou City in recent 38 years. [ Method] Based on the climate date such as temperature, precipitation, sunshine, temperature, relative humidity, pressure, the climate change trend in Cangzhou in recent 38 years was studied by statistical analysis methods like trend image and climate tendency rate. [ Result] The annual mean temperature, annual mean maximum and minimum temperature in Cangzhou in recent 38 years were increasing and the minimum temperature rose most quickly. The annual mean pre- cipitation decreased at a rate of 45.804 mm/10 a. The annual mean sunshine hours reduced at a rate of 104.2 h/10 a. The annual mean cloud amount reduced at a rate of 0.355%/10 a. The temperature rose at 0, 10, 15 and 20 cm, but the temperature decreased at 5 cm. Annual mean rel- ative humidity decreased. Annual mean air pressure, mean maximum and minimum air pressure reduced and the annual mean lowest air pressure reduced most distinctly. [ Conclusionl The study provided theoretical basis for the climate change in Cangzhou under global warming background.
