利用1961-2000年赣州站、南昌站的年太阳总辐射与相关气象要素资料,结合Penman公式,运用6种计算净长波辐射的方法估算了两站的年太阳总辐射;建立了估算该地区年太阳总辐射的绝对误差权重法(Method of Absolute Errors,MAE),并给...利用1961-2000年赣州站、南昌站的年太阳总辐射与相关气象要素资料,结合Penman公式,运用6种计算净长波辐射的方法估算了两站的年太阳总辐射;建立了估算该地区年太阳总辐射的绝对误差权重法(Method of Absolute Errors,MAE),并给出了适用于江西省的绝对误差权重系数,以此方法计算了江西省其他76站的年太阳总辐射;并分析了该地区年太阳总辐射的时空分布特征及其变化趋势,发现:(1)1961~2000年间,江西省大部分地区太阳总辐射在3800-4400MJ·m-2·a-1;南部偏东地区较大,且存在有一大值中心;西部地区为江西省太阳总辐射最小的地区;(2)40年间,江西省年太阳总辐射呈明显下降趋势,每10年减少143.70MJ·m-2。78站中,有63站的太阳总辐射的下降趋势通过了a=0.05的显著性检验,8站表现为上升趋势;江西省北部及南部地区太阳总辐射下降较大;中部地区下降相对较小,且在鄱阳湖东侧有一低值中心。展开更多
准确估算蒸散量并了解其时空变化有助于促进水资源的综合利用、合理配置以及管理规划。为研究云南地区蒸散量及其时空变化特征,文章选用1990年~2019年云南地区25个气象站点的逐日数据,并使用R语言包Evapotranspiration中的Penman模型、A...准确估算蒸散量并了解其时空变化有助于促进水资源的综合利用、合理配置以及管理规划。为研究云南地区蒸散量及其时空变化特征,文章选用1990年~2019年云南地区25个气象站点的逐日数据,并使用R语言包Evapotranspiration中的Penman模型、AA模型及GG模型分别计算蒸散量,由于多种因素影响会导致模型所得结果存在差值,故需要研究模型的适用性以便更好地描述区域蒸散发。研究结果表明:1) Penman模型在云南地区蒸散量估算中具有较好的适用性好;2) 云南地区蒸散量具有明显的季节性特征,蒸散量集中在夏季,春冬季节较少;3) 随着地势从北到南逐渐降低,蒸散量逐渐增加,滇西北及滇东北地区蒸散量最少,在怒江、澜沧江流域多年平均蒸散量沿河流呈条带状变化。Accurately estimating evapotranspiration and understanding its spatiotemporal variations will contribute to promoting the further comprehensive utilization, rational allocation, and management planning of water resources. To study the characteristics of evapotranspiration and its spatiotemporal variations in Yunnan, the daily data of 25 meteorological stations from 1990 to 2019 was selected, and the evapotranspiration was calculated respectively by Penman, AA and GG models in R package “Evapotranspiration”. Due to the difference in the results caused by various factors, it is necessary to study the applicability of the model to better describe regional evapotranspiration. The results show that: 1) Penman method is more applicable to estimate evapotranspiration in Yunnan. 2) The evapotranspiration has seasonal characteristics in Yunnan, with evapotranspiration being concentrated in summer and relatively lower in spring and winter. 3) With the decrease of terrain from north to south, the evapotranspiration increases gradually, and the evapotranspiration is the least in Northwest and Northeast Yunnan. In the Nujiang and Lancangjiang river basins, the average annual evapotranspiration along the rivers changes in a zonal pattern.展开更多
文摘利用1961-2000年赣州站、南昌站的年太阳总辐射与相关气象要素资料,结合Penman公式,运用6种计算净长波辐射的方法估算了两站的年太阳总辐射;建立了估算该地区年太阳总辐射的绝对误差权重法(Method of Absolute Errors,MAE),并给出了适用于江西省的绝对误差权重系数,以此方法计算了江西省其他76站的年太阳总辐射;并分析了该地区年太阳总辐射的时空分布特征及其变化趋势,发现:(1)1961~2000年间,江西省大部分地区太阳总辐射在3800-4400MJ·m-2·a-1;南部偏东地区较大,且存在有一大值中心;西部地区为江西省太阳总辐射最小的地区;(2)40年间,江西省年太阳总辐射呈明显下降趋势,每10年减少143.70MJ·m-2。78站中,有63站的太阳总辐射的下降趋势通过了a=0.05的显著性检验,8站表现为上升趋势;江西省北部及南部地区太阳总辐射下降较大;中部地区下降相对较小,且在鄱阳湖东侧有一低值中心。
文摘准确估算蒸散量并了解其时空变化有助于促进水资源的综合利用、合理配置以及管理规划。为研究云南地区蒸散量及其时空变化特征,文章选用1990年~2019年云南地区25个气象站点的逐日数据,并使用R语言包Evapotranspiration中的Penman模型、AA模型及GG模型分别计算蒸散量,由于多种因素影响会导致模型所得结果存在差值,故需要研究模型的适用性以便更好地描述区域蒸散发。研究结果表明:1) Penman模型在云南地区蒸散量估算中具有较好的适用性好;2) 云南地区蒸散量具有明显的季节性特征,蒸散量集中在夏季,春冬季节较少;3) 随着地势从北到南逐渐降低,蒸散量逐渐增加,滇西北及滇东北地区蒸散量最少,在怒江、澜沧江流域多年平均蒸散量沿河流呈条带状变化。Accurately estimating evapotranspiration and understanding its spatiotemporal variations will contribute to promoting the further comprehensive utilization, rational allocation, and management planning of water resources. To study the characteristics of evapotranspiration and its spatiotemporal variations in Yunnan, the daily data of 25 meteorological stations from 1990 to 2019 was selected, and the evapotranspiration was calculated respectively by Penman, AA and GG models in R package “Evapotranspiration”. Due to the difference in the results caused by various factors, it is necessary to study the applicability of the model to better describe regional evapotranspiration. The results show that: 1) Penman method is more applicable to estimate evapotranspiration in Yunnan. 2) The evapotranspiration has seasonal characteristics in Yunnan, with evapotranspiration being concentrated in summer and relatively lower in spring and winter. 3) With the decrease of terrain from north to south, the evapotranspiration increases gradually, and the evapotranspiration is the least in Northwest and Northeast Yunnan. In the Nujiang and Lancangjiang river basins, the average annual evapotranspiration along the rivers changes in a zonal pattern.