为了解FY-4A卫星云顶高度(cloud top height,CTH)产品对陕南暖季降水云的反映状况,以陕南地区2020年暖季(5-10月)降水过程为例,对比分析FY-4A卫星CTH产品与汉中天气雷达回波顶高(echo top height,ET)产品对该地区降水云的探测资料。结...为了解FY-4A卫星云顶高度(cloud top height,CTH)产品对陕南暖季降水云的反映状况,以陕南地区2020年暖季(5-10月)降水过程为例,对比分析FY-4A卫星CTH产品与汉中天气雷达回波顶高(echo top height,ET)产品对该地区降水云的探测资料。结果表明:(1)在暖季21次降水过程中,卫星产品的云顶高度揭示了陕南地区降水云的空间变化,尤其在大巴山峡口附近,CTH值显著偏高的区域与陕南强降水的多发区相吻合。(2)以2020年暖季一次强降水过程为例,云顶高度探测表明卫星CTH的高值区通常与雷达ET的高值区相对应,说明卫星能够揭示陕南山区降水云体的时空变化,但在雷达ET高值区卫星CTH存在以填充值代替的现象,说明复杂地形区CTH填充值可能是潜在强降水区。(3)对比两种探测在降水云体发展中差异,结果显示在降水云初生和消亡阶段,两者绝对差值小于2 km的格点数与总格点数的占比都超过50%,说明CTH产品能有效捕捉降水云的初生和消亡变化。在降水云成熟阶段,两者平均差值超过4 km,卫星探测云体不确定性增加,较难反映降水云体特征。展开更多
Satellite remote sensing is essential for solar energy meteorology.The 14-channel Advanced Geostationary Radiation Imager of the Fengyun-4 series of satellites performs a full-disc scan over greater China every 15 min...Satellite remote sensing is essential for solar energy meteorology.The 14-channel Advanced Geostationary Radiation Imager of the Fengyun-4 series of satellites performs a full-disc scan over greater China every 15 min,providing highgranularity information that allows the retrieval of cloud properties,aerosol optical depth,and precipitable water vapor content,which can facilitate the acquisition of surface solar irradiance components through physical methods.Machinelearning methods have also shown potential in providing accurate end-to-end surface solar radiation retrievals.Albeit the physical principles of irradiance retrieval and machine-learning algorithms are fairly well known,the public service concerning disseminating the irradiance product to the energy and power industry still lacks robustness and consistency.In this perspective article,the status quo of Fengyun-4 irradiance products is first reviewed.Then,from the perspective of solar resource assessment and forecasting,three fundamental characteristics of the kind of irradiance products that are most serviceable to the solar energy sector are identified,namely,coverage,timeliness,and accessibility.Finally,an outlook on the new-generation Fengyun radiation service is put forward,and the prospective scientific and practical challenges are elaborated.展开更多
文摘为了解FY-4A卫星云顶高度(cloud top height,CTH)产品对陕南暖季降水云的反映状况,以陕南地区2020年暖季(5-10月)降水过程为例,对比分析FY-4A卫星CTH产品与汉中天气雷达回波顶高(echo top height,ET)产品对该地区降水云的探测资料。结果表明:(1)在暖季21次降水过程中,卫星产品的云顶高度揭示了陕南地区降水云的空间变化,尤其在大巴山峡口附近,CTH值显著偏高的区域与陕南强降水的多发区相吻合。(2)以2020年暖季一次强降水过程为例,云顶高度探测表明卫星CTH的高值区通常与雷达ET的高值区相对应,说明卫星能够揭示陕南山区降水云体的时空变化,但在雷达ET高值区卫星CTH存在以填充值代替的现象,说明复杂地形区CTH填充值可能是潜在强降水区。(3)对比两种探测在降水云体发展中差异,结果显示在降水云初生和消亡阶段,两者绝对差值小于2 km的格点数与总格点数的占比都超过50%,说明CTH产品能有效捕捉降水云的初生和消亡变化。在降水云成熟阶段,两者平均差值超过4 km,卫星探测云体不确定性增加,较难反映降水云体特征。
基金supported by the National Natural Science Foundation of China(project no.42375192)。
文摘Satellite remote sensing is essential for solar energy meteorology.The 14-channel Advanced Geostationary Radiation Imager of the Fengyun-4 series of satellites performs a full-disc scan over greater China every 15 min,providing highgranularity information that allows the retrieval of cloud properties,aerosol optical depth,and precipitable water vapor content,which can facilitate the acquisition of surface solar irradiance components through physical methods.Machinelearning methods have also shown potential in providing accurate end-to-end surface solar radiation retrievals.Albeit the physical principles of irradiance retrieval and machine-learning algorithms are fairly well known,the public service concerning disseminating the irradiance product to the energy and power industry still lacks robustness and consistency.In this perspective article,the status quo of Fengyun-4 irradiance products is first reviewed.Then,from the perspective of solar resource assessment and forecasting,three fundamental characteristics of the kind of irradiance products that are most serviceable to the solar energy sector are identified,namely,coverage,timeliness,and accessibility.Finally,an outlook on the new-generation Fengyun radiation service is put forward,and the prospective scientific and practical challenges are elaborated.
