回顾了中国气象局高分辨率陆面数据同化系统(High Resolution China Meteorological Administration Land Data Assimilation System,HRCLDAS)的研发历程,重点介绍了HRCLDAS研发过程中的重要进展和突破,概要阐述了这些进展对HRCLDAS业...回顾了中国气象局高分辨率陆面数据同化系统(High Resolution China Meteorological Administration Land Data Assimilation System,HRCLDAS)的研发历程,重点介绍了HRCLDAS研发过程中的重要进展和突破,概要阐述了这些进展对HRCLDAS业务化的贡献。主要包括:引入1 km分辨率地形数据,采用多重网格变分分析技术制作1 km分辨率气象驱动数据;基于FY-2卫星1 km可见光通道、高分辨率地形及地表反照率等数据,改善地面入射太阳辐射产品质量与空间分辨率,利用辐射计算模型(Hybrid)模型与地面站日照时数、气温等观测资料模拟地面太阳辐射,并利用多重网格变分分析技术实现二者融合;实现东亚多卫星集成降水产品(EMSIP)与4万余自动站观测降水融合,并实时生成格点融合产品,针对陆面模拟分辨率高、数据量大的特点,设计了分块并行与模式并行结合的计算方案,建立了高效的土壤湿度模拟产品业务系统,有效地推动各级气象部门开展相关业务应用工作。展开更多
This study uses data covering 3,914 farm households,collected from Henan province in China,to investigate the links between the price of agricultural mechanization services and farmers'exit from land operation.The...This study uses data covering 3,914 farm households,collected from Henan province in China,to investigate the links between the price of agricultural mechanization services and farmers'exit from land operation.The results indicate that the increasing price of agricultural mechanization services leads tofarmers leaving land operation,especially when the high sunk costs and the long-term breakeven period of self-owned machinery are considered.This effect is intensified by the rapid rural-urban migration in China.Further analysis reveals that the surge in service prices reduced land renting-in and encouraged non-grain production.Our analysis suggests that the agricultural mechanization service market in China tends to work against the survival of smallholder farmers.However,the price of agricultural mechanization services is conducive to eliminating less-productive farmers and cultivating new agricultural operators.展开更多
文摘回顾了中国气象局高分辨率陆面数据同化系统(High Resolution China Meteorological Administration Land Data Assimilation System,HRCLDAS)的研发历程,重点介绍了HRCLDAS研发过程中的重要进展和突破,概要阐述了这些进展对HRCLDAS业务化的贡献。主要包括:引入1 km分辨率地形数据,采用多重网格变分分析技术制作1 km分辨率气象驱动数据;基于FY-2卫星1 km可见光通道、高分辨率地形及地表反照率等数据,改善地面入射太阳辐射产品质量与空间分辨率,利用辐射计算模型(Hybrid)模型与地面站日照时数、气温等观测资料模拟地面太阳辐射,并利用多重网格变分分析技术实现二者融合;实现东亚多卫星集成降水产品(EMSIP)与4万余自动站观测降水融合,并实时生成格点融合产品,针对陆面模拟分辨率高、数据量大的特点,设计了分块并行与模式并行结合的计算方案,建立了高效的土壤湿度模拟产品业务系统,有效地推动各级气象部门开展相关业务应用工作。
基金Key Project of National Social Science Fund of China(No.20FGLA004).
文摘This study uses data covering 3,914 farm households,collected from Henan province in China,to investigate the links between the price of agricultural mechanization services and farmers'exit from land operation.The results indicate that the increasing price of agricultural mechanization services leads tofarmers leaving land operation,especially when the high sunk costs and the long-term breakeven period of self-owned machinery are considered.This effect is intensified by the rapid rural-urban migration in China.Further analysis reveals that the surge in service prices reduced land renting-in and encouraged non-grain production.Our analysis suggests that the agricultural mechanization service market in China tends to work against the survival of smallholder farmers.However,the price of agricultural mechanization services is conducive to eliminating less-productive farmers and cultivating new agricultural operators.
