基于风云三号卫星微波资料反演青藏高原土壤湿度及其比较分析

发布时间：2018-05-26 14:22

本文选题：FY-3B + 微波遥感　；参考：《南京信息工程大学》2017年硕士论文

【摘要】：土壤湿度通过改变地表反照率、感热、潜热、调节和控制陆地与底层大气之间的水汽和能量交换,从而对气候和天气过程产生重要影响。本文基于风云三号(FY-3B)卫星微波资料反演了我国青藏高原地区逐目地表土壤湿度。随后将地表参数反演模型(Land Parameter Retrieval Model,LPRM)的土壤湿度数据与 VIC (Variable Infiltration Capacity)水文模型模拟的土.壤湿度数据以及Era-Interim再分析资料进行对比分析;基于那曲地区地表温度站点观测数据对LPRM模型中的地表温度反演模块进行改进,从而提高LPRM模型在青藏高原地区反演的十壤湿度的精度;利用传统统计学方法和TC评估方法对LPRMV06数据在青藏高原地区的十壤湿度数据进行验证分析。得到主要结论如下:(1)就绝对量而言, LPRM反演十壤湿度与那曲地区站点观测数据的偏差较大。ERA-Interim再分析资料与VIC水文模型模型模拟资料的绝对量偏差显著低于LPRM反演土壤湿度。就时间变化而言,LPRM 土壤湿度数据与那曲地区观测数据的相关系数最高,ERA-Interim再分析资料次之,VIC水文模型模拟资料最低。这表明LPRM十壤湿度与观测资料的时间变化最为一致。(2)从时间变化上来看,通过对比暖季期间原始LPRM反演出的十壤湿度数据和改进后的LPRM反演出的土壤湿度数据,结果表明相关系数没有改变,但是绝对量方面得到有效的降低,其中RMSD降低30%, ubRMSD降低10%。(3) LPRMV06土壤湿度数据、ECV 土壤湿度数据和ERA-Interim 土壤湿度数据在三季年际平均分布图中均呈现着青藏高原东南向西北递减的变化特征,而TMI 土壤湿度数据切呈现着自青藏高原东南向西北递减的变化特征。LPRMV06 土壤湿度数据与ECV 土壤湿度数据在青藏高原地区的时间变化一致性最好,与ERA-Interim 土壤湿度数据的时间变化一致性较好,与TMI 土壤湿度数据的时间变化一致性较差;从各个土壤湿度数据的自身空间分布方面而言,四套数据均呈现了东部地区与西部地区的土壤湿度时间变化相反这一特点;从TC比较结果而言,LPRMV06 土壤湿度数据与假设真值的时间变化一致性最好,ECV数据其次,ERA-Interim 土壤湿度数据在青藏高原地区与假设真值的时间变化一致性较差。
[Abstract]:Soil moisture influences the climate and weather process by changing the surface albedo, sensible heat, latent heat, regulating and controlling the water vapor and energy exchange between the land and the lower atmosphere. Based on the FY-3B satellite microwave data of Fengyun No. 3, the surface soil moisture of Qinghai-Xizang Plateau has been retrieved. Then the soil moisture data of Land Parameter Retrieval Model and the soil of VIC variable Infiltration capacity model are simulated. The soil moisture data and Era-Interim reanalysis data are compared and analyzed, and the inversion module of surface temperature in LPRM model is improved based on the ground temperature observation data of Naqu area. In order to improve the accuracy of LPRM model inversion of soil moisture in Qinghai-Tibet Plateau, the traditional statistical method and TC evaluation method are used to verify and analyze the ten soil moisture data from LPRMV06 data in Qinghai-Xizang Plateau. The main conclusions are as follows: (1) in terms of absolute quantity, the deviation between LPRM inversion of soil moisture and the observed data of Naqu station is larger. The absolute deviation of ERA-Interim reanalysis data and VIC hydrological model simulation data is significantly lower than that of LPRM inversion soil moisture. In terms of time variation, the correlation coefficient between soil moisture data of LPRM and observed data in Naqu area is the highest. The simulation data of VIC hydrological model is the lowest, followed by ERA-Interim reanalysis data. This indicates that the temporal variation of LPRM ten soil moisture is the most consistent with that of observed data. (2) from the point of view of time variation, the soil moisture data of the original LPRM reverse performance during warm season and the improved LPRM reverse performance are compared. The results show that the correlation coefficient has not changed, but the absolute quantity has been reduced effectively. Among them, RMSD decreased 30%, ubRMSD decreased 10%) LPRMV06 soil moisture data and ERA-Interim soil moisture data showed the characteristics of decreasing from southeast to northwest of Qinghai-Xizang Plateau in three seasons. However, TMI soil moisture data showed a decreasing trend from southeast to northwest of Qinghai-Xizang Plateau. The temporal variation of LPRMV06 soil moisture data and ECV soil moisture data in Qinghai-Xizang Plateau was the best. The consistency of time variation with ERA-Interim soil moisture data is better than that with TMI soil moisture data. The four sets of data all showed the opposite change of soil moisture time between the eastern region and the western region. From the TC comparison results, the time variation of LPRMV06 soil moisture data and the assumed true value is the best. Secondly, the ERA-Interim soil moisture data in the Qinghai-Xizang Plateau is less consistent with the assumed true value.
【学位授予单位】：南京信息工程大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S152.71

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