中国空间科学技术 ›› 2023, Vol. 43 ›› Issue (4): 137-148.doi: 10.16708/j.cnki.1000-758X.2023.0062

• 论文 • 上一篇    

一种基于星载遥感的碳通量直接测量方法

吕蒙,张思勃,王磊,姚伟   

  1. 中国空间技术研究院 钱学森空间技术实验室,北京100094
  • 出版日期:2023-08-25 发布日期:2023-07-18

A direct measurement technique of satellite-based CO2 flux

LYU Meng,ZHANG Sibo,WANG Lei,YAO Wei   

  1. Qian Xuesen Laboratory of Space Technology,China Academy of Space Technology,Beijing 100094,China
  • Published:2023-08-25 Online:2023-07-18

摘要: 目前全球尺度碳通量监测主要通过地基原位CO2通量与浓度测量,结合星载遥感CO2浓度等数据源,经过一系列的同化算法加以实现。考虑到原位测量覆盖范围有限,提出一种基于星载遥感的碳通量直接测量方法。基于湍流一阶闭合理论,采用水平风廓线-CO2浓度廓线双廓线模型,结合莫宁奥布霍夫相似理论实现对CO2通量的直接测量。其中水平风廓线通过双视向激光雷达采用多普勒相干测风反演得到,CO2浓度廓线则基于激光雷达的差分吸收原理进行探测。基于星载激光雷达的双廓线探测方案目前可达1m/s的测风精度和10-6的CO2浓度探测精度。通过廓线模型初步分析发现:在较强碳源(例如近地面CO2浓度差>10-5)的下垫面及中性大气条件下可满足目前科学应用对通量数据的精度需求,即实现25%以内的CO2通量测量的不确定度。该方法总体上可提供大尺度碳通量观测数据,作为地基CO2通量测量的有益补充。

关键词: 碳通量测量, 莫宁-奥布霍夫相似理论, 星载遥感, 湍流闭合理论, 多普勒相干测风

Abstract: At present,the mainstream of global carbon flux monitoring is realized through assimilation algorithms by integrating ground-based greenhouse gas flux network and concentration measurement,satellite-based remote sensing greenhouse gas concentration and other data sources.Considering the limited coverage of in-situ measurement,a direct carbon flux measurement method was proposed.The method was based on the first order closure theory of turbulence,adopted the horizontal wind profile and CO2 concentration profile and combined with Monin-Obukhov similarity theory to directly calculate CO2 flux.The horizontal wind profile was retrieved by the dual looking lidar using the coherent Doppler wind measurement method,and the CO2 concentration profile was detected based on the differential absorption principle of the lidar.The method could achieve the current international wind measurement accuracy of 1m/s and the detection accuracy of 10-6 CO2 concentration based on the satellite platform.Through preliminary analysis of the flux model,it is found that under neutral atmospheric condition with strong carbon sources(such as near ground CO2 concentration difference>10-5),the accuracy of the CO2 flux can meet the requirements of scientific application,that is,the uncertainty of CO2 flux measurement within 25% can be achieved.In general,this method can provide large-scale CO2 flux observation data as a meaningful supplement to the in-situ measurement of ground-based carbon flux.

Key words: carbon flux measurement, Monin-Obukhov similarity theory, satellite-based remote sensing, turbulence closure theory, Doppler coherent wind measurement