以地面稳定目标为参考的网络化定标技术已经成为国际定标领域的研究热点。它利用多次观测的方式减小独立测量不确定性,不仅可极大提升定标校验频次,还可有效提高总体定标精度。基于此,本文利用长时间序列Aqua/MODIS和Landsat8/TIRS热红外数据,对国际卫星对地观测委员会定标与真实性检验组 6个伪不变定标场、敦煌定标场以及格尔木大灶火地区的地表热辐射及大气特性进行了系统性分析,建立了热红外陆表稳定目标甄选标准,即空间亮温标准差低于0.3 K,发射率时间变异系数低于2%,旨在甄选适用于热红外载荷网络化定标的陆表参考目标,以支持热红外载荷在轨辐射定标精度的提升。结果表明：在1 km空间尺度下满足甄选标准的区域分别为：Libya1_1km、Libya4_1km、Algeria3_1km、Algeria5_1km、Mauritania1_1km、Mauritania2_1km、敦煌_1km及格尔木_1km,其中,Libya4_1km面积最大,为75 km 75 km；格尔木_1km面积最小,为3 km 3 km；对于100 m空间尺度,在Libya1_1km、Mauritania1_1km、Mauritania2_1km以及敦煌_1km共甄选出7个满足阈值的区域,最大面积为30 km 30 km,最小面积为5 km 5 km；Libya1_1km、Mauritania1_1km、Mauritania2_1km以及敦煌_1km目标区域的空间均一性受空间尺度影响较小,适用于多种空间分辨率热红外载荷定标与真实性检验。

Networked calibration technology using the Earth surface with suitable characteristics as reference has become a hot topic in the international calibration field. It can reduce the uncertainty of independent measurement by means of multiple observations, so that the calibration frequency and accuracy could be effectively improved. In view of this, long-time series of Aqua / MODIS and Landsat8 / TIRS thermal infrared data are used to systematically analyze the surface thermal radiation and atmospheric characteristics of 8 targets, including six Pseudo Invariant Calibration Sites recommended by the Committee on Earth Observation Satellites (CEOS) WorkingSGroupSonSCalibrationS SValidationS(WGCV), the Dunhuang site and Geermu Dazaohuo area, and meanwhile, a criterion for selecting land surface stable targets are proposed, namely, the spatial standard deviation of brightness temperature should be less than 0.3 K and the emissivity temporal variation coefficient should be less than 2%, so that land surface stable targets suitable for networked calibration of thermal infrared payloads could be selected for improving the in-orbit calibration accuracy of thermal infrared payloads.