典型热层密度模式误差分析

Error Analysis of Typical Atmospheric Density Model

以CHAMP卫星2001年5月15日至2008年12月31日期间2755天的加速度计反演热层大气密度数据为基准,对JB2008和MSISE00两种模式的反演误差进行了统计分析.发现这两种模式整体上均高估了热层大气密度,但JB2008模式的精度优于MSISE00模式.JB2008和MSISE00模式的平均相对误差分别为2.2%和17.6%.对空间环境简要分类,统计各类型事件下热层实测和模式密度的纬度和地方时特性,发现MSISE00模式具有较好的地方时特性,而JB2008模式具有较好的纬度特性.研究结果对掌握目前热层密度模式误差特性及指导模式改进方向具有一定意义.

Based on the density data from May 15, 2001 to Dec. 31, 2008 derived from CHAMP accelerometer, the errors of JB2008 and MSISE00 model are analyzed. The results show that the two models both overestimate the atmospheric density, and the JB2008 model is better than the MSISE00model（the average biases of JB2008 and MSISE00 are 2.2% and 17.6% respectively）. Most relative error of JB2008 mode is from-20% to 20%, the proportion is as high as 89%. However, it is only 58% in the case of MSISE00. The two models have no obvious difference below the height of 450 km, which is consistent with the conclusion of literature. Space environment is classified into four types, and the model characteristics of latitude and local time are analyzed for each kind of space environment.MSISE00 model has better local time characteristics while JB2008 has better latitude characteristics.The results are valuable for mastering the model error characteristics and improving the atmospheric density model.