A new strategy for ionospheric remote sensing using the 130.4/135.6 nm airglow intensity ratios  

作　　者：XiaoHan Yin JianQi Qin Larry J.Paxton 

机构地区：[1]School of Earth and Space Sciences,Peking University,Beijing 100871,China [2]Applied Physics Laboratory,Johns Hopkins University,Laurel,MD 20723,USA

出　　处：《Earth and Planetary Physics》2023年第4期445-459,共15页地球与行星物理（英文版）

基　　金：the National Natural Science Foundation of China through Grant 8206100245;the Chinese Meteorological Administration through Grant FY-APP-ZX-2022.0222.

摘　　要：We demonstrate here that global-scale determination of a key ionospheric parameter,the peak height of the F_(2)region(h_(m)F_(2)),can be obtained by making a simple ratio measurement of the atomic oxygen 130.4 and 135.6 nm emissions in the far-ultraviolet nightglow with a nadir-viewing system such as a pair of photometers suitable for flight on a CubeSat.We further demonstrate that measurements from an altitude that is within the typical range of nighttime h_(m)F_(2)250−450 km can provide the ratios that are needed for retrieval of the h_(m)F_(2).Our study is conducted mostly through numerical simulations by using radiative transfer models of the two emissions coupled with empirical models of the atmosphere and ionosphere.Modeling results show that the relationship between the h_(m)F_(2)and the intensity ratio is sensitive to the altitude from which the emissions are observed,primarily because of the distinctly different degrees of resonant scattering of the two emissions in the atmosphere.A roughly quadratic relationship can be established for observations from an orbit of~400 km,which enables h_(m)F_(2)retrieval.Parametric analysis indicates that the relationship can be affected by the ambient atmospheric conditions through resonant scattering and O2 absorption.For typical nighttime conditions with h_(m)F_(2)250−450 km,retrieval of the h_(m)F_(2)from synthetic observations shows that the typical errors are only a few kilometers(up to~20 km),depending on the accuracy of the ambient conditions predicted by the empirical models.Our findings pave the way for use of the 130.4/135.6 nm intensity ratios for global-scale monitoring of the nighttime ionosphere at mid to low latitudes.

关 键 词：nighttime ionosphere far-ultraviolet remote sensing 130.4/135.6 nm airglow intensity ratio peak height of the F_(2)region(h_(m)F_(2)) TIMED observation 

分 类 号：P352.7[天文地球—空间物理学]