Study On The Characteristics Of Atmospheric Background Radiation In Near Space

The characteristics of atmospheric background radiation are of great significance to the application of advanced photoelectric engineering and the research of earth and space science.The near space atmosphere is not only affected by the tropospheric activity,but also by the external environment such as solar radiation and cosmic rays.In this paper,the ground-based observation of atmospheric radiation characteristics in special weather is carried out,and the basic change characteristics of atmospheric background radiation and the spatial-temporal distribution state under the upper atmosphere disturbance are analyzed by using the satellite remote sensing data,which provides an important scientific basis for the in-depth study of the formation mechanism and change characteristics of the near space environmental radiation.The main research work and innovative achievements are as follows:The ground-based measurement of the sky background radiation of 0.4-1.1?m was carried out by using the optical fiber spectrometer under the snowstorm in 2018,the basic variation characteristics of the sky background spectral radiation in the whole snowfall process are obtained.At dusk in clear weather after snow,it is observed that the short wave sky background radiation in visible spectrum is lower than the long wave background radiation,while the short wave sky background radiation in other time is higher than the long wave.Based on the infrared radiation data from SABER,the atmospheric disturbance in 2012/2013 was analyzed by perturbation method.It is found that compared with the atmospheric temperature data,the limb long wave infrared radiation data can reveal the atmospheric disturbance more precisely.From January to March 2013,the maximum amplitude of atmospheric temperature disturbance at 40km was 21%,while the maximum amplitude of atmospheric radiation disturbance reached 160%.In 2012,when the effect of stratospheric warming occurred,the maximum value of temperature disturbance was 16.4%,while the maximum value of radiation disturbance was 91%.Based on the statistical analysis of stratospheric sudden warming events in 2013,the temporal and spatial distribution characteristics of atmospheric background radiation are obtained.From the latitude distribution of atmospheric long wave infrared background radiation,it is found that this event occurred in the high latitude area;in the altitude range of 20km-50km,the atmospheric background radiation presents a "w" shape distribution along the longitude direction;there are extreme values near 50km and 80km in the limb atmospheric long wave infrared radiation,and with the occurrence of the event,the above extreme height area presents a trend of first expanding and then shrinking in the high latitude area.Using SABER data,the variation of ozone concentration in the stratospheric sudden warming event in 2013 was studied.In the middle period of stratospheric top uplift,the concentration of ozone increases at 40 km in the high latitude area;in the process of stratospheric sudden warming,the maximum ozone mixing ratio presents the characteristics of mid-high-mid latitude distribution,similar to the blocking high pressure ? type.The correlation about the atmospheric background radiation of 9.6?m channel with ozone concentration,temperature and solar radiation flux is studied in detail.It is found that the radiation value of ozone channel is mainly affected by solar activity,and the ozone concentration is mainly related to temperature in a short time.By using SHARC software,the temporal and spatial variation of atmospheric background radiation in a specific band is simulated,and the diurnal variation of atmospheric background radiation and its variation characteristics with seasons and latitudes are obtained.It is found that the difference between the four seasons of high latitude radiation value is significantly greater than that of low and middle latitude radiation value.According to the radiation generation mechanism,it may be due to the change of atmospheric circulation structure and seasonal transport in high latitude area is stronger than that in the middle and low latitudes.