地球低纬区边缘大气密度的预测

Prediction of atmospheric density at earth edge in low-latitude regions

基于NRLMSISE-00大气模型讨论日地空间环境对地球低纬度地区边缘大气密度的影响,提出预测地球低纬地区边缘大气日平均密度的简化模型法和经验法。简化模型法利用地磁活动和太阳活动的11年准周期特性,通过预测地磁活动和太阳活动的变化规律以预测地球边缘大气密度。经验法则直接利用第23个太阳活动周期的日平均密度变化曲线经过傅里叶变换处理得到日平均密度变化规律曲线,然后将曲线拟合得到不同高度下的密度昼夜波动规律,再利用预测得到的日平均密度即可计算出具体当地时间对应的密度情况。误差分析说明经验预测法比简化模型法精度更高。两种方法均具有较高的精度并且使用方便,可用于地球边缘大气密度的工程化预测计算。

The influence of the space environment on the atmospheric density at earth edge in low-latitude regions is discussed based on the NRLMSISE-00 model. Two methods are proposed to predict the daily average atmospheric density, the simplified model method and the empirical method. The simplified method predicts the values of Av and F/0.7 for the atmospheric density at earth edge in the low-latitude regions in the 11-year period of geomagnetic activity and solar activity. The empirical method directly predicts the value of the future atmospheric density by using the daily average density in the 23rd solar cycle and by means of the Fourier transformation. The diurnal fluctuations in different altitudes can be derived by using the method of fitting curve. Thus the atmospheric density at a local time can be calculated by using the predicted average density. The error analysis for the two methods shows that the empirical method is more accurate than the simplified method. Both methods have high accuracy and are easy to use as engineering prediction algorithms for the atmospheric density at the edge of the earth.