中纬度电离层吸收的冬夏不对称性及吸收与低层大气耦合的可能性

本文对1982—1983年期间北京地区一种连续扫频法的电离层吸收记录及国内几个其它台站的f_(min)记录进行了分析。观测证据表明,中纬度电离层D区的吸收行为在冬天和夏天表现很不相同,夏季主要受太阳控制,而冬季则在太阳控制的基础上迭加其它控制因素。对低层大气30mb等压面高度随时间变化的分析结果也显示了类似的冬夏不对称性。这似乎表明,冬天电离层D区更容易受来自对流层和低平流层中某些过程的影响。这与对流层中激发的行星尺度波在冬季易于垂直向上传播的理论是定性上一致的。

THE MORPHOLOGICAL DIFFERENCE OF IONOSPHERICABSORPTION IN SUMMER AND WINTER AT MID-LATITUDES AND THE POSSIBLE COUPLING BETWEEN D-REGION AND LOWER ATMOSPHERE

In this paper both fmin and total absorption data by a sweepfreqeuncy method similar to A3 were analysed for the years 1982-1983 of high solar activity at some mid-latitude stations. An observational evidence was presented that the behaviour of the ionospheric D-region absorption in summer is mainly solar-controlled,but in winter there seems to be an additional factor superimposed. The geopotential height of 30 mb also shows different patterns of its day-by-day variations in summer and in winter. This means that in winter the ionospheric D-region is more easily influenced by meteorological processes generated in tro-po-and lower stratosphere. Theory of vertical propagation of planetary stationary waves was used to explain the observations.