Irregularity Diagnostics by Digital Ionosondes

电离层探测仪作为标准观测站网络仪器的贡献在高层大气学及其目前对空间气象的关注中已得到广泛承认。现代数字研究电离层探测仪，如动力探测仪，不仅扩大了产品的种类、分辨率和动态范围，而且也减少了噪声。事实上，这种“噪音”是高层大气空间天气本质的证据：它是该地区不规则和动态状态的标志。在这一项目中，一些已经证明在这方面取得了重大成功的理论发展将被推广并应用于dynasonde数字电离层探测仪测量。三项新产品包括：1）量化普遍存在的小尺度电离层不规则性的统计参数，如幂律空间频谱的振幅和指数，通常适用于从大约无线电波长到至少无线电菲涅尔尺度的尺度范围。2）小尺度不规则性的外部尺度，当这种尺度可以与归因于大气重力波的更大的不规则性区分开来时。3）利用电离层探测仪的“全天”视图特性，这些量的局部空间多样性。这可能是非常重要的，特别是在赤道和极光区，在强烈的大规模结构的条件。PI将使用在EISCAT极光位置运行的dynasonde的数据;来自犹他州州立大学运行的中纬度熊湖观测站的另一个数据;以及来自1983年3月赤道活动“Condor项目”的数据进行上述研究。

The contributions of ionosondes as standard observatory network instruments are already widely recognized in aeronomy and its current focus on space weather. Modern digital research ionosondes such as the dynasonde expand the variety, resolution and dynamic range of the products, but also of the noise. This 'noise' is, in fact, evidence of the very essence of space weather in the upper atmosphere: It is a signature of the irregular and dynamic state of the region. In this project, some theoretical developments that have already demonstrated substantial successes of this kind are to be extended and applied to dynasonde digital ionosonde measurements. Three new products include:1) Statistical parameters to quantify the prevailing small-scale ionospheric irregularities, such as the amplitude and the index of a power-law spatial spectrum usually applicable in the range of scales extending from about the radio wavelength to at least the radio Fresnel scale.2) An outer scale of the small-scale irregularities, when this can be distinguished from still larger irregularities attributable to Atmospheric Gravity Waves (AGWs).3) Local spatial diversity of these quantities, using the 'all-sky' view characteristic of ionosondes. This can be very important especially in equatorial and auroral regions, during conditions of intense large-scale structuring. The PIs will use data from a dynasonde operating at EISCAT's auroral location; from another at the mid-latitude Bear Lake Observatory operated by Utah State University; and from an equatorial campaign, 'Project CONDOR' of March 1983 for the above studies.