Ionospheric local model and climatology from long-term databases of multiple incoherent scatter radars

Empirical ionospheric local models have beendeveloped from long-term data sets of seven incoherentscatter radars spanning invariant latitudes from 25 to 75 inAmerican, European and Asian longitudes at Svalbard,Tromsø, Sondrestrom, Millstone Hill, St. Santin, Areciboand Shigaraki. These models, as important complements toglobal models, represent electron density, ion and electrontemperatures, and ion drifts in the E and F regions, giving acomprehensive quantitative description of ionosphericproperties. A case study of annual ionospheric variationsin electron density and ion temperature is presented basedon some of these models. Clear latitudinal, longitudinal, andaltitude dependency of annual and semiannual componentsare found