Propagation of medium scale traveling ionospheric disturbances at different latitudes and solar cycle conditions


Corresponding author: M. Hernández-Pajares, Research Group of Astronomy and Geomatics, Universitat Politècnica de Catalunya, ES-08034 Barcelona, Spain. (


[1] In this work, an extension in latitude range and time span with respect previous studies on Medium Scale Traveling Ionospheric Disturbances (MSTID) propagation, is presented. So far they have been basically studied at mid latitude and for limited periods (less than few years) at solar maximum conditions. This extension has been possible due to the availability of local Global Positioning System (GPS) networks at mid-north hemisphere (California), mid-south hemisphere (New Zealand), high and low latitudes (Alaska and Hawaii), for the last 13, 11, 7 and 4 years respectively. Optimal algorithms specially suitable for mass data processing have been used, such as the Single Receiver Medium Scale Traveling Ionospheric activity index (SRMTID) and the phase difference method for MSTID propagation estimation. The results reveal that several of the main MSTID climatological trends at mid latitude are also shared at low and high latitude, also modulated in intensity also by the Solar Cycle. This is the case for local fall/winter day-time equatorward propagated MSTIDs with typical velocities and wavelengths of 150–250 m/s and 100–300 km respectively. Moreover the comparison of MSTID propagation estimation using different techniques, and their implications in terms of potential origins of MSTIDs, are also discussed.