Seasonal Variation of the propagation parameters of Travelling Ionospheric Disturbances atWallops Island, VA and Tromso, Norway, investigated using Dynasonde measurements.

Catalin Negrea, Institute of Space Sciences, Bucharest, Romania, Nikolay A Zabotin, University of Colorado at Boulder, Department of Electrical, Computer and Energy Engineering, Boulder, CO, United States, Terence W Bullett, Cooperative Institute for Research in Environmental Sciences, Boulder, CO, United States; CIRES - NOAA/NCEI, Boulder, CO, United States and Michael T Rietveld, EISCAT Scientific Association, Ramfjordbotn, Norway