IDENTIFICATION OF HIGH-LATITUDE ACOUSTIC-GRAVITY WAVE SOURCES USING THE GOOSE BAY HF RADAR

Observations of medium-scale acoustic gravity waves using the Goose Ba y HF radar are presented. Data were examined for the period of Novembe r and December 1991, and days that showed evidence of traveling ionosp heric disturbances (TIDs) were selected for analysis. TIDs were identi fied in the HF radar data by quasi-periodic enhancements of the power in the ground-scattered portion of the radar signal. Various parameter s were determined from the data, including the wave frequency, the wav elength, the propagation direction, and the phase velocity. It was fou nd that multiple wave packets from multiple directions are often prese nt simultaneously. Source times and locations were identified from dat a from 2 days, December 5 and 6, 1991, and these were compared with da ta from the Greenland magnetometer chain. The source times and locatio ns were found to correspond to sudden magnetometer deflections, indica ting the correlation of gravity wave sources with the occurrence of io nospheric electrojet current surges, Finally, the source times and loc ations were examined in local time and magnetic latitude, and it was f ound that the sources were clustered in two locations: near the magnet ospheric cusp; and near 1600 MLT at about 75 degrees magnetic latitude .