First artificially induced modulation of PMSE using the EISCAT heating facility

A coordinated experiment involving ionospheric heating and VHF observations of polar mesosphere summer echoes (PMSE) has recently been conducted at th e EISCAT facility near Tromso, Norway. We have demonstrated for the first t ime that ionospheric heating can influence VHF radar returns associated wit h PMSE. Artificially elevating the electron temperatures within the PMSE la yer has been shown to reduce the echo power. Based on this and other result s from the experiment, it is suggested that the observed reduction in PMSE power is related to an enhancement of the electron diffusivity through the heating.