ANGEO Annales Geophysicae ANGEO Ann. Geophys. 1432-0576 Copernicus Publications Göttingen, Germany 10.5194/angeo-24-1245-2006 Polar mesosphere winter echoes during MaCWAVE Kirkwood S. 1 Belova E. 1 Blum U. 2 7 Croskey C. 3 Dalin P. 1 Fricke K.-H. 2 Goldberg R. A. 4 Manninen J. 5 Mitchell J. D. 3 Schmidlin F. 6 Swedish Institute of Space Physics, Box 812, 98128 Kiruna, Sweden Physikalisches Institut der Universität Bonn, 53115 Bonn, Germany EE Dept., Pennsylvania State University, University Park, PA 16802, USA NASA/GSFC, Code 612.3, Greenbelt, MD20771, USA Sodankylä Geophysical Observatory, T¨ahteläntie 62 FIN-99600 Sodankylä, Finland Code 972, NASA/GSFC/Wallops Flight Facility, Wallops Is. VA 23337, USA now at: Forsvarets Forskningsinstitutt, N-2027 Kjeller, Norway 03 07 2006 24 4 1245 1255 Copyright: © 2006 S. Kirkwood et al. 2006 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://angeo.copernicus.org/articles/24/1245/2006/angeo-24-1245-2006.html The full text article is available as a PDF file from https://angeo.copernicus.org/articles/24/1245/2006/angeo-24-1245-2006.pdf

During the MaCWAVE winter campaign in January 2003, layers of enhanced echo power known as PMWE (Polar Mesosphere Winter Echoes) were detected by the ESRAD 52 MHz radar on several occasions. The cause of these echoes is unclear and here we use observations by meteorological and sounding rockets and by lidar to test whether neutral turbulence or aerosol layers might be responsible. PMWE were detected within 30 min of meteorological rocket soundings (falling spheres) on 5 separate days. The observations from the meteorological rockets show that, in most cases, conditions likely to be associated with neutral atmospheric turbulence are not observed at the heights of the PMWE. Observations by instrumented sounding rockets confirm low levels of turbulence and indicate considerable small-scale structure in charge density profiles. Comparison of falling sphere and lidar data, on the other hand, show that any contribution of aerosol scatter to the lidar signal at PMWE heights is less than the detection threshold of about 10%.