Experimental evidence for dusty plasmas in the polar summer mesosphere using rocket, lidar, and radar measurements
Abstract
The origin of PMSEs (polar mesospheric summer echoes)and their proposed relationship to dust and aerosol particles and to NLCs (noctilucent clouds) are among the most important questions governing the physics of the polar summer mesosphere. Recent studies show increasing evidence for the presence of these particles, and their importance particularly in a charged state. Several recent experimental programs have concentrated on detection of these particles in the MLT (mesosphere and lower thermosphere) region, with an attempt to determine their role in the structure, dynamics and chemistry of the MLT. Here, we concentrate on results of the DROPPS program (Andøya, Norway,1999) and the MaCWAVE program (Andoya, 2002), both of which were designed to study problems relating to this issue. DROPPS involved two rocket sequences in July, 1999. The first launch sequence was nighttime (July 5-6) during the presence of a strong PMSE and a weak NLC. The second sequence (July 13-14) occurred during a bright NLC, but with no PMSE present. MaCWAVE also involved two summertime launch sequences, with emphasis on the influence of gravity waves on the MLT region, but with adequate instrumentation to search for charged dust or aerosols. In this case, launch sequences occurred on the nights of July 1-2, and 4-5, each during the presence of PMSE events. By combining results from the rocket instruments with radar and lidar soundings from ALOMAR Observatory (also at Andøya), it has been possible to analyze each event in sufficient detail to gain an improved understanding of the polar summer MLT and it's response to a dusty plasma environment.
- Publication:
-
35th COSPAR Scientific Assembly
- Pub Date:
- 2004
- Bibcode:
- 2004cosp...35..321G