Impact of meteor showers on mesospheric smoke particles

This proposal covers expenses for data analysis of the 2008 ECOMA rocket campaign, in cooperation with Institute of Atmospheric Physics (IAP) in Kühlungsborn, Germany. In the campaign, we launched three rockets from Andøya into the polar mesosphere, to s tudy properties of mesospheric aerosol particles. The rockets carried instruments to measure the density of charged and neutral aerosol particles, collect samples to be analysed in the laboratory, as well as plasma instruments. In addition, ground-based lidar and microwave instruments were used to measure temperature and humidity. The data analysis will also make use of a numerical model for the interaction between aerosol particles and the ambient electrons and ions. The main purpose of the 2008 camp aign was to measure the density of the very small "smoke" particles, believed to be the condensation nuclei of mesospheric ice particles, when Polar Mesospheric Summer Echoes (PMSE) and Noctilucent Clouds (NLC) are present. Previous measurements indicate that the smoke particle density may be too small to cause PMSE and NLC. Secondly, one launch was carried out when the atmosphere was sufficiently cold for PMSE and NLC to form, yet PMSE and NLC were absent in some of the heights, to determine whether th e absence of ice particles is caused by a lack of available condensation nuclei.