Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.naic.edu/~astro/talks/abstracts/jhoffner.html Дата изменения: Fri Feb 14 23:25:53 2003 Дата индексирования: Sat Dec 22 10:48:24 2007 Кодировка: Поисковые слова: http astrokuban.info astrokuban

In summer 2001 the mobil potassium lidar of the IAP-KЭhlungsborn was installed near Longyearbyen (78° N) on the north polar island of Spitsbergen which is part of the archipelago Svalbard. At the same place a series of meteorological rockets (`falling spheres', FS) were launched which gave temperatures from the lower thermosphere to the stratosphere. The location of the lidar was chosen to fit inside one of the beams of the Sousy-Radar who is able to observe PMSE about the summer season. The potassium lidar is capable of detecting noctilucent clouds (NLCs) and of measuring temperatures in the lower thermosphere, both under daylight conditions. We give an overview on the NLC measurements (the first at this latitude) and compare the results with temperatures from meteorological rockets and PMSE. The comparison of FS temperatures and NLCs demonstrates that arguments derived from steady-state assumption may not be applicable when relating individual NLC properties to the background thermal field. On the other hand, the mean variation of the NLC and PMSE appearance with height and season is in nice agreement with the climatological variation of the thermal structure in the upper mesosphere. A comparison between NLC and potassium layer show that both do not exist at the same volume. In contrast the PMSE extents well inside to potassium layer and show clear correlations between both .