Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 8 1 2008 10.5194/acpd-8-2849-2008 http://www.atmos-chem-phys-discuss.net/8/2849/2008/ http://www.atmos-chem-phys-discuss.net/8/2849/2008/acpd-8-2849-2008.html http://www.atmos-chem-phys-discuss.net/8/2849/2008/acpd-8-2849-2008.pdf 2849 2862 2008-02-13 Correlation between equatorial Kelvin waves and the occurrence of extremely thin ice clouds at the tropical tropopause F. Immler franz.immler@dwd.de K. Krüger M. Fujiwara G. Verver M. Rex O. Schrems German Meteorological Service, Richard-Aßmann-Observatory, Lindenberg, Germany IFM-GEOMAR, Kiel, Germany Hokkaido University, Faculty of Environmental Earth Science, Japan Royal Netherlands Meteorological Institute (KNMI), De Bilt, The Netherlands Alfred Wegener Institute for Polar and Marine Research, Potsdam, Germany Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany A number of field-campaigns in the tropics have been conducted in the recent years with two different LIDAR systems at Paramaribo in Suriname (5.8° N, 55.2° W). The lidars detect particles in the atmosphere with high vertical and temporal resolution and are capable of detecting extremely thin cloud layers which frequently occur in the tropical tropopause layer (TTL). Radiosonde as well as operational ECMWF analysis show that temperature anomalies caused by equatorial Kelvin waves propagate downward, well below the cold point tropopause (CPT). 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