Satellite observations of the quasi 5-day wave in noctilucent clouds and mesopause temperatures

Abstract

We report on simultaneous measurements of the westward propagating quasi 5-day wave in the occurrence rate of noctilucent clouds (NLCs) and the temperature field at NLC altitude during the 2005 NLC season in the northern hemisphere. NLCs are detected using SCIAMACHY/Envisat limb scattering measurements, and the temperature profiles are measured with MLS/Aura. Quasi 5-day wave signatures are clearly identified in both physical and wavelet space. We find good general agreement in the quasi 5-day wave activity of NLC occurrence rates and the mesopause temperature field, indicating that planetary wave signatures in the temperature field are the main driver of corresponding signatures in NLCs. Copyright 2007 by the American Geophysical Union.