Abstract Project: AWIPEV_0010

Marion Maturilli (AWI)

Water vapour is a chemically, physically, and radiatively active trace gas, and its distribution in the stratosphere determines significant climatic implications. Besides methane oxidation in the upper stratosphere, the main source of stratospheric H2O is the tropical tropopause region. Yet, the water vapour distribution in the Arctic stratosphere bares evidence for dynamical aspects on different scales, describing the large scale descending motion inside the polar vortex as well as filamentary structures at the vortex edge linked to Rossby wave activity. In the presence of very low temperatures, the sedimentation of polar stratospheric cloud (PSC) ice particles can lead to dehydration. With our high resolution measurements in the Arctic we contribute to the assessment of the water vapour distribution in the stratosphere. The measurements are part of the GRUAN redundant observations for radiosounding, and they contribute to the Network for the Detection of Atmospheric Compositin Changes (NDACC).