%0 Conference Paper
%A Petzold, Andreas
%A Rohs, Susanne
%A Rütimann, Mihal
%A Neis, Patrick
%A Florian, Berkes
%A Herman, Smit
%A Martina, Krämer
%A Nicole, Spelten
%A Peter, Spichtinger
%A Philippe, Nedelec
%A Andreas, Wahner
%T Vertical distribution, seasonality and troposphericity of icesupersaturated air masses in the northern mid-latitudes from regular in-situ observations by passenger aircraft
%M FZJ-2021-00856
%D 2020
%X <p>The vertical distribution and seasonal variation of water vapour volume mixing ratio (H<sub>2</sub>O VMR), relative humidity with respect to ice (RH<sub>ice</sub>) and particularly of regions with ice-supersaturated air masses (ISSR) in the extratropical upper troposphere and lowermost stratosphere are investigated at northern mid-latitudes over the regions Eastern North America, the North Atlantic and Europe for the period 1995 to 2010.</p><p>Observation data originate from regular and continuous long-term measurements of H<sub>2</sub>O VMR, temperature and RH<sub>ice</sub> by instrumented passenger aircraft in the framework of the European research program MOZAIC which is continued as European research infrastructure IAGOS (from 2011; see www.iagos.org). The observation data are analysed with respect to the thermal and dynamical tropopauses, as provided by ERA-Interim. Additionally, collocated O<sub>3</sub> observations from MOZAIC are used as tracer for stratospheric air masses.</p><p>Our key results provide in-depth insight into seasonal and regional variability and tropospheric nature of ice-supersaturated air masses at various distances from the tropopause layer. For the vertical distribution and seasonal variation of ISSR occurrence we show a comparison of our results to radio soundings and to satellite observations of cirrus cloud occurrence from AIRS and TOVs Path B instruments. Finally, for all three regions, we investigate the trends and the dependencies of ISSR occurrence on the North Atlantic Oscillation (NAO) index.</p>
%B EGU 2020
%C 4 May 2020 - 8 May 2020, Online (online)
Y2 4 May 2020 - 8 May 2020
M2 Online, online
%F PUB:(DE-HGF)6
%9 Conference Presentation
%R 10.5194/egusphere-egu2020-8992
%U https://juser.fz-juelich.de/record/890275