6533b7ddfe1ef96bd1273d47
RESEARCH PRODUCT
Persistence of orographic mixed‐phase clouds
Jacob P. FugalJacob P. FugalJohannes BühlZamin A. KanjiJan HennebergerOlga HennebergUlrike Lohmannsubject
010504 meteorology & atmospheric sciencesIce crystalsMeteorologyVapor pressure010502 geochemistry & geophysicsAtmospheric sciences01 natural sciencesGeophysicsGeneral Earth and Planetary SciencesEnvironmental scienceClimate modelMixed phasePersistence (discontinuity)SupercoolingSaturation (chemistry)0105 earth and related environmental sciencesOrographic liftdescription
Mixed-phase clouds (MPCs) consist of ice crystals and supercooled water droplets at temperatures between 0 and approximately −38°C. They are thermodynamically unstable because the saturation vapor pressure over ice is lower than that over supercooled liquid water. Nevertheless, long-lived MPCs are ubiquitous in the Arctic. Here we show that persistent MPCs are also frequently found in orographic terrain, especially in the Swiss Alps, when the updraft velocities are high enough to exceed saturation with respect to liquid water allowing simultaneous growth of supercooled liquid droplets and ice crystals. Their existence is characterized by holographic measurements of cloud particles obtained at the high-altitude research station Jungfraujoch during spring 2012 and winter 2013 and simulations with the regional climate model COSMO (Consortium of Small-Scale Modeling).
year | journal | country | edition | language |
---|---|---|---|---|
2016-10-12 | Geophysical Research Letters |