0000000000310362

AUTHOR

Stephan Fueglistaler

showing 3 related works from this author

Ultrathin Tropical Tropopause Clouds (UTTCs): II. Stabilization mechanisms

2003

Abstract. Mechanisms by which subvisible cirrus clouds (SVCs) might contribute to dehydration close to the tropical tropopause are not well understood. Recently Ultrathin Tropical Tropopause Clouds (UTTCs) with optical depths around 10-4 have been detected in the western Indian ocean. These clouds cover thousands of square kilometers as 200-300 m thick distinct and homogeneous layer just below the tropical tropopause. In their condensed phase UTTCs contain only 1-5% of the total water, and essentially no nitric acid. A new cloud stabilization mechanism is required to explain this small fraction of the condensed water content in the clouds and their small vertical thickness. This work sugges…

[SDU.OCEAN]Sciences of the Universe [physics]/Ocean AtmosphereAtmospheric ScienceSupersaturationWork (thermodynamics)010504 meteorology & atmospheric sciencesChemistry[SDU.OCEAN] Sciences of the Universe [physics]/Ocean AtmosphereEvaporationAtmospheric sciences010502 geochemistry & geophysics01 natural scienceslcsh:QC1-999lcsh:Chemistrylcsh:QD1-999Liquid water content13. Climate actionPhase (matter)Tropical tropopauseddc:550UpwellingCirruslcsh:Physics0105 earth and related environmental sciencesUTTCsultrathin tropical tropospause
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Stratospheric aerosol-Observations, processes, and impact on climate

2016

Interest in stratospheric aerosol and its role in climate have increased over the last decade due to the observed increase in stratospheric aerosol since 2000 and the potential for changes in the sulfur cycle induced by climate change. This review provides an overview about the advances in stratospheric aerosol research since the last comprehensive assessment of stratospheric aerosol was published in 2006. A crucial development since 2006 is the substantial improvement in the agreement between in situ and space-based inferences of stratospheric aerosol properties during volcanically quiescent periods. Furthermore, new measurement systems and techniques, both in situ and space based, have be…

geographygeography.geographical_feature_category010504 meteorology & atmospheric sciencesAir pollutionClimate changeSulfur cyclerespiratory system010502 geochemistry & geophysicsmedicine.disease_causeAtmospheric sciencescomplex mixtures01 natural sciencesAerosolchemistry.chemical_compoundGeophysicschemistryVolcano13. Climate actionAtmospheric chemistryClimatologymedicineEnvironmental scienceClimate model0105 earth and related environmental sciencesCarbonyl sulfideReviews of Geophysics
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Dehydration potential of ultrathin clouds at the tropical tropopause

2003

[1] We report on the first simultaneous in situ and remote measurements of subvisible cirrus in the uppermost tropical troposphere. The observed cirrus, called UTTCs ( ultrathin tropical tropopause clouds), are the geometrically (200-300 m) and optically (t approximate to 10(-4)) thinnest large-scale clouds ever sampled (approximate to10(5) km(2)). UTTCs consist of only a few ice particles per liter with mean radius approximate to5 mum, containing only 1-5 % of the total water. Yet, brief adiabatic cooling events only 1-2 K below mean ambient temperature destabilize UTTCs, leading to large sedimenting particles (r approximate to 25 mm). Due to their extreme altitude above 17 km and low part…

Ice cloudMaterials scienceIce crystalsparticle micro-physicsdehydrationtropical tropopauseRadiusAtmospheric sciencesJTroposphereGeophysicsAltitudeddc:550General Earth and Planetary SciencesCirrussubvisible cirrus cloudsTropopauseStratosphere
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