Research: Forschungszentrum Jülich, IEK-8Forschungszentrum Jülich · Institut für Energie- und Klimaforschung IEK-8: Troposphäre · Global ObservationGermany · Jülich
Research: German Aerospace Center (DLR)German Aerospace Center (DLR) · Institute of Atmospheric Physics · Atmospheric Trace Species - AerosolsGermany · Oberpfaffenhofen
Research: Technische Universität MünchenTechnische Universität München · Institute of Hydrochemistry · Chair for Analytical ChemistryGermany · München
American Association for Aerosol Research AAAR
Dataset: Mueller al JGR 2010aDetlef Müller, Bernadett Weinzierl, Andreas Petzold, Konrad Kandler, Albert Ansmann, T. Müller, Matthias Tesche, Volker Freudenthaler, Michael Esselborn, Birgit Heese, Dietrich Althausen, A. Schladitz, S. Otto, P. Knippertz
Article: MADE-in: a new aerosol microphysics submodel for global simulation of insoluble particles and their mixing stateV. Aquila, J. Hendricks, A. Lauer, N. Riemer, H. Vogel, D. Baumgardner, A. Minikin, Andreas Petzold, J.P. Schwarz, J.R. Spackman, Bernadett Weinzierl, M. Righi, M. Dall'Amico[show abstract] [hide abstract]
ABSTRACT: Black carbon (BC) and mineral dust are among the most abundant insoluble aerosol components in the atmosphere. When released, most BC and dust particles are externally mixed with other aerosol species. Through coagulation with particles containing soluble material and condensation of gases, the externally mixed particles may obtain a liquid coating and be transferred into an internal mixture. The mixing state of BC and dust aerosol particles influences their radiative and hygroscopic properties, as well as their ability of forming ice crystals. We introduce the new aerosol microphysics submodel MADE-in, implemented within the ECHAM/MESSy Atmospheric Chemistry global model (EMAC). MADE-in is able to track mass and number concentrations of BC and dust particles in their different mixing states, as well as particles free of BC and dust. MADE-in describes these three classes of particles through a superposition of seven log-normally distributed modes, and predicts the evolution of their size distribution and chemical composition. Six out of the seven modes are mutually interacting, allowing for the transfer of mass and number among them. Separate modes for the different mixing states of BC and dust particles in EMAC/MADE-in allow for explicit simulations of the relevant aging processes, i.e. condensation, coagulation and cloud processing. EMAC/MADE-in has been evaluated with surface and airborne measurements and mostly performs well both in the planetary boundary layer and in the upper troposphere and lowermost stratosphere.Geoscientific Model Development. 04/2011; 4(2011):325-355.
Andreas Petzold, Richard Marsh, Mark Johnson, Michael Miller, Yura Sevcenco, David Delhaye, Amir Ibrahim, Paul Williams, Heidi Bauer, Andrew Crayford, William D Bachalo, David Raper[show abstract] [hide abstract]
ABSTRACT: The project SAMPLE evaluated methods for measuring particle properties in the exhaust of aircraft engines with respect to the development of standardized operation procedures for particulate matter measurement in aviation industry. Filter-based off-line mass methods included gravimetry and chemical analysis of carbonaceous species by combustion methods. Online mass methods were based on light absorption measurement or used size distribution measurements obtained from an electrical mobility analyzer approach. Number concentrations were determined using different condensation particle counters (CPC). Total mass from filter-based methods balanced gravimetric mass within 8% error. Carbonaceous matter accounted for 70% of gravimetric mass while the remaining 30% were attributed to hydrated sulfate and noncarbonaceous organic matter fractions. Online methods were closely correlated over the entire range of emission levels studied in the tests. Elemental carbon from combustion methods and black carbon from optical methods deviated by maximum 5% with respect to mass for low to medium emission levels, whereas for high emission levels a systematic deviation between online methods and filter based methods was found which is attributed to sampling effects. CPC based instruments proved highly reproducible for number concentration measurements with a maximum interinstrument standard deviation of 7.5%.Environmental Science & Technology 03/2011; 45(8):3562-8. · 4.80 Impact Factor
Article: Climate impact of biofuels in shipping: global model studies of the aerosol indirect effect.[show abstract] [hide abstract]
ABSTRACT: Aerosol emissions from international shipping are recognized to have a large impact on the Earth's radiation budget, directly by scattering and absorbing solar radiation and indirectly by altering cloud properties. New regulations have recently been approved by the International Maritime Organization (IMO) aiming at progressive reductions of the maximum sulfur content allowed in marine fuels from current 4.5% by mass down to 0.5% in 2020, with more restrictive limits already applied in some coastal regions. In this context, we use a global bottom-up algorithm to calculate geographically resolved emission inventories of gaseous (NO(x), CO, SO(2)) and aerosol (black carbon, organic matter, sulfate) species for different kinds of low-sulfur fuels in shipping. We apply these inventories to study the resulting changes in radiative forcing, attributed to particles from shipping, with the global aerosol-climate model EMAC-MADE. The emission factors for the different fuels are based on measurements at a test bed of a large diesel engine. We consider both fossil fuel (marine gas oil) and biofuels (palm and soy bean oil) as a substitute for heavy fuel oil in the current (2006) fleet and compare their climate impact to that resulting from heavy fuel oil use. Our simulations suggest that ship-induced surface level concentrations of sulfate aerosol are strongly reduced, up to about 40-60% in the high-traffic regions. This clearly has positive consequences for pollution reduction in the vicinity of major harbors. Additionally, such reductions in the aerosol loading lead to a decrease of a factor of 3-4 in the indirect global aerosol effect induced by emissions from international shipping.Environmental Science & Technology 03/2011; 45(8):3519-25. · 4.80 Impact Factor
Article: Desert dust aerosol air mass mapping in the western Sahara, using particle properties derived from space-based multi-angle imagingRalph Kahn, Andreas Petzold, Manfred Wendisch, Eike Bierwirth, Tilman Dinter, Michael Esselborn, Marcus Fiebig, Birgit Heese, Peter Knippertz, Detlef Müller, Alexander Schladitz, Wolfgang von Hoyningen-Huene[show abstract] [hide abstract]
ABSTRACT: Coincident observations made over the Moroccan desert during the Sahara mineral dust experiment (SAMUM) 2006 field campaign are used both to validate aerosol amount and type retrieved from multi-angle imaging spectroradiometer (MISR) observations, and to place the suborbital aerosol measurements into the satellite’s larger regional context. On three moderately dusty days during which coincident observations were made, MISR mid-visible aerosol optical thickness (AOT) agrees with field measurements point-by-point to within 0.05–0.1. This is about as well as can be expected given spatial sampling differences; the space-based observations capture AOT trends and variability over an extended region. The field data also validate MISR’s ability to distinguish and to map aerosol air masses, from the combination of retrieved constraints on particle size, shape and single-scattering albedo. For the three study days, the satellite observations (1) highlight regional gradients in the mix of dust and background spherical particles, (2) identify a dust plume most likely part of a density flow and (3) show an aerosol air mass containing a higher proportion of small, spherical particles than the surroundings, that appears to be aerosol pollution transported from several thousand kilometres away.Tellus B - Chemical and Physical Meteorology. 01/2009; 61B:239-251.