Implementation and evaluation of aerosol and cloud microphysics in a regional climate model

[1] A new aerosol modeling framework is presented within the regional climate model COSMO-CLM. The model accounts for the microphysical interactions of internally and externally mixed aerosol particles. Sulfate, black carbon, particulate organic matter, sea salt, and mineral dust are considered. The model is applied over Europe at a horizontal resolution of 50 km. The lateral boundary conditions are given by the ERA-Interim reanalysis for the meteorological fields and by a global ECHAM5-HAM simulation for the aerosols. Present-day AeroCom emissions are used for the evaluation period from 1997 to 2003. The model largely reproduces the annual mean pattern of the aerosol optical depth derived from satellite data over Europe (model and observed domain mean is 0.17, but it is 0.37 with standard model version). The annual cycle is overestimated in COSMO-CLM in some regions due to strong dust transport across the Mediterranean in late spring. Day-to-day variability in aerosol optical depth and the Angstrom exponent is also captured by the model. The corresponding correlations of the daily mean time series between measurements from AERONET stations and the model range from 0.17 to 0.74. In comparison with the standard model version, which does not account for aerosol transport and indirect aerosol effects and uses an outdated aerosol climatology, the mid-European summer cold bias disappears with the new framework. The new framework allows studies of mesoscale interactions between aerosols, clouds, precipitation, and radiation on climatological time scales due to the advanced physical representation of the underlying processes.

[1]  T. Eck,et al.  Variability of Absorption and Optical Properties of Key Aerosol Types Observed in Worldwide Locations , 2002 .

[2]  A. Korolev,et al.  In situ measurements of effective diameter and effective droplet number concentration , 1999 .

[3]  U. Lohmann.  Possible Aerosol Effects on Ice Clouds via Contact Nucleation , 2002 .

[4]  Corinna Hoose,et al.  The global influence of dust mineralogical composition on heterogeneous ice nucleation in mixed-phase clouds , 2008 .

[5]  S. Twomey.  The Influence of Pollution on the Shortwave Albedo of Clouds , 1977 .

[6]  Richard G. Jones,et al.  An inter-comparison of regional climate models for Europe: model performance in present-day climate , 2007 .

[7]  Ulrike Lohmann,et al.  Sensitivity Studies of the Importance of Dust Ice Nuclei for the Indirect Aerosol Effect on Stratiform Mixed-Phase Clouds , 2006 .

[8]  Knut Stamnes,et al.  Radiative Energy Budget in the Cloudy and Hazy Arctic , 1989 .

[9]  P. J. Rasch,et al.  A comparison of scavenging and deposition processes in global models: results from the WCRP Cambridge Workshop of 1995 , 2000 .

[10]  J. Pal,et al.  Mean, interannual variability and trends in a regional climate change experiment over Europe. I. Present-day climate (1961–1990) , 2004 .

[11]  Alexander Smirnov,et al.  Cloud-Screening and Quality Control Algorithms for the AERONET Database , 2000 .

[12]  W. Slinn,et al.  Predictions for particle deposition on natural waters , 1980 .

[13]  H. Köhler.  The nucleus in and the growth of hygroscopic droplets , 1936 .

[14]  U. Lohmann,et al.  A study of internal and external mixing scenarios and its effect on aerosol optical properties and direct radiative forcing , 2002 .

[15]  Kathleen A. Crean,et al.  Regional aerosol retrieval results from MISR , 2002, IEEE Trans. Geosci. Remote. Sens..

[16]  M. Tiedtke.  A Comprehensive Mass Flux Scheme for Cumulus Parameterization in Large-Scale Models , 1989 .

[17]  Stephan Havemann,et al.  A new parametrization for the radiative properties of ice crystals: Comparison with existing schemes and impact in a GCM , 2007 .

[18]  Martin Wild,et al.  Trends in aerosol radiative effects over Europe inferred from observed cloud cover, solar “dimming,” and solar “brightening” , 2007 .

[19]  S. Seneviratne,et al.  Analysis of ERA40-driven CLM simulations for Europe , 2008 .

[20]  Yoram J. Kaufman,et al.  Aerosol distribution in the Northern Hemisphere during ACE‐Asia: Results from global model, satellite observations, and Sun photometer measurements , 2004 .

[21]  K. Diehl,et al.  Heterogeneous Drop Freezing in the Immersion Mode: Model Calculations Considering Soluble and Insoluble Particles in the Drops , 2004 .

[22]  A. Watson,et al.  In situ evaluation of air‐sea gas exchange parameterizations using novel conservative and volatile tracers , 2000 .

[23]  E. Shettle,et al.  A New Background Stratospheric Aerosol Model for Use in Atmospheric Radiation Models , 1988 .

[24]  G. M. Hale,et al.  Optical Constants of Water in the 200-nm to 200-microm Wavelength Region. , 1973, Applied optics.

[25]  F. Giorgi,et al.  PRUDENCE employs new methods to assess European climate change , 2002 .

[26]  O. Boucher,et al.  The aerosol-climate model ECHAM5-HAM , 2004 .

[27]  C. Long,et al.  From Dimming to Brightening: Decadal Changes in Solar Radiation at Earth's Surface , 2005, Science.

[28]  C. Hohenegger,et al.  Sensitivity of the European climate to aerosol forcing as simulated with a regional climate model , 2005 .

[29]  Martin Wild,et al.  Impact of global dimming and brightening on global warming , 2007 .

[30]  Martin Wild,et al.  Global dimming and brightening: A review , 2009 .

[31]  V. Ramanathan,et al.  Aerosols, Climate, and the Hydrological Cycle , 2001, Science.

[32]  U. Lohmann,et al.  Cloud microphysics and aerosol indirect effects in the global climate model ECHAM5-HAM , 2007 .

[33]  D. Mitchell,et al.  The relationships among cloud microphysics, chemistry, and precipitation rate in cold mountain clouds , 2000 .

[34]  A. Sterl,et al.  The ERA‐40 re‐analysis , 2005 .

[35]  U. Lohmann,et al.  Sensitivity Studies of Aerosol–Cloud Interactions in Mixed-Phase Orographic Precipitation , 2009 .

[36]  P. Seibert,et al.  A study of an outstanding Saharan dust event at the high-alpine site Jungfraujoch, Switzerland , 1995 .

[37]  P. V. Velthoven,et al.  Observations of aerosols in the free troposphere and marine boundary layer of the subtropical Northeast Atlantic: Discussion of processes determining their size distribution , 1997 .

[38]  M. Petters,et al.  A single parameter representation of hygroscopic growth and cloud condensation nucleus activity , 2006 .

[39]  U. Lohmann,et al.  Water uptake of clay and desert dust aerosol particles at sub- and supersaturated water vapor conditions. , 2009, Physical chemistry chemical physics : PCCP.

[40]  R. Martin,et al.  Aerosol size-dependent below-cloud scavenging by rain and snow in the ECHAM5-HAM , 2009 .

[41]  R. Rotty.  A look at 1983 CO2 emissions from fossil fuels (with preliminary data for 1984) , 1987 .

[42]  H. Hansson,et al.  Hygroscopic growth of aerosol particles in the Po Valley , 1992 .

[43]  B. Ritter,et al.  A comprehensive radiation scheme for numerical weather prediction models with potential applications in climate simulations , 1992 .

[44]  J. Steppeler,et al.  Meso-gamma scale forecasts using the nonhydrostatic model LM , 2003 .

[45]  G. d’Almeida,et al.  A model for Saharan dust transport , 1986 .

[46]  B. Rockel,et al.  The performance of the regional climate model CLM in different climate regions, based on the example of precipitation , 2008 .

[47]  T. Eck,et al.  An emerging ground-based aerosol climatology: Aerosol optical depth from AERONET , 2001 .

[48]  Chris Hewitt,et al.  Ensembles-based predictions of climate changes and their impacts , 2004 .

[49]  B. Barkstrom,et al.  Cloud-Radiative Forcing and Climate: Results from the Earth Radiation Budget Experiment , 1989, Science.

[50]  G. Kallos,et al.  Saharan dust contributions to PM10 and TSP levels in Southern and Eastern Spain , 2001 .

[51]  K. D. Beheng,et al.  A two-moment cloud microphysics parameterization for mixed-phase clouds. Part 1: Model description , 2006 .

[52]  T. D. Mitchell,et al.  An improved method of constructing a database of monthly climate observations and associated high‐resolution grids , 2005 .

[53]  George A. Isaac,et al.  Physical and chemical observations in marine stratus during the 1993 North Atlantic Regional Experiment: Factors controlling cloud droplet number concentrations , 1996 .

[54]  B. Albrecht.  Aerosols, Cloud Microphysics, and Fractional Cloudiness , 1989, Science.

[55]  U. Lohmann,et al.  In situ determination of atmospheric aerosol composition as a function of hygroscopic growth , 2008 .

[56]  U. Lohmann,et al.  Sensitivity Studies of the Role of Aerosols in Warm-Phase Orographic Precipitation in Different Dynamical Flow Regimes , 2008 .

[57]  J. Wilson,et al.  A modeling study of global mixed aerosol fields , 2001 .

[58]  Johann Feichter,et al.  Simulation of the tropospheric sulfur cycle in a global climate model , 1996 .

[59]  Lorraine A. Remer,et al.  Smoke Invigoration Versus Inhibition of Clouds over the Amazon , 2008, Science.

[60]  James A. Weinman,et al.  Radiative Properties of Carbonaceous Aerosols , 1971 .

[61]  J. Hansen,et al.  Light scattering in planetary atmospheres , 1974 .

[62]  Ulrike Lohmann,et al.  Can aerosols spin down the water cycle in a warmer and moister world? , 2004 .

[63]  S. Solomon.  The Physical Science Basis : Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change , 2007 .

[64]  F. Volz,et al.  Infrared absorption by atmospheric aerosol substances , 1972 .

[65]  P. Jones,et al.  A European daily high-resolution gridded data set of surface temperature and precipitation for 1950-2006 , 2008 .

[66]  E. van Meijgaard,et al.  Summertime inter-annual temperature variability in an ensemble of regional model simulations: analysis of the surface energy budget , 2007 .

[67]  D. Tanré,et al.  Remote sensing of aerosol properties over oceans using the MODIS/EOS spectral radiances , 1997 .

[68]  H. Neckel,et al.  Transformation of the absolute solar radiation data into the ‘International Practical Temperature Scale of 1968’ , 1970 .

[69]  Ulrike Lohmann,et al.  Erratum: ``Prediction of the number of cloud droplets in the ECHAM GCM'' , 1999 .

[70]  E. Vermote,et al.  Operational remote sensing of tropospheric aerosol over land from EOS moderate resolution imaging spectroradiometer , 1997 .

[71]  J. Lelieveld,et al.  A dry deposition parameterization for sulfur oxides in a chemistry and general circulation model , 1998 .

[72]  Kenneth C. Young,et al.  A Numerical Simulation of Wintertime, Orographic Precipitation: Part I. Description of Model Microphysics and Numerical Techniques , 1974 .

[73]  Roger Jones,et al.  Regional climate projections , 2007 .

[74]  A. Bott.  A positive definite advection scheme obtained by nonlinear renormalization of the advective fluxes , 1989 .

[75]  U. Lohmann,et al.  Aerosol processing in mixed‐phase clouds in ECHAM5‐HAM: Model description and comparison to observations , 2008 .

[76]  M. Rummukainen,et al.  Evaluating the performance and utility of regional climate models: the PRUDENCE project , 2007 .

[77]  Sundar A. Christopher,et al.  Longwave radiative forcing of Saharan dust aerosols estimated from MODIS, MISR, and CERES observations on Terra , 2003 .

[78]  郑楚光,et al.  Stochastic algorithm and numerical simulation for drop scavenging of aerosols , 2006 .

[79]  Tami C. Bond,et al.  Emissions of primary aerosol and precursor gases in the years 2000 and 1750 prescribed data-sets for AeroCom , 2006 .

[80]  Irina N. Sokolik,et al.  Modeling the radiative characteristics of airborne mineral aerosols at infrared wavelengths , 1998 .

[81]  J. Wilson,et al.  M7: An efficient size‐resolved aerosol microphysics module for large‐scale aerosol transport models , 2004 .

[82]  C. Schär,et al.  Towards climate simulations at cloud-resolving scales , 2008 .

[83]  R. Martin,et al.  Influences of in-cloud aerosol scavenging parameterizations on aerosol concentrations and wet deposition in ECHAM5-HAM , 2009 .

[84]  A. Gaudichet,et al.  Saharan dust deposition over Mont Blanc (French Alps) during the last 30 years , 1991 .

[85]  C. Liousse,et al.  Aerosol modelling for regional climate studies: application to anthropogenic particles and evaluation over a European/African domain , 2006 .

[86]  M. Tranter,et al.  The weathering of aeolian dusts in alpine snows , 1996 .

[87]  R. Hemler,et al.  A study of the impact of the Intertropical Convergence Zone on aerosols during INDOEX , 2002 .

[88]  J. Lamarque,et al.  A global simulation of tropospheric ozone and related tracers: Description and evaluation of MOZART, version 2 , 2001 .

[89]  Andrew J. Heymsfield,et al.  An Improved Approach to Calculating Terminal Velocities of Plate-like Crystals and Graupel , 1987 .

[90]  Martin Wild,et al.  Combined surface solar brightening and increasing greenhouse effect support recent intensification of the global land‐based hydrological cycle , 2008 .

[91]  Jonathan Crosier,et al.  Hygroscopicity of the submicrometer aerosol at the high-alpine site Jungfraujoch, 3580 m a.s.l., Switzerland , 2007 .

[92]  C. Frei,et al.  High Resolution Sensitivity Studies with the Regional Climate Model CCLM in the Alpine Region , 2008 .

[93]  C. Hueglin,et al.  Saharan dust events at the Jungfraujoch: detection by wavelength dependence of the single scattering albedo and first climatology analysis , 2004 .

[94]  Peter V. Hobbs,et al.  Fall speeds and masses of solid precipitation particles , 1974 .

[95]  U. Lohmann,et al.  Global indirect aerosol effects: a review , 2004 .

[96]  A. Clarke,et al.  Atmospheric nuclei and related aerosol fields over the Atlantic: Clean subsiding air and continental pollution during ASTEX , 1997 .

[97]  M. Schulz,et al.  Influence of the source formulation on modeling the atmospheric global distribution of sea salt aerosol , 2001 .

[98]  W. Collins,et al.  An AeroCom Initial Assessment - Optical Properties in Aerosol Component Modules of Global Models , 2005 .

[99]  B. Ahrens,et al.  Precipitation by a regional climate model and bias correction in Europe and South Asia , 2008 .

[100]  François-Marie Bréon,et al.  Global distribution of cloud droplet effective radius from POLDER polarization measurements , 2000 .

[101]  H. Hansson,et al.  Hygroscopic growth of aerosol particles and its influence on nucleation scavenging in cloud: Experimental results from Kleiner Feldberg , 1994 .

[102]  Louis J. Wicker,et al.  Time-Splitting Methods for Elastic Models Using Forward Time Schemes , 2002 .

[103]  David R. Doelling,et al.  Toward Optimal Closure of the Earth's Top-of-Atmosphere Radiation Budget , 2009 .

[104]  C. Timmreck,et al.  An improved parameterization for sulfuric acid-water nucleation rates for tropospheric and stratospheric conditions , 2002 .

[105]  Yongxiang Hu,et al.  An Accurate Parameterization of the Radiative Properties of Water Clouds Suitable for Use in Climate Models , 1993 .

[106]  V. Ramanathan,et al.  Reduction of tropical cloudiness by soot , 2000, Science.

[107]  R. Rauber,et al.  Numerical Simulation of the Effects of Varying Ice Crystal Nucleation Rates and Aggregation Processes on Orographic Snowfall , 1986 .

[108]  D. Lüthi,et al.  Aspects of the diurnal cycle in a regional climate model , 2008 .

[109]  D. Lowenthal,et al.  Mountaintop and radar measurements of anthropogenic aerosol effects on snow growth and snowfall rate , 2003 .