Sensitivity of Radiative Fluxes to Aerosols in the ALADIN-HIRLAM Numerical Weather Prediction System

The direct radiative effect of aerosols is taken into account in many limited-area numerical weather prediction models using wavelength-dependent aerosol optical depths of a range of aerosol species. We studied the impact of aerosol distribution and optical properties on radiative transfer, based on climatological and more realistic near real-time aerosol data. Sensitivity tests were carried out using the single-column version of the ALADIN-HIRLAM numerical weather prediction system, set up to use the HLRADIA simple broadband radiation scheme. The tests were restricted to clear-sky cases to avoid the complication of cloud–radiation–aerosol interactions. The largest differences in radiative fluxes and heating rates were found to be due to different aerosol loads. When the loads are large, the radiative fluxes and heating rates are sensitive to the aerosol inherent optical properties and the vertical distribution of the aerosol species. In such cases, regional weather models should use external real-time aerosol data for radiation parametrizations. Impacts of aerosols on shortwave radiation dominate longwave impacts. Sensitivity experiments indicated the important effects of highly absorbing black carbon aerosols and strongly scattering desert dust.

[1]  M. Christensen,et al.  Weak average liquid-cloud-water response to anthropogenic aerosols , 2019, Nature.

[2]  B. Vogel,et al.  Key Issues for Seamless Integrated Chemistry-Meteorology Modeling. , 2017, Bulletin of the American Meteorological Society.

[3]  Kristian Pagh Nielsen,et al.  Effects of aerosols on clear-sky solar radiation in the ALADIN-HIRLAM NWP system , 2016 .

[4]  J. Joseph,et al.  The delta-Eddington approximation for radiative flux transfer , 1976 .

[5]  Yong Wang,et al.  The ALADIN System and its canonical model configurations AROME CY41T1 and ALARO CY40T1 , 2017 .

[6]  Yang Zhang,et al.  Online coupled regional meteorology chemistry models in Europe: current status and prospects , 2013 .

[7]  U. Lohmann,et al.  Anthropogenic aerosol forcing – insights from multiple estimates from aerosol-climate models with reduced complexity , 2019, Atmospheric Chemistry and Physics.

[8]  Jean-François Geleyn,et al.  Single interval shortwave radiation scheme with parameterized optical saturation and spectral overlaps , 2016 .

[9]  P. Koepke,et al.  Optical Properties of Aerosols and Clouds: The Software Package OPAC , 1998 .

[10]  Bent Hansen Sass,et al.  The HIRLAM fast radiation scheme for mesoscale numerical weather prediction models , 2017 .

[11]  J. Mülmenstädt,et al.  Bounding Global Aerosol Radiative Forcing of Climate Change , 2020, Reviews of geophysics.

[12]  Hannu Savijärvi,et al.  Fast radiation parameterization schemes for mesoscale and short-range forecast models , 1990 .

[13]  Mian Chin,et al.  Contribution of different aerosol species to the global aerosol extinction optical thickness: Estimates from model results , 1997 .

[14]  J. Rinne,et al.  Volcanic Impacts Dominate Bidecadal‐Multidecadal Temperature Variations During the Late Holocene in Northern Fennoscandia , 2019, Journal of Geophysical Research: Atmospheres.

[15]  H. Muskatel,et al.  Radiation Effects of Different Types of Aerosol in Eurasia According to Observations and Model Calculations , 2019, Russian Meteorology and Hydrology.

[16]  T. Stanelle,et al.  The comprehensive model system COSMO-ART – Radiative impact of aerosol on the state of the atmosphere on the regional scale , 2009 .

[17]  O. Boucher,et al.  Description and evaluation of the tropospheric aerosol scheme in the European Centre for Medium-Range Weather Forecasts (ECMWF) Integrated Forecasting System (IFS-AER, cycle 45R1) , 2019, Geoscientific Model Development.

[18]  Lisa Bengtsson,et al.  The HARMONIE-AROME Model Configuration in the ALADIN-HIRLAM NWP System , 2017 .

[19]  Xiaohong Liu,et al.  Aerosol indirect effect on the grid-scale clouds in the two-way coupled WRF–CMAQ: model description, development, evaluation and regional analysis , 2013 .

[20]  V. Masson,et al.  The AROME-France Convective-Scale Operational Model , 2011 .

[21]  D. N. Walters,et al.  Impacts of increasing the aerosol complexity in the Met Office global numerical weather prediction model , 2014 .

[22]  D. Dutta,et al.  Estimation of Aerosol-Corrected Surface Solar Irradiance at Local Incidence Angle over Different Physiographic Subdivisions of India and Adjoining Areas Using MODIS and SRTM Data , 2020 .

[23]  M. Sofiev,et al.  SILAM and MACC reanalysis aerosol data used for simulating the aerosol direct radiative effect with the NWP model HARMONIE for summer 2010 wildfire case in Russia , 2015 .

[24]  A. Benedetti,et al.  An aerosol climatology for global models based on the tropospheric aerosol scheme in the Integrated Forecasting System of ECMWF , 2019, Geoscientific Model Development.

[25]  Jean-François Geleyn,et al.  Single interval longwave radiation scheme based on the net exchanged rate decomposition with bracketing , 2017 .

[26]  J. Masek,et al.  Impacts of the direct radiative effect of aerosols in numerical weather prediction over Europe using the ALADIN-HIRLAM NWP system , 2016 .

[27]  A. Baklanov,et al.  Enviro-HIRLAM online integrated meteorology-chemistry modelling system: strategy, methodology, developments and applications (v7.2) , 2017 .

[28]  Henk Eskes,et al.  The CAMS reanalysis of atmospheric composition , 2018, Atmospheric Chemistry and Physics.

[29]  S. Woodward,et al.  Modeling the atmospheric life cycle and radiative impact of mineral dust in the Hadley Centre climate model , 2001 .

[30]  N. Mahowald,et al.  Improved dust representation in the Community Atmosphere Model , 2012 .

[31]  Tsuyoshi Murata,et al.  {m , 1934, ACML.

[32]  L. Rontu,et al.  Renewal of aerosol data for ALADIN-HIRLAM radiation parametrizations , 2019, Advances in Science and Research.