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Impacts of climate change on air pollution levels in the Northern Hemisphere. G. B. Hedegaard 1,2,3 , J. Brandt 1 , J. H. Christensen 1 , L. Frohn 1 , K. M. Hansen 1 , C. Geels 1 , M. Stendel 2 .
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Impacts of climate change on air pollution levels in the Northern Hemisphere G. B. Hedegaard1,2,3, J. Brandt1, J. H. Christensen1, L. Frohn1, K. M. Hansen1, C. Geels1, M. Stendel2. 1: National Environmental Research Institute, Department of atmospheric environment, University of Aarhus, Roskilde, Denmark 2: Danish Meteorological Institute, Copenhagen, Denmark 3: Niels Bohr Institute, Department of Geophysics, University of Copenhagen, Denmark CEEH External Workshop RISØ-DTU, Roskilde, Denmark February 6th – 7th 2008 National Environmental Research Institute, University of Aarhus, Denmark
Background CONSTANT National Environmental Research Institute, University of Aarhus, Denmark
Aim: - To understand and quantify the impacts of a changed climate on air pollution concentrations and depositions in the 21st century. Method: One-way coupling of a climate model to a chemical transport model, constant anthropogenic emissions. National Environmental Research Institute, University of Aarhus, Denmark
Experimental design Climate Model ECHAM4 atmosphere A2 emissions Emission data EMEP-GAIA-EDGAR OPYC3 ocean Sea ice surface/ mixed layer interior 3D advection Chemical Transport Model DEHM 3D dispersion Chemistry Emissions Wet and dry deposition National Environmental Research Institute, University of Aarhus, Denmark
Climate ModelECHAM4-OPYC3 Chemical Transport Model DEHM National Environmental Research Institute, University of Aarhus, Denmark
Emissions in the 4 simulations - Time-sliced experiment in order to save computational time. Simulations 1990s 2090s Variable (MM5 and ECHAM4) Validation Constant 1990 Constant 1990 Future projections National Environmental Research Institute, University of Aarhus, Denmark
Validation • Validation period 1990-1999 • EMEP observations in Europe • Comparison against MM5 simulation with known performance for many chemical species National Environmental Research Institute, University of Aarhus, Denmark
Temperature Annual, averaged temp. 2090s [ºC] Annual, averaged temp. 1990s [ºC] Absolute difference [ºC] Significance National Environmental Research Institute, University of Aarhus, Denmark
Isoprene Annual averaged concentration 1990s [ppbV] Annual averaged concentration 2090s [ppbV] Absolute difference [ppbV] Significance National Environmental Research Institute, University of Aarhus, Denmark
Ozone Annual averaged concentration 1990s [ppbV] Annual averaged concentration 2090s [ppbV] Percentage difference [%] Significance National Environmental Research Institute, University of Aarhus, Denmark
Summary and conclusions • Good performance with respect to mean and seasonal variation • The climate-meteorology can be used as input to the chemical transport model • Temperature increase is the dominating factor • Increase in biogenic VOC emissions (isoprene, ozone precursor) • Ozone and specific humidity increases, enhanced chemical production (more hydroxyl radicals) National Environmental Research Institute, University of Aarhus, Denmark
Current simulations • Improved version of DEHM and ECHAM • A1B scenario • Four decades (1890s, 1990s,2090s and 2190s) National Environmental Research Institute, University of Aarhus, Denmark
Current work and near future • Analysis the data from the four decades (const. emissions) • Simulate the 1990s and 2090s with variable emissions • Sophistication of the natural emitted species in the model (inclusion of particles: Terpenes) • High resolution over Copenhagen + surroundings (1 km x 1 km, street-scale) • Higher regional resolution HIRHAM-DEHM National Environmental Research Institute, University of Aarhus, Denmark
Thank You ! Contacts: Gitte Brandt Hedegaard gbh@dmu.dk www.dmu.dk Reference: Impacts of climate change on air pollution levels with special focus on Europe and the Arctic, G.B. Hedegaard, J. Brandt, J. Christensen, C. Geels, K.M. Hansen and M. Stendel, Atmos. Phys. and Chem. Discuss., 8, 1757-1831, 2008. National Environmental Research Institute, University of Aarhus, Denmark