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Dr. Christian Hogrefe

Christian Hogrefe is a Research Physical Scientist in the Emissions and Model Evaluation Branch in the Atmospheric Modeling and Analysis Division. He previously worked as Research Scientist at the New York State Department of Environmental Conservation and as Adjunct Research Associate at the Atmospheric Sciences Research Center, State University of New York. His core expertise is in the application and evaluation of air quality modeling systems and the analysis of atmospheric measurements. Past and present research interests include the evaluation of air quality models to help guide air quality management decisions, the simulation of air quality under present and future regional climate scenarios, the integration of air quality observations and long-term air quality model predictions for potential use in health impact studies, and the use of photochemical models for real-time air quality forecasting.

Christian Hogrefe

Biographical Information

Name: Christian Hogrefe
Title: Research Physical Scientist

Contact Info:

Atmospheric Modeling and Analysis Division
National Exposure Research Laboratory
Environmental Protection Agency
109 TW Alexander Drive
Rsearch Triangle Park, NC 27711

Phone: 919-541-5362
email: hogrefe.christian@epa.gov

Education
B.S. in Physics, University of Regensburg, Germany and University of Heidelberg, Germany, 1993/1994
M.S. in Atmospheric Sciences, State University of New York at Albany, 1996
Ph.D. in Atmospheric Sciences, State University of New York at Albany, 2000

Professional Experience
Research Physical Scientist, Emissions and Model Evaluation Branch, Atmospheric Modeling and Analysis Division, U.S. EPA, Research Triangle Park, NC, 2011- present
Research Scientist 2, Bureau of Air Quality Analysis and Research, New York State Department of Environmental Conservation, Albany, NY, 2008 – 2011
Air Pollution Meteorologist 3, Bureau of Air Quality Analysis and Research, New York State Department of Environmental Conservation, Albany, NY, 2000 – 2008
Adjunct Research Associate, Atmospheric Sciences Research Center, State University of New York at Albany, Albany, NY, 2001 - 2011
Research Scientist, Research Foundation of the State University of New York, Albany, NY, 2002 – 2007
Postdoctoral Research Associate, Research Foundation of the State University of New York, Albany, NY, 2000 - 2001
Research Assistant, Research Foundation of the State University of New York, Albany, NY, 1995 – 2000

Professional Societies and Affiliations
Air and Waste Management Association
American Meteorological Society
American Geophysical Union

Awards and Honors
Oak Ridge Institute for Science and Education (ORISE) research scholarship, 2006 - 2008
Community Modeling and Analysis System (CMAS) Center award "for outstanding achievements in advancing and promoting the ideals of the community model paradigm," 2003
Paul C. Lemon Biennial Doctoral Dissertation Award "for a thesis that is an outstanding contribution to our understanding of the ecological and environmental problems, inter-relationships and challenges in the natural world," 2001
Narayan R. Gokhale Distinguished Research Award "in recognition of an outstanding doctoral dissertation judged by the faculty as representative of the scholarship and creativity exemplified by the later Professor Narayan R. Gokhale," 2001
Student Merit Award, Eastern New York Regional Chapter of the Air & Waste Management Association, 1999
Academic Excellence Fellowship, Evangelisches Studienwerk Villigst, Schwerte (Germany), 1991 - 1996

Publications and Presentations

Other Publications
Hogrefe, C., W. Hao, E. E. Zalewsky, J.-Y. Ku, B. Lynn, C. Rosenzweig, M. G. Schultz, S. Rast, M. J. Newchurch, L. Wang, P. L. Kinney, and G. Sistla, An analysis of long-term regional-scale ozone simulations over the Northeastern United States: variability and trends, Atmos. Chem. Phys., 11, 567-582., 2011

Hogrefe, C., S.S. Isukapalli, X. Tang, P.G. Georgopoulos, S. He, E.E. Zalewsky, W. Hao, J.-Y. Ku, T. Key, and G.Sistla, Impact of Biogenic Emission Uncertainties on the Simulated Response of O3 and PM2.5 to Anthropogenic Emission Reductions, J. Air Waste Manag. Assoc., 61, 92-108., 2011

Pierce, T., C. Hogrefe, S.T. Rao, P. S. Porter, and J.-Y. Ku, Dynamic Evaluation of a Regional Air Quality Model: Assessing the Weekly Cycle in the Observations and Model Outputs, Atmos. Env., 44, 3583-3596, doi:10.1016/j.atmosenv.2010.05.046, 2010

Doraiswamy, P., C. Hogrefe, W. Hao, K. Civerolo, J.-Y. Ku, and G. Sistla, A Retrospective Comparison of Model-Based Forecasted PM2.5 Concentrations with Measurements, J. Air Waste Manag. Assoc., 1293–1308, doi:10.3155/1047-3289.60.11.1293, 2010

Dennis, R., T. Fox, M. Fuentes, A. Gilliland, S. Hanna, C. Hogrefe, J. Irwin, S.T. Rao, R. Scheffe, K. Schere, D. Steyn, A. Venkatram, A framework for evaluating regional-scale numerical photochemical modeling systems, Environmental Fluid Mechanics, doi:10.1007/s10652-009-9163-2., 2010

Weaver, C.P., X.-Z. Liang , P.J. Adams, P. Amar, J. Avise, M. Caughey, J. Chen, R.C. Cohen, E. Cooter, J.P. Dawson, R. Gilliam, A. Gilliland, A.H. Goldstein, A. Grambsch, A. Guenther, R.A. Harley, S. He, B. Hemming, C. Hogrefe, H.-C. Huang, S. Hunt, D. Jacob, P. Kinney, K. Kunkel, J.-F. Lamarque, B. Lamb, N. Larkin, L.R. Leung, K.-J. Liao, J. Lin, B.H. Lynn, K. Manomaiphiboon, C. Mass, D. McKenzie, L. Mickley, S. ONeil , C. Nolte, S.N. Pandis, P.N. Racherla, C. Rosenzweig, A.G. Russell, E. Salathe, A.L. Steiner, E. Tagaris, Z. Tao, C. Wiedinmyer, A. Williams, D. Winner, J.-H. Woo, S. Wu, D.J. Wuebbles, and J. Zhu. A Preliminary Synthesis of Modeled Climate Change Impacts on U.S. Regional Ozone Concentrations, Bull. Amer. Met. Soc., 90, 1843-1863, 2009

Doraiswamy, P., C. Hogrefe, W. Hao, R.F. Henry, K. Civerolo, J.-Y. Ku, G. Sistla, J.J. Schwab, and K.L. Demerjian, A diagnostic comparison of measured and model-predicted speciated VOC concentrations, Atmos. Environ.,43, doi:10.1016/j.atmosenv.2009.07.056., 2009

Hogrefe, C., B. Lynn, R. Goldberg, C. Rosenzweig, E. Zalewsky, W. Hao, P. Doraiswamy, K. Civerolo, J-Y Ku, G. Sistla, and P.L. Kinney, A Combined Model-Observation Approach to Estimate Historic Gridded Fields of PM2.5 Mass and Species Concentrations, Atmos. Environ., doi:10.1016/j.atmosenv.2009.02.031, 2009

Godowitch, J, C. Hogrefe, and S.T. Rao, Diagnostic Analyses of a Regional Air Quality Model: Changes in Modeled Processes Affecting Ozone and Chemical-Transport Indicators from NOx Point Source Emission Reductions, J. Geophys. Res., 113, D19303, doi:10.1029/2007JD009537, 2008

Cai, C., C. Hogrefe, P. Katsafados, G. Kallos, M. Beauharnois, J.J. Schwab, X. Ren, W.H. Brune, X. Zhou, Y. He, and K.L. Demerjian, Performance Evaluation of an Air Quality Forecast Modeling System for a Summer and Winter Season - Photochemical Oxidants and Their Precursors, Atmos. Environ., 42, doi:10.1016/j.atmosenv.2008.08.029, 2008

Hogrefe, C., K.L. Civerolo, W. Hao, J.-Y. Ku, E.E. Zalewsky, and G. Sistla, Rethinking the Assessment of Photochemical Modeling Systems in Air Quality Planning Applications, J. Air Waste Manag. Assoc., 58, 1086-1099, 2008.

Nolte, C., A.B. Gilliland, C. Hogrefe, and L.J. Mickley, Linking global to regional models to assess future climate impacts on surface ozone levels in the United States, J. Geophys. Res., 113, D14307, doi:10.1029/2007JD008497, 2008

Gilliland, A.B., C. Hogrefe, R.W. Pinder, J.L. Godowitch, and S.T. Rao, Dynamic Evaluation of Regional Air Quality Models: Assessing Changes in O3 Stemming from Emissions and Meteorology, Atmos. Environ., 42 (20), 5110-5123, 2008

Hogrefe, C. W. Hao, K.  Civerolo, J.-Y. Ku, R.S. Gaza, L. Sedefian, G. Sistla, K. Schere, A. Gilliland, and R. Mathur, Daily Photochemical Simulations of Ozone and Fine Particulates Over New York State: Findings and Challenges, J. Appl. Meteor., 46, 961–979, 2007

Bell, M.B., R. Goldberg, C. Hogrefe, P.L.Kinney, K. Knowlton, B.H. Lynn, C. Rosenzweig, J. Rosenthal, and J Patz: Potential effect of climate change on ambient ozone concentrations in 50 US cities, Climatic Change, Volume 82, Numbers 1-2, 61-76, 10.1007/s10584-006-9166-7, 2007

Civerolo, K., C. Hogrefe, B. Lynn, J. Rosenthal, J.-Y. Ku, W. Solecki, J. Cox, C. Small, C. Rosenzweig, R. Goldberg, K. Knowlton, P. Kinney, 2006: Estimating the effects of increased urbanization on surface meteorology and ozone concentrations in the New York City metropolitan region, Atmos. Env., 41, 1803-1818, doi:10.1016/j.atmosenv.2006.10.076, 2007

Hogrefe, C., P.S. Porter, E. Gego, A. Gilliland, R. Gilliam, J. Swall, J. Irwin, and S.T. Rao, Temporal Features in Observed and Simulated Meteorology and Air Quality over the Eastern United States, Atmos. Env., 40, 5041 – 5055, 2006

Gego, E., C. Hogrefe, G. Kallos, A. Voudouri, J.S. Irwin, and S.T. Rao, Examination of model predictions at different horizontal grid resolutions, Env. Fluid Mech., 5, 63-85, 10.1007/s10652-005-0486-3, 2005
Hogrefe, C., B. Lynn, K. Civerolo, J.-Y. Ku, J. Rosenthal, C. Rosenzweig, R. Goldberg, and P.L. Kinney, Simulating changes in regional air pollution due to changes in global and regional climate and emissions, J. Geophys. Res.,Vol. 109, No. D22, D22301, 10.1029/2004JD004690., 2004

Knowlton, K., J. Rosenthal, C. Hogrefe, B. Lynn, S. Gaffin, R. Goldberg, C. Rosenzweig, K. Civerolo, J.-Y. Ku, and P.L. Kinney, Assessing ozone-related health impacts under a changing climate, Env. Health Perspec., 112(15), 1557-1563., 2004

Hogrefe, C., J. Biswas, B. Lynn, K. Civerolo, J.-Y. Ku, J. Rosenthal, C. Rosenzweig, R. Goldberg, and P.L. Kinney, Simulating regional-scale ozone climatology over the Eastern United States: Model evaluation results, Atmos. Env., 38, 2627-2638., 2004

Hogrefe, C., G. Sistla, E.E. Zalewsky, W. Hao, and  J-Y Ku, An assessment of the emissions inventory processing systems, EMS-2001 and SMOKE,  in grid-based air quality models, J. Air Waste Manag. Assoc., 53, 1121-1129., 2003

Hogrefe, C. and S. T. Rao, Demonstrating Attainment of the Air Quality Standards: Integration of Observations and Model Predictions into the Probabilistic Framework. J. Air Waste Manag. Assoc., 51, 1060 – 1072, 2001

Hogrefe, C., S. T. Rao, P. Kasibhatla, G. Kallos, C. Tremback, W. Hao, D. Olerud, A. Xiu, J. McHenry, and K. Alapaty, Evaluating the Performance of Regional-Scale Photochemical Modeling Systems: Part I - Meteorological Model Outputs. Atmos. Env., 35, 4159-4174, 2001

Hogrefe, C., S. T. Rao, P. Kasibhatla, W. Hao, G. Sistla, R. Mathur, and J. McHenry, Evaluating the Performance of Regional-Scale Photochemical Modeling Systems: Part II - Ozone predictions.  Atmos. Env., 35, 4175-4188, 2001

Biswas, J., C. Hogrefe, S. T. Rao, W. Hao, and G. Sistla, Evaluating the Performance of Regional-Scale Photochemical Modeling Systems: Part III - Precursor predictions.  Atmos. Env., 35, 6129 – 6149, 2001

Hogrefe, C., S. T. Rao, I. G. Zurbenko, and P. S. Porter, Interpreting Information in Time Series of Ozone Observations and Model Predictions Relevant to Regulatory Policies in the Eastern United States. Bull. Amer. Met. Soc., 81, 2083 – 2106, 2000

Hogrefe, C., S. T. Rao, and I. G. Zurbenko, Detecting Trends and Biases in Time Series of Ozonesonde Data. Atmos. Env., 32, 2569 – 2586, 1998

Selected Presentations
Hogrefe, C., P. Doraiswamy, B. Colle, K. Demerjian, W. Hao, M. Beauharnois, M. Erickson, M. Souders, and J.-Y. Ku, Effects of Grid Resolution and Perturbations in Meteorology and Emissions on Air Quality Simulations Over the Greater New York City Region, 10th Annual CMAS Conference, October 24-26, 2011, Chapel Hill, NC

Doraiswamy, P., C. Hogrefe, E. Zalewsky, W. Hao, K.L. Demerjian, J.-Y. Ku and G. Sistla, Exploring an Approach to Refine Electric Generating Unit Emissions in Near-Real-time, 10th Annual CMAS Conference, October 24-26, 2011, Chapel Hill, NC

Hogrefe, C., K. Civerolo, W. Hao, E.E. Zalewsky, J.-Y. Ku, P.S. Porter, S.T. Rao, and G. Sistla, Dynamic Evaluation of Long-Term Air Quality Simulations Over the Northeastern United States, 31st NATO ITM on Air Pollution Modeling and Its Application, September 27 – October 1, 2010, Torino, Italy

Hogrefe, C., P. Doraiswamy, B. Colle, K. Demerjian, W. Hao, M. Beauharnois, M. Erickson, M. Souders, J.-Y. Ku, and G. Sistla, Ensemble Air Quality Forecasting: Effects of Perturbations in Meteorology and Emissions, 31st NATO ITM on Air Pollution Modeling and Its Application, September 27 – October 1, 2010, Torino, Italy

Doraiswamy, P., C. Hogrefe, E. Zalewsky, W. Hao, K. Demerjian, J.-Y. Ku and G. Sistla, Impact of temporal fluctuations in power plant emissions on air quality forecasts, 9th Annual CMAS Conference, October 9-11, 2010, Chapel Hill, NC

Doraiswamy, P., C. Hogrefe, W. Hao, K. Civerolo, J. Ku, G. Sistla, and K. Demerjian, Evaluation of Multi-Year Temporal and Spatial Trends in Model- Predicted EC and NO2 Concentrations in Connecticut and Massachusetts, Presented at the 103rd Annual Conference and Exhibition of the Air & Waste Management Association, June 22-25, 2010, Calgary, AB, Canada

Hogrefe, C., W. Hao, E.E. Zalewsky, J.-Y. Ku, B. Lynn, C. Rosenzweig, M. Schultz, S. Rast, M. Newchurch, L. Wang, P.L. Kinney, and G. Sistla, A Comparison of Observed and Simulate Long-Term Ozone Fluctuations and Trends Over the Northeastern United States, 8th Annual CMAS Conference, October 19-21, 2009, Chapel Hill, NC, available online at http://www.cmascenter.org/conference/2009/abstracts/hogrefe_comparison_observed_2009.pdf

Doraiswamy, P., C. Hogrefe, W. Hao, B. Colle, M. Beauharnois, K. Demerjian, J.-Y. Ku and G. Sistla, Preliminary Experiences with the Multi-Model Air Quality Forecasting System for New York State, 8th Annual CMAS Conference, October 19-21, 2009, Chapel Hill, NC, available online at http://www.cmascenter.org/conference/2009/abstracts/doraiswamy_preliminary_experiences_2009.pdf

Ku, J.-Y., C. Hogrefe, W. Hao, and G. Sistla, Assessment of the Impact of the Model Vertical Structure on Air Quality Simulations, poster presented at the 8th Annual CMAS Conference, October 19-21, 2009, Chapel Hill, NC

Hogrefe, C., P. Doraiswamy, B. Colle, M. Erickson, K. Demerjian, W. Hao, M. Beauharnois, J.-Y. Ku, and G.l Sistla, A Multi-Model Air Quality Forecast Guidance System for New York, poster presented at the NYSERDA Envionmental Monitoring, Evaluation, and Protection Conference, October 14-15, 2009, Albany, NY

Porter, P.S., C. Hogrefe, E.Gégo, K. Foley, J.M. Godowitch, and S.T. Rao, Application of Wavelet Filters in an Evaluation of Photochemical Model Perfomance, presented at the 30th NATO/SPS International Technical Meeting on Air Pollution Modeling and its Application, May 18 - 22, 2009, San Francisco.

Hogrefe, C., B. Lynn, C. Rosenzweig, M. Schultz, S. Rast, and P.L. Kinney, Simulating the Impacts of Climate Change and Climate Variability on Air Quality in the Northeastern United States. TF HTAP Workshop on Linkages Between Regional and Global Modeling and Air Quality and Climate Change: Joint Workshop with LRTAP/EMEP TF on Measurements and Modeling, Paris, France 17-19 June 2009

C.G. Nolte, A.B. Gilliland, W. Benjey, D. Loughlin, T. L. Otte, R.W. Pinder, C. Hogrefe, L.J. Mickley, Linking global to regional models to assess future climate impacts on surface ozone levels in the United States. TF HTAP Workshop on Linkages Between Regional and Global Modeling and Air Quality and Climate Change: Joint Workshop with LRTAP/EMEP TF on Measurements and Modeling, Paris, France 17-19 June 2009

P. Doraiswamy, C. Hogrefe, W. Hao, K. Civerolo, J. Ku, G. Sistla, H. Zhang, Comparison of Model Predicted PM2.5 Concentrations With Satellite Based Aerosol Optical Depth Measurements. Presented at the 102nd Annual Conference and Exhibition of the Air & Waste Management Association, June 15-19, 2009, Detroit, MI

C. Hogrefe, Dynamic Model Evaluation. Invited keynote presentation at the Air Quality Model Evaluation International Initiative (AQMEII) workshop in Stresa, Italy, April 27-29, 2009.

C. Hogrefe, P. Doraiswamy, W. Hao, B. Colle, M. Beauharnois, K. Demerjian, J.-Y. Ku, and G. Sistla,  Multi-Model Air Quality Forecasting over New York State for Summer 2008, CMAS Conference, October 6-8, 2008, Chapel Hill, NC., available online http://www.cmascenter.org/conference/2008/abstracts/hogrefe_multi-model_air_cmas08.pdf

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