Stephen E. Schwartz

Senior Scientist

Stephen Schwartz is a senior scientist at Brookhaven National Laboratory and principal investigator in the Department of Energy Atmospheric System Research Program. His research centers on the influences of energy related emissions on climate, with a focus on the role of atmospheric aerosols.

In his research at Brookhaven National Laboratory, Schwartz developed methods to describe the rate of reactions in clouds that lead to production of acid rain. Schwartz's research exerted a major influence on the drafting of the acid deposition section of the 1990 Clean Air Act Amendments. Subsequently his work focused on atmospheric aerosols, which influence a variety of atmospheric processes, from precipitation to climate change. More recently Schwartz has been examining climate change using whole-Earth energy balance models.

Schwartz is author or coauthor of over 130 papers published in peer-reviewed scientific journals. He was editor of Trace Atmospheric Constituents published by Wiley in 1983 and was co-editor of a three volume series Precipitation Scavenging and Atmosphere-Surface Exchange, published by Taylor & Francis in 1992. He is coauthor of Sea Salt Aerosol Production: Mechanisms, Methods, Measurements, and Models — A Critical Review, published by the American Geophysical Union in 2004.

Schwartz served as chief scientist of the Department of Energy's Atmospheric Science Program from 2004 through 2009. He also served on the management team which developed and led the Department of Energy's Atmospheric Radiation Measurement (ARM) Program, from the inception of that program in 1990 until 1999.

Stephen Schwartz lives with his wife, a retired teacher, in Center Moriches, on the south shore of Long Island, where he enjoys canoeing on the Forge River. They have two grown children. Schwartz drives a hybrid gasoline-electric car.

Experience

• Brookhaven National Laboratory, Associate Scientist, 1975-77.
• Brookhaven National Laboratory, Scientist, 1977-90.
• Brookhaven National Laboratory, Senior Scientist, 1990-present.
• Stony Brook University (State University of New York at Stony Brook), Assistant Professor (Chemistry), 1969-75.
• Stony Brook University (State University of New York at Stony Brook), Adjunct Professor (Institute for Terrestrial and Planetary Atmospheres), 1994-97.
• Energieonderzoek Centrum Nederland (Netherlands Energy Research Foundation, ECN), Visiting Scientist, 1996.

Principal Professional Activities

• Chief Scientist, Atmospheric Science Program (ASP), U. S. Department of Energy, 2004-09.
• Co-editor and co-author of several chapters, Atmospheric Aerosol Properties and Impacts on Climate, Climate Change Science Program (U.S.). Synthesis and Assessment Product 2.3, 2009.
• Contributing Author, "Couplings Between Changes in the Climate System and Biogeochemistry" In: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change.
• Science Board, ARM (Department of Energy Atmospheric Radiation Measurement Program) Climate Research Facility, 2004-2006.
• Scientific Steering Committee, National Aerosol-Climate Interactions Program. (NACIP), 2001.
• Lead Scientist, Tropospheric Aerosol Program (TAP), U. S. Department of Energy, 2000-2004.
• Contributing Author, "Aerosols, their Direct and Indirect Effects" and "Radiative Forcing of Climate Change" in Climate Change 2001 - The Scientific Basis, Intergovernmental Panel on Climate Change.
• Steering Committee, Sixth International Conference on Air-Surface Exchange of Gases and Particles, Edinburgh, UK, 2000.
• Co-Convener, Symposium on Physical and Atmospheric Chemistry in Honor of Harold Johnston, American Chemical Society, Division of Physical Chemistry, San Francisco CA, 2000.
• President, Brookhaven Organization of Scientists, 1997-99.
• American Geophysical Union, Committee on Global Environmental Change, 1994-98, and Climate Change Panel, 1998. This committee and panel drafted the initial (1998) AGU Position Statement on Climate Change and Greenhouse Gases.
• Advisory Board, Tellus B, 1997-2003.
• Spotlight Lecture, Colby College, Waterville, ME, 1996.
• Co-chair, Gordon Research Conference, Atmospheric Chemistry, Newport RI, 1995.
• Invited witness, Aerosols and Climate, Hearing on the Science Concerning Global Climate Change, Committee on Energy and Natural Resources, U. S. Senate, Washington, DC, 1994.
• Steering Committee, ACE-2 (Aerosol Characterization Experiment: Radiative Forcing due to Aerosols over the Polluted North Atlantic Region), 1993-97.
• Panel on Atmospheric Effects of Stratospheric Aircraft, National Research Council, 1993.
• Editorial Advisory Board, International Journal of Chemical Kinetics, 1993-95.
• Invited participant, Mission to Washington--Joint Appeal by Religion and Science for the Environment, U. S. Senate, Washington DC, 1992.
• Contributing Author, 1992 IPCC Supplement, Intergovernmental Panel on Climate Change, 1992.
• International Union of Pure and Applied Chemistry, Commission on Atmospheric Chemistry, Associate Member, 1991-94; Titular Member, 1995-98 ; Interdivisional Committee on Nomenclature and Symbols, International Union of Pure and Applied Chemistry, Titular Member, 1998-.
• Co-chair, Fifth International Conference on Precipitation Scavenging and Atmosphere-Surface Exchange Processes, Richland WA, 1991, and Coordinator (with W. G. N. Slinn) of proceedings, published as Precipitation Scavenging and Atmosphere-Surface Exchange, (Hemisphere, Washington DC, 1992).
• North American Editor/Chemistry and Editorial Advisory Board, Urban Atmosphere, 1991-95.
• Primary Co-author, "Atmospheric Process Research and Development", Report 2 of Acidic Deposition: State of Science and Technology, U. S. National Acid Precipitation Assessment Program, Washington DC, 1991.
• Management Team, Atmospheric Radiation Measurement (ARM) Program, Department of Energy, 1990-99.
• Committee on Atmospheric Chemistry, National Research Council, 1988-91.
• Associate Editor, Journal of Geophysical Research - Atmospheres, 1986-89.
• Committee on Atmospheric Chemistry, American Meteorological Society, 1985- 91.
• Associate Editor, Atmospheric Environment, 1984-95.
• Editor, Trace Atmospheric Constituents, Advances in Environmental Science and Technology, Vol. 12 (John Wiley and Sons, New York, 1983).

Publications (since 2006)

Schwartz, S. E., Charlson, R. J., Kahn, R., and Rodhe, H. Earth's Climate Sensitivity: Apparent Inconsistencies in Recent Assessments. Earth's Future, online, doi:10.1002/2014EF000273 (2014).Bengtsson, L. and Schwartz, S. E. Determination of a lower bound on Earth’s climate sensitivity. Tellus B 65, 21533, doi:10.3402/tellusb.v65i0.21533 (2013).

Schwartz, S. E., Charlson, R. J., Kahn, R. A., Ogren, J. A., and Rodhe, H.  Reply to "Comments on 'Why Hasn't Earth Warmed as Much as Expected?'" J. Climate 25, 2200-2204 (2012).

de Leeuw G., Andreas E. L, Anguelova M.D., Fairall C. W., Lewis E. R., O'Dowd C., Schulz M. and Schwartz S. E. Production Flux of Sea-Spray Aerosol. Rev. Geophys 49, RG2001,  doi:10.1029/2010RG000349 (2011).

Schwartz S. E.  Feedback and sensitivity in an electrical circuit: An analog for climate models.  Climatic Change 106, 315-326, doi:10.1007/s10584-010-9903-9 (2011).

Bruzewicz, D. A., Checco A., Ocko B. M., Lewis E. R., McGraw R. and Schwartz S. E.  Reversible uptake of water on NaCl nanoparticles at relative humidity below deliquescence point observed by non-contact environmental AFM. J. Chem. Phys. 134, 044702, doi:10.1063/1.3524195 (2011).

Schwartz S. E., Charlson R. J., Kahn R. A., Ogren, J. A., and Rodhe H.  Why Hasn't Earth Warmed as Much as Expected?  J. Climate 23, 2453-2464, doi:10.1175/2009JCLI3461.1 (2010).

Michalsky J., F. Denn, C. Flynn, G. Hodges, P. Kiedron, A. Koontz, J. Schlemmer, and S. E. Schwartz.  Climatology of aerosol optical depth in North-Central Oklahoma: 1992 - 2008.  J. Geophys. Res. 115, D07203, doi:10.1029/2009JD012197 (2010).

Chang, L.-S., Schwartz, S. E., McGraw, R. and Lewis, E. R.  Sensitivity of aerosol properties to new particle formation mechanism and to primary emissions in a continental scale chemical transport model. J. Geophys. Res. 114, D07203, doi:10.1029/2008JD011019 (2009).

Lohmann, U. and Schwartz, S. E.  Aerosols and Clouds in Chemical Transport Models and Climate Models.  In Clouds in the Perturbed Climate System: Their Relationship to Energy Balance, Atmospheric Dynamics, and Precipitation, Heintzenberg J. and Charlson R. J., Eds. (MIT Press, Cambridge MA, 2009), pp. 531-555. ISBN 978-0-262-01287-4. Ernst Strüngmann Forum.

Quaas J., Bony S., Collins W. D., Donner L., Illingworth A., Jones A., Lohmann U., Satoh M., Schwartz S. E., Tao W.-K., and Wood R.  Current Understanding and Quantification of Clouds in the Changing Climate System and Strategies for Reducing Critical Uncertainties.  In Clouds in the Perturbed Climate System: Their Relationship to Energy Balance, Atmospheric Dynamics, and Precipitation, Heintzenberg J. and Charlson R. J., Eds. (MIT Press, Cambridge MA, 2009), pp. 557-573. ISBN 978-0-262-01287-4. Ernst Strüngmann Forum.

Fast, J.D., Ghan S.J., and Schwartz S.E.  Modeling activities in the Department of Energy's Atmospheric Sciences Program.  Pacific Northwest National Laboratory Report, PNNL-18752, 2009.

Atmospheric Aerosol Properties and Impacts on Climate, Climate Change Science Program (U.S.). Synthesis and Assessment Product 2.3, M. Chin, R. A. Kahn, and S. E. Schwartz, Eds., Washington, DC, 2009.

Kahn, R. A., Yu, H., Schwartz, S. E., Chin, M., Feingold, G., Remer, L. A., Rind, D., Halthore, R., and DeCola, P.  Introduction.  In Atmospheric Aerosol Properties and Impacts on Climate, M. Chin, R. A. Kahn, and S. E. Schwartz, Eds., Chapter 1, Climate Change Science Program (U.S.), Synthesis and Assessment Product 2.3 (pdf), Washington, DC, 2009.

Remote Sensing and In Situ Measurements of Aerosol Properties, Burdens, and Radiative Forcing (pdf). Yu, H., Quinn, P. K., Feingold, G., Remer, L. A., Kahn, R. A., Chin, M., and Schwartz., S. E. In Atmospheric Aerosol Properties and Impacts on Climate, M. Chin, R. A. Kahn, and S. E. Schwartz, Eds., Chapter 2, Climate Change Science Program (U.S.), Synthesis and Assessment Product 2.3, Washington, DC, 2009.

Modeling the Effects of Aerosols on Climate. Rind, D., Chin, M., Feingold, G., Streets, D., Kahn, R. A., Schwartz, S. E., and Yu., H. In Atmospheric Aerosol Properties and Impacts on Climate, M. Chin, R. A. Kahn, and S. E. Schwartz, Eds., Chapter 3, Climate Change Science Program (U.S.), Synthesis and Assessment Product 2.3 (pdf), Washington, DC, 2009.

The Way Forward. Rind, D., Kahn, R. A., Chin, M., Schwartz, S. E., Remer, L. A., Feingold, G., Yu, H., Quinn, P. K., and Halthore, R. In Atmospheric Aerosol Properties and Impacts on Climate, M. Chin, R. A. Kahn, and S. E. Schwartz, Eds., Chapter 4, Climate Change Science Program (U.S.), Synthesis and Assessment Product 2.3, Washington, DC, 2009.

Bauer, S. E., D. Wright, D. Koch, E. R. Lewis, R. McGraw, L.-S. Chang, S. E. Schwartz, and R. Ruedy.  MATRIX (Multiconfiguration Aerosol TRacker of mIXing state): An aerosol microphysical module for global atmospheric models.  Atmos. Chem. Phys. 8, 6003-6035 (2008).

Schwartz, S. E. Uncertainty in climate sensitivity: Causes, consequences, challenges. Energy Environ. Sci. 1, 430-453 (2008).

Schwartz, S. E. Reply to comments by G. Foster et al., R. Knutti et al., and N. Scafetta on "Heat capacity, time constant, and sensitivity of Earth's climate system".  J. Geophys. Res. 113, D15105, doi:10.1029/2008JD009872 (2008).

McComiskey, A., Schwartz, S. E., Schmid, B., Guan, H., Lewis, E. R., Ricchiazzi, P., and Ogren, J. A. Direct aerosol forcing: Calculation from observables and sensitivities to inputs. J. Geophys. Res. 113, D09202, doi:10.1029/2007JD009170 (2008).

Kim, B.-G., Miller, M. A., Schwartz, S. E., Liu, Y., and Min, Q. The role of adiabaticity in the aerosol first indirect effect. J. Geophys. Res. 113, D05210, doi:10.1029/2007JD008961 (2008).

Schwartz S. E.  Heat capacity, time constant, and sensitivity of Earth's climate system.  J. Geophys. Res. 112, D24S05, doi:10.1029/2007JD008746 (2007).

Schwartz, S. E., Charlson, R. J., and Rodhe, H. Quantifying climate change – too rosy a picture. Nature Reports Climate Change 1, 23-24, doi:10.1038/climate.2007.22 (2007).

Ghan, S. J. and Schwartz, S. E. Aerosol properties and processes: A path from field and laboratory measurements to global climate models. Bull. Amer. Meteorol. Soc. 88, 1059-1083, doi:10.1175/BAMS-88-7-1059 (2007).

Wang, J., Daum, P. H., Kleinman, L. I., Lee, Y.-N., Schwartz, S. E., Springston, S. R., Jonsson, H., Covert, D., and Elleman, R. Observation of ambient aerosol particle growth due to in-cloud processes within boundary layers.  J. Geophys. Res. 112, D14207, doi:10.1029/2006JD007989 (2007).

Denman, K.L.; Brasseur, G.; Chidthaisong, A.; Ciais, P.; Cox, P.M.; Dickinson, R.E.; Hauglustaine, D.; Heinze, C.; Holland, E.; Jacob, D.; Lohmann, U.; Ramachandran, S.; Leite daSilva Dias, P.; Wofsy, S.C.; Zhang, X.; Archer, D.; Arora, V.; Austin, J.; Baker, D.; Berry, J.A.; Betts, R.; Bonan, G.; Bousquet, P.; Canadell, J.; Christian, J.; Clark, D.A.; Dameris, M.; Dentener, F.; Easterling, D.; Eyring, V.; Feichter, J.; Friedlingstein, P.; Fung, I.; Fuzzi, S.; Gong, S.; Gruber, N.; Guenther, A.; Gurney, K.; Henderson-Sellers, A.; House, J.; Jones, A.; Jones, C.; Kärcher, B.; Kawamiya, M.; Lassey, K.; Le Quéré, C.; Leck, C.; Lee-Taylor, J.; Malhi, Y.; Masarie, K.; McFiggans, G.; Menon, S.; Miller, J.B.; Peylin, P.; Pitman, A.; Quaas, J.; Raupach, M.; Rayner, P.; Rehder, G.; Riebesell, U.; Rödenbeck, C.; Rotstayn, L.; Roulet, N.; Sabine, C.; Schultz, M.G.; Schulz, M.; Schwartz, S.E.; Steffen, W.; Stevenson, D.; Tian, Y.; Trenberth, K.E.; Van Noije, T.; Wild, O.; Zhang, T.; Zhou, L. Couplings between changes in the climate system and biogeochemistry. In Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Solomon S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor, and H.L. Miller Eds. (Cambridge University Press, Cambridge, UK, 2007) pp. 499-587.

Benkovitz C. M., Schwartz S. E., Jensen M. P. and Miller M. A.  Attribution of Modeled Atmospheric Sulfate and SO2 in the Northern Hemisphere for June-July 1997.  Atmos. Chem. Phys. 6, 4723-4738 (2006).

Yu, S., Eder, B., Dennis, R., Chu, S.-H., and Schwartz, S. E. New unbiased symmetric metrics for the evaluation of air quality models. Atmos. Sci. Lettrs 7, 26-34, doi:10.1002/asl.125 (2006).

Ferrare, R., Feingold, G., Ghan, S., Ogren, J., Schmid, B., Schwartz, S. E. and Sheridan, P. J.  Preface to special section: Atmospheric Radiation Measurement Program May 2003 Intensive Operations Period examining aerosol properties and radiative influences.  Geophys. Res. 111, D05S01, doi:10.1029/2005JD006908 (2006).

Bates, T. S., Anderson, T. L., Baynard, T., Bond, T., Boucher, O., Carmichael, G., Clarke, A., Erlick, C., Guo, H., Horowitz, L., Howell, S., Kulkarni, S., Maring, H., McComiskey, A., Middlebrook, A., Noone, K., O'Dowd, C. D., Ogren, J. A., Penner, J., Quinn, P. K., Ravishankara, A. R., Savoie, D. L., Schwartz, S. E., Shinozuka, Y., Tang, Y., Weber, R. J., and Wu, Y. Aerosol direct radiative effects over the northwest Atlantic, northwest Pacific, and north Indian Oceans: Estimates based on in-situ chemical and optical measurements and chemical transport modeling. Atmos. Chem. Phys. 6, 1657-1732 (2006).

Lewis, E. R. and Schwartz, S. E. Comment on "Size distribution of sea-salt emissions as a function of relative humidity".  Atmos. Environ. 40, 588-590 (2006).