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Ernie R. Lewis

Atmospheric Scientist

Ernie Lewis was originally trained as a physicist. Most recently he was the Principal Investigator of MAGIC, the Marine ARM GPCI Investigation of Clouds, which occurred between September, 2012 and October, 2013. MAGIC, whose goal was to measure properties of clouds and precipitation, aerosols, radiation, and meteorological conditions in the Eastern North Pacific, involved deployment of the Second ARM Mobile Facility (AMF2) on the Horizon Lines cargo ship Spirit as it traversed a route between Los Angeles, CA and Honolulu, HI. Lewis is also the chair of ACCESS, the Atmospheric Chemistry Colloquium for Emerging Senior Scientists, which is held in conjunction with the Gordon Research Conference (GRC) in Atmospheric Chemistry every two years. Lewis previous worked at Brookhaven National Laboratory as a chemical oceanographer and participated in ten oceangoing cruises on which he measured properties of the CO2 system in seawater. Together with D. W. R. Wallace he wrote CO2SYS, which has become the standard program in the oceanographic community for intercalculation of oceanic carbon system parameters. After moving to the Environmental & Climate Sciences Department, his scientific work has focused on understanding properties of aerosols, including sources of natural aerosol production, aerosol dynamics, and the optical and thermodynamic properties of aerosol particles and their dependence on relative humidity. Together with Stephen E. Schwartz, he authored the book Sea Salt Aerosol Production: Mechanisms, Methods, Measurements, and Models—A Critical Review, published by the American Geophysical Union in 2004. His research has involved hygroscopic properties of aerosols, the size dependence of deliquescence and efflorescence of nanoparticles, diffusion of nanoparticles, direct aerosol forcing of climate, modeling the importance of different nucleation mechanisms to aerosol concentrations, and the structure of black carbon-containing aerosol particles.  In April, 2016 he gave the 514th Brookhaven Lecture on "What Will Earth Be Like in 50 Years?", which can be found at


  • California Institute of Technology, B. S. (Honors), Physics
  • von Karman Institute for Fluid Dynamics, Brussels, Belgium, Diploma
  • The University of Texas at Austin, A. B. D., Theoretical Physics


  • American Geophysical Union

Areas of Interest

  • Marine measurements of cloud, aerosol, and radiation properties
  • Biomass burning aerosol particles and the time evolution of their hygroscopic and optical properties
  • Effect of particle size on hygroscopic behavior and on deliquescence and efflorescence
  • The effects of relative humidity on aerosol chemical, physical, and optical properties
  • Phase transitions of aerosol particles; deliquescence and efflorescence
  • Light scattering and radiative transport in the atmosphere
  • Air-sea exchange of gases and particles
  • Physical and chemical properties of electrolyte solutions and their parameterization
  • Sea salt and sea spray aerosols and their properties, concentrations, and production
  • Sources of natural aerosol production
  • Aerosol dynamics and processes in the atmosphere
  • Cloud formation and cloud droplet activation
  • Climate and climate change, and the effect of aerosols on climate change
  • The carbon dioxide system in the oceans
  • Measurement of chemical and physical properties of seawater


  • 1998-present: Environmental & Climate Sciences Department, Brookhaven National Laboratory
  • 1993-1998: Department of Oceanography, Brookhaven National Laboratory


Lewis, E. R. The dependence of radius on relative humidity and solute mass at high relative humidities up to and including 100%.  J. Geophys. Res. Atmos., online, doi:10.1029/2018JD030008 (2019).

Sedlacek III, A. J., Onasch, T. B., Nichman, L., Lewis, E. R., Davidovits, P., Freedman, A., and Williams, L. Formation of Refractory Black Carbon by SP2-Induced Charring of Organic Aerosol. Aerosol Sci. Technol., online, doi:10.1080/02786826.2018.1531107 (2018).

Painemal, D., Chiu, J. Y. C., Minnis, P., Yost, C., Zhou, X., Cadeddu, M., Eloranta, E., Lewis, E. R., Ferrare, R., and Kollias, P. Aerosol and cloud microphysics co-variability in the northeast Pacific boundary layer estimated with ship-based and satellite remote sensing observations. J. Geophys. Res. Atmos. 122, 2403-2418, doi:10.1002/ 2016JD025771 (2017).

DeMott, P. J., T. C. J. Hill, C. S. McCluskey, K. A. Prather, D. B. Collins, R. C. Sullivan, M. J. Ruppel, R. H. Mason, V. Irish, T. Lee, C. Y. Hwang, T. S. Rhee, J. R. Snider, G. R. McMeeking, S. Dhaniyala, E. R. Lewis, J. Wentzell, J. P. D. Abbatt, C. Lee, C. M. Sultana, A. P. Ault, J. I. Axson, M. D. Martinez, I. Venero, G. S. Figueroa, M. D. Stokes, G. B. Deane, O. L. Mayol-Bracero, V. H. Grassian, T. H. Bertram, A. K. Bertram, B. Moffett, & G. D. Franc.  Sea spray aerosol as a unique source of ice nucleating particles.  Proc. Natl. Acad. Sci. 113, 5797-5803, doi:10.1073/pnas.1514034112 (2016).

Yang, W., Marshak, A., McBride, P. J., Chiu, J. C., Knyazikhin, Y., Schmidt, K. S., Flynn, C., Lewis, E. R., and Eloranta, E. W. Observation of the spectrally invariant properties of clouds in cloudy-to-clear transition zones during the MAGIC field campaign. Atmos. Res. 182, 294-301, doi:10.1016/j.atmosres.2016.08.004 (2016).

Feldberg, S. W. and Lewis, E. R. Concentration and Density Changes at an Electrode Surface and the Principle of Unchanging Total Concentration. J. Electrochemical Soc. 163, H3167-H3172, doi:10.1149/2.0231604jes (2016).

Nasiri, S., Williamson, A., Cappa, C. D., Kotamarthi, R., Sedlacek, A. J., Flynn, C., Lewis, E., McComiskey, A., and Riemer, N. Absorbing Aerosols Workshop, January 20-21, 2016. Prepared for U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research, Germantown, Formal Report, BNL-112462-2016, July 2016.

Lewis, E. R. and Teixeira, J. The MAGIC of Clouds. Eos, Transactions, American Geophysical Union 96, doi:10.1029/2015EO031303 (2015).

Sedlacek III, A. J., Lewis, E. R., Onasch, T. B., Lambe, A. T., and Davidovits, P. Investigation of Refractory Black Carbon-Containing Particle Morphologies using the Single-Particle Soot Photometer (SP2). Aerosol Sci. Technol. 49, 872-885, doi:10.1080/02786826.2015.1074978 (2015).

Zhou, X., Kollias, P., and Lewis, E. R.  Clouds, Precipitation and Marine Boundary Layer Structure during the MAGIC Field Campaign. J. Clim. 28, 2420-2442, doi:10.1175/JCLI-D-14-00320.1 (2015).

Lewis, E.  MAGIC studies clouds, aerosols, radiation, and fluxes in the Eastern North Pacific.   SOLAS Newsletter, Issue 16, Summer, 2014, pp. 24-25.

Lewis, E. R. and D. Wallace.  Interactive comment on ‘Comparison of seven packages that compute ocean carbonate chemistry’ by J. C. Orr et al.: Notes on the origin of CO2SYS.   Biogeosciences Discuss. 11, C02014-C02019 (2014).

Meskhidze, N., M. D. Petters, K. Tsigaridis, T. Bates, C. O’Dowd, J. Reid, E. R. Lewis, B. Gantt, M. D. Anguelova, P. V. Bhave, J. Bird, A. H. Callaghan, D. Ceburnis, R. Chang, A. Clarke, G. de Leeuw, G. Deane, P. J. DeMott, S. Elliot, M. C. Facchini, C. W. Fairall, L. Hawkins, Y. Hu, J. G. Hudson, M. S. Johnson, K. C. Kaku, W. C. Keene, D. J. Kieber, M. S. Long, M. Mårtensson, R. L. Modini, C. L. Osburn, K. A. Prather, A. Pszenny, M. Rinaldi, L. M. Russell, M. Salter, A. M. Sayer, A. Smirnov, S. R. Suda, T. D. Toth, D. R. Worsnop, A. Wozniak, and S. R. Zorn.  Production mechanisms, number concentration, size distribution, chemical composition, and optical properties of sea spray aerosol.  Atmos. Sci. Let. 14, doi:10.1002/asl2.441 (2013).

Schwartz, S. E. and E. R. Lewis.  Interactive comment on ‘Are black carbon and soot the same?’ by P. R. Buseck et al.: Disagreement on proposed nomenclature.  Atmos. Chem. Phys. Discuss. 12, C9099-C9109 (2012).

Sedlacek, A. J., III, E. R. Lewis, L. Kleinman, J. Xu, and Q. Zhang.  Determination of and evidence for non-core-shell structure of particles containing black carbon using the single particle soot photometer (SP2).  Geophys. Res. Lett. 39, L06802, doi:10.1029/2012GL050905 (2012).

Kleinman, L. I., P. H. Daum, Y.-N. Lee, E. R. Lewis, A. J. Sedlacek III, G. I. Senum, S. R. Springston, J. Wang, J. Hubbe, J. Jayne, Q. Min, S. S. Yum, and G. Allen.  Aerosol concentration and size distribution measured below, in, and above cloud from the DOE G-1 during VOCALS-Rex.  Atmos. Chem. Phys. 12, 207-223, doi:10.5194/acp-12-207-2012 (2012).

E. R. Lewis and A. J. Sedlacek III.  Interactive comment on ‘Effective density of Aquadag and fullerene soot black carbon reference materials used for SP2 calibration’ by M. Gysel et al.   Atmos. Meas. Tech. Discuss. 4, C1523-C1526, 2011.

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

Bruzewicz, D. A., A. Checco, B. M. Ocko, E. R. Lewis, R. McGraw, and S. E. Schwartz.  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).

Wang, Z., S. M. King, E. Freney, T. Rosenoern, M. Smith, Q. Chen, M. Kuwata, E. R. Lewis, U. Pöschl, W. Wang, P. R. Buseck, and S. T. Martin, The dynamic shape factor of sodium chloride nanoparticles as regulated by drying rate.  Aerosol Sci. Technol. 44, 939-953, doi:10.1080/02786826.2010.503204 (2010).

Lewis, E. R. Comment on “Measurements of the temperature dependent diffusion coefficient of nanoparticles in the range of 295-600 K at atmospheric pressure” by V. Y. Rudyak, S. N. Dubtsov, and A. M. Baklanov.  J. Aerosol Sci. 41, 418-425 (2010).

McGraw, R. and Lewis, E. R. Deliquescence and efflorescence of small particles. J. Chem. Phys. 131, 194705, doi:10.1063/1.3251056 (2009).

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).

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

Lewis, E. R. An examination of Köhler theory resulting in an accurate expression for the equilibrium radius ratio of a hygroscopic aerosol particle valid up to and including relative humidity 100%. J. Geophys. Res. 113, D03205, doi:10.1029/2007JD008590 (2008).

Lewis, E. R. The effect of surface tension (Kelvin effect) on the equilibrium radius of a hygroscopic aqueous aerosol particle. J. Aerosol Sci. 37, 1605-1617, doi:10.1016/jaerosci.2006.04.001 (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).

Lewis, E. R. and Schwartz, S. E. Sea Salt Aerosol Production: Mechanisms, Methods, Measurements and Models. Geophysical Monograph Series Vol. 152, American Geophysical Union, Washington, DC, 2004. 413 pp.  Available for purchase at

Johnson, K. M., A. G. Dickson, G. Eischeid, C. Goyet, P. R. Guenther, R. M. Key, K. Lee, E. R. Lewis, F. J. Millero, D. Purkerson, C. L. Sabine, R. G. Schottle, D. W. R. Wallace, & R. J. Wilke, and C. D. Winn, Carbon dioxide, hydrographic, and chemical data obtained during the Nine RV Knorr cruises comprising the Indian Ocean CO2 Survey (WOCE Sections I8SI9S, I9N I8NI5E, I3, I5WI4, I7N, I1, I10 and I2 (December 1, 1994-January 15, 1996), Carbon Dioxide Information and Analysis Center Numeric Data Package (NDP-080), Oak Ridge National Laboratory, U. S. Department of Energy, Oak Ridge, Tennessee, 2002. Available at

Wanninkhof, R., E. Lewis, R. A. Feely, and F. J. Millero,  The optimal carbonate dissociation constants for determining surface water pCO2 from alkalinity and total inorganic carbon.  Mar. Chem., 65, 291-301 (1999).

Millero, F. J., A. G. Dickson, G. Eischeid, C. Goyet, P. R. Guenther, K. M. Johnson, K. Lee, E. Lewis, D. Purkerson, C. L. Sabine, R. Key, R. G. Schottle, D. R. W. Wallace, and C. D. Winn, Assessment of the quality of the shipboard measurements of total alkalinity on the WOCE Hydrographic Program Indian Ocean CO2 survey cruises 1994-1996.  Mar. Chem. 63, 9-20 (1998).

Lewis, E. and D. W. R. Wallace, Program developed for CO2 system calculations, ORNL/CDIAC-105, Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U. S. Department of Energy, Oak Ridge, Tennessee, 1998. Available at as a QBasic, Excel, or MATLAB program, or a program that can be run on Windows, Mac OS X, or iOS (i.e., as an app).

Neill, C, K. M. Johnson, E. Lewis, and D. W. R. Wallace, Accurate headspace analysis of fCO2 in discrete water samples using batch equilibration.  Limn. Oceanog. 42(8), 1774-1783 (1997).

Lewis, E. R. and E. L. Koschmieder, Convection in a rotating, laterally heated annulus. Transition to lower symmetry.  Geophys. Astrophys. Fluid Dyn. 42(1-2), 37-47 (1988).

Wilson, S. and E. Lewis, The SSCene Creed.  Phys. Today 40(3), 13 (1987).

Koschmieder, E. L. and E. R. Lewis, Hadley circulations on a nonuniformly heated rotating plate.  J. Atmos. Sci. 43(21), 2514-2526 (1986).