Sarah J. Doherty

Joint Institute for the Study of the Atmosphere and Ocean
University of Washington
3737 Brooklyn Ave NE
Seattle, WA 98195

Dr. Doherty is a Senior Research Scientist at the Joint Institute for the Study of the Atmosphere and Ocean, a NOAA/University of Washington cooperative institute. She received her PhD in Atmospheric Sciences from the University of Washington in 2001.

Her graduate career followed on six years of work designing and integrating adaptive optics systems (1988-1992) and running experiments for the U.S. Antarctic Program (1992-1994).

Her research to date has primarily focused on measurements of atmospheric aerosol optical properties, with a strong emphasis on instrument development and improvement of measurement techniques. For her PhD she developed the 180degree Backscatter Nephelometer, for which she and colleagues hold a patent.

Following on her Postdoctoral Fellowship, Dr. Doherty became the Executive Officer of the International Global Atmospheric Chemistry (IGAC) project, a position she held for nine years. In this position she helped guide the scientific direction of the organization and was involved in multiple initiatives to synthesize and coordinate multi-national and multi-disciplinary atmospheric chemistry related research.

She left the position at IGAC to return to full-time research at JISAO. Her recent research has focused on a certain type of aerosols, those containing "black carbon" (more commonly known as soot). Climate model studies indicate that black carbon in soot from biomass burning, biofuel burning, transportation and industrial activities warms climate by absorbing sunlight, thereby heating the atmosphere and, when deposited on snow and ice, it can accelerate snow and ice melt. Aerosols containing black carbon also affect clouds, by changing the thermodynamic structure of the atmosphere and by acting as cloud condensation nuclei.

Dr. Doherty and her colleagues in the University of Washington Dept. of Atmospheric Sciences conducted a pan-Arctic campaign to quantify the amount of soot and dust/soil in snow from samples across the Arctic. Model studies indicate that soot in snow is contributing to Arctic warming, and this data set is being used to improve estimates of this warming. She has also collaborated with colleagues in China to made similar measurements across northern China and co-lead an expedition (winters 2013 and 2014) measuring soot in snow in the North American Great Plains region.

More recently her research has shifted back towards the atmosphere: She is a Flight Scientist on the NASA ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) project. ORACLES is using the NASA P3 and ER2 research aircraft to measure smoke from agricultural fires in central Africa. This smoke flows out over the southeast Atlantic ocean. It is known that the smoke affects climate, but the effect is poorly quantified. My making measurements over three years (2016-2018) and working with climate modeling teams to improve simulations of the smoke ORACLES should improve our understanding of how this smoke is affecting regional and global climate.

Dr. Doherty has a particular interest in translating focused research into assessments that address overarching scientific questions of relevance to society. She is second Coordinating Lead Author on a multi-national 2013 paper, “Bounding the role of black carbon in climate: A scientific assessment”. She is one of the Lead Authors on the 2017 "National Climate Assessment Volume I: Climate Science Special Report", and she is currently Assessment Coordinator for the next Scientific Assessment of Ozone Depletion.

Education

01/99-03/01 UNIVERISTY OF WASHINGTON Seattle, WA
Degree: PhD, Atmospheric Science Disseration: "An empirical study of the lidar ratio and its variability, with implications for determining climate forcing by satellite-borne lidar"
Instrument design, development, lab calibration, field deployment and data analysis

05/95-12/97 UNIVERISTY OF WASHINGTON Seattle, WA
Degree: MS, Atmospheric Science Disseration: "The snow surface of the Antarctic ice sheet as a calibration target for visible and UV channels on satellites"

09/84-06/88 COLBY COLLEGE Waterville, ME
Degree: BA, Physics

Work Experience

08/07-present JOINT INSTITUTE FOR THE STUDY OF THE ATMOSPHERE AND OCEAN (JISAO) Seattle, WA
Sr. Research Scientist. Primarily studying black carbon-containing aerosols and their impact on climate.

03/03-02/12 NOAA Pacific Marine Environmental Lab (NOAA-PMEL) Seattle, WA
Executive Officer, International Global Atmospheric Chemsitry Project (IGAC)

03/03-08/04 UNIV. OF WASHINGTON, Dept. of Atmospheric Sciences Seattle, WA
Research Scientist. Development of instrument package for measuring aerosol optical properties in NEAQS 2004 field campaign.

03/01-03/03 UNIV. OF WASHINGTON, Dept. of Atmospheric Sciences Seattle, WA
Postdoctoral Fellow. Fellowship constituted a continuation of doctoral studies, with participation in an international field campaign (ACE-Asia) and subsequent data analysis and presentation.

12/97-12/98 UNIV. OF WASHINGTON, Dept. of Atmospheric Sciences Seattle, WA
Research Scientist. Responsibilities included instrumental design, development and testing. Assisted in grant-writing.

08/94-10/94 UNIV. OF WYOMING, Dept. of Atmospheric Sciences McMurdo Station, Antarctica
Lab Technician. Responsibilities included preparation, launch, and recovery of balloon-borne instrument packages for research related to the ozone hole. Assisted with data collection and analysis.

10/92-11/93 ANTARCTIC SUPPORT ASSOCIATES McMurdo Station, Antarctica
Science Technician. Responsibilities included running and maintaining a group of thirteen year-round atmospheric experiments. Experimental subjects included: the stratosphere as related to ozone depletion, magnetospheric and ionospheric variations, natural radio wave signal propagation and detection of cosmic rays.

09/88-05/92 ANTARCTIC SUPPORT ASSOCIATES McMurdo Station, Antarctica
Electro-Optical Engineer. Integrated, tested and assisted with design of large-scale adaptive optics systems.

Publications

Fahey, D.W., S. Doherty, K.A. Hibbard, A. Romanou, and P.C. Taylor, 2017: Physical drivers of climate change. In: Climate Science Special Report: Fourth National Climate Assessment, Volume I [Wuebbles, D.J., D.W. Fahey, K.A. Hibbard, D.J. Dokken, B.C. Stewart, and T.K. Maycock (eds.)]. U.S. Global Change Research Program, Washington, DC, USA, pp. 73-113, doi:10.7930/J0513WCR.

Dang, C., S. G. Warren, Q. Fu, S. J. Doherty and M. Sturm, Measurements of light-absorbing particles in snow across the Arctic, North America and china: effects on surface albedo, J. Geophys. Res. - Atmos., doi:10.1022/2017JD027070, 2017.

Doherty, S. J., D. A. Hegg, P. K. Quinn, J. E. Johnson, J. P. Schwarz, C. Dang and S. G. Warren, Causes of variability in light absorption by particles in snow at sites in Idaho and Utah, J. Geophys. Res. - Atmos., 121, doi:10.1002/2015JD024375, 2016.

Tedesco, M., S. J. Doherty, X. Fettweis, P. Alexander and J. Stroeve, The darkening of the Greenland ice sheet: trends, drivers, and projections (1981–2100), The Cryosphere, 10, 477–496, doi:10.5194/tc-10-477-2016, 2016.

Doherty, S. J., M. Steele, I. Rigor and S. G. Warren, Interannual variations of light-absorbing particles in snow on Arctic sea ice, J. Geophys.Res. Atmos., 120, doi:10.1002/2015JD024018, 2015.

Zhang, R., H. Wang, D. A. Hegg, Y. Qian, S. J. Doherty, C. Dang, P.-L. Ma, P. J. Rasch, and Q. Fu, Quantifying sources of black carbon in Western North America using observationally based analysis and an emission tagging technique in the Community Atmosphere Model, Atmos. Chem. Phys., 15, 12805-12822, doi:10.5194/acp-15-12805-2015, 2015.

Tedesco, M., S. Doherty, S. Warren, M. Tranter, J. Stroeve, X. Fettweis, and P. Alexander (2015), What darkens the Greenland Ice Sheet?, Eos, 96, doi:10.1029/2015EO035773. Published on 17 September 2015.

Doherty. S. J., C. Dang, D. A. Hegg, R. Zhang and S. G. Warren, Black carbon and other light- absorbing particles in snow of central North America, J. Geophys. Res. Atmos., 119, doi:10.1002/2014JD022350, 2014.

Qian, Y., T. J. Yasunari, S. J. Doherty, M. Flanner, W. K. M. Lau, J. Ming, H. Wang, M. Wang, S. G. Warren and R. Zhang, Light-absorbing particles in snow and ice: Measurement and modeling of climatic and hydrological impact, Adv. Atmos. Sci., 32 (1), 64-91, doi: 10.1007/s00376-014-0010-0, 2014.

Doherty, S. J., C. M. Bitz, M. G. Flanner, Biases in modeled surface snow BC mixing ratios in prescribed aerosol climate model runs, Atmos. Chem. Phys., 14, 11697-11709, doi: 10.5194/acp-14-11679-2014, 2014.

Bond, T. C., S. J. Doherty, D. W. Fahey, P. M. Forster, T. Berntsen, B. J. DeAngelo, M. G. Flanner, S. Ghan, B. Kärcher, D. Koch, S. Kinne, Y. Kondo, P. K. Quinn, M. C. Sarofim, M. G. Schultz, M. Schulz, C. Venkataraman, H. Zhang, S. Zhang, N. Bellouin, S. K. Guttikunda, P. K. Hopke, M. Z. Jacobon, J. W. Kaiser, Z. Klimont, U. Lohmann, J. P. Schwarz, D. Shindell, T. Storelvmo, S. G. Warren and C. S. Zender, Bounding the Role of Black Carbon in Climate: A scientific assessment, J. Geophys. Res., 118(11), 5380-5552, doi:10.1002/jgrd.50171, 2013.

Doherty, S. J., T. C. Grenfell, S. Forsstrom, D. L. Hegg, S. G. Warren and R. Brandt, Observed vertical redistribution of black carbon and other light-absorbing particles in melting snow, J. Geophys. Res., 118(11), 5553-5569, doi:10.1002/jgrd.50235, 2013.

Wang, X., S. J. Doherty and J. Huang, Black carbon and other light-absorbing impurities in snow across Northern China, J. Geophys. Res., 118 (3), 1471-1492, doi:10.1029/2012JD018291, 2013.

Zatko, M. C., T. C. Grenfell, B. Alexander, S. J. Doherty, J. L. Thomas and X. Yang, The influence of snow grain size and impurities on the vertical profiles of actinic flux and associated NOx emissions on the Antarctic and Greenland ice sheets, Atmos. Chem. Phys. Disc., 12, 15743-15799, 2012.

Schwarz, J. P., S. J. Doherty, G. L. Kok, F. Li, S. T. Ruggiero, C. E. Tanner, A. E. Perring, R. S. Gao and D. W. Fahey, Assessing recent measurement techniques for quantifying black carbon concentration in snow, Aerosol Meas. Tech. Discuss., 5, 2581-2592, doi:10.5194/amt-5-2581-2012, 2012.

Goldenson, N., S. J. Doherty, C. M. Bitz, M. M. Holland, B. Light, and A. J. Conley, Arctic climate response to forcing from light-absorbing particles in snow and sea ice in CESM, Atmos. Chem. Phys., 12, 7903-7920, doi:10.5194/acp-12-7903-2012, 2012.

Hegg, D. A., A. D. Clarke, S. J. Doherty, and J. Strom, Measurements of black carbon aerosol scavenging on Svalbard, Tellus, 63(5), 891-900, doi:10.1111/j.1600-0889.2011.00577.x, 2011.

Wang. Q., D. J. Jacob, J. A. Fisher, J. Mao, E. M. Leibensperger, C. C. Carouge, P. LeSager, Y. Kondo, J. L. Jimenez, M. J. Cubison, and S. J. Doherty, Sources of carbonaceous aerosols and deposited black carbon in the Arctic in winter-spring: implications for radiative forcing, Atmos. Chem Phys., 11, 12,453-12,473, doi:10.5194/acp-11-12453-2011, 2011.

Grenfell, T. C., S. J. Doherty, A. D. Clarke, and S. G. Warren, Spectrophotometric determination of absorptive impurities in snow, Appl. Opt., 50(14), pp.2037-2048, 2011.

Doherty, S. J., S. G. Warren, T. C. Grenfell, A. D. Clarke, R. Brandt, Light-absorbing impurities in Arctic snow, Atmos. Chem. Phys., 10, 11647-11680, doi:10.5294/acp-10-11647-2010, 2010.

Hegg, D. A., S. G. Warren, T. C. Grenfell, S. J. Doherty and A. D. Clarke, Sources of light absorbing aerosol in arctic snow and their seasonal variability, Atmos. Chem. Phys., 10, 10923-10938, doi:10.5194/acp-10-10923-2010, 2010.

Doherty, S. J., P. J. Rasch, and A. R. Ravishankara, A New Initiative: Atmospheric Chemistry & Climate ("AC&C"), EOS, 90(24), 206-207, 16 June 2009.

Hegg, D. A., S. G. Warren, T. C. Grenfell, S. J. Doherty, T. V. Larson, and A. D. Clarke, Source Attribution of Black Carbon in Snow, Env. Sci. Tech., 43(11), 4016-4021, doi: 10.1021/es803623f, 2009.

Doherty, S. J., S. Bojinski, A. Henderson-Sellers, K. Noone, D. Goodrich, N. L. Bindoff, J. A. Church, K. A. Hibbard, T. R. Karl, L. Kajfez-Bogataj, A. H. Lynch, D. E. Parker, I. C. Prentice, V. Ramaswamy, R. W. Saunders, A. J. Simmons, M. Stafford Smith, K. Steffen, T. F. Stocker, P. W. Thorne, K. E. Trenberth, M. M. Verstraete, F. W. Zwiers, Lessons learned from IPCC AR4: Future scientific developments needed to understand, predict and respond to climate change, Bull. Amer. Met. Soc., 90(4), 497-513, 2009.

Fuzzi, S. M. O. Andreae, B. J. Huebert, M. Kulmala, T. C. Bond, M. Boy, S. J. Doherty, A. Guenther, M. Kanakidou, K. Kawamura, V.-M. Kerminen, U. Lohmann, L. M. Russell, U. Poschl, Critical assessment of the current state of scientific knowledge, terminology, and research needs concerning the role of organic aerosols in the atmosphere, climate, and global change, Atmos. Chem. Phys., 6, 2017-2038, 2006.

Yoon, S. C., S. W. Kim, J. Kim, B. J. Sohn, A. Jefferson, S. J. Choi, D. H. Cha, D. K. Lee, T. L. Anderson, S. J. Doherty, R. J. Weber, Enhanced water vapor in Asian dust layer: Entrainment processes and implication for aerosol optical properties, Atmos. Env., 40(13), 2409-2421, 2006.

Doherty, S.J., P. Quinn, A. Jefferson, C. Carrico, T. L. Anderson, D. Hegg, A comparison and summary of aerosol optical properties as observed in-situ from aircraft, ship and land during ACE-Asia, J. Geophys. Res., 110, D04201, doi:10.1029/2004JD004964, 2005.

Kahn, R., J. Anderson, T.L. Anderson, T. Bates., F. Brechtel, C.M. Carrico, A. Clarke, S. Doherty, E. Dutton, R. Flagan, R. Frouin, H. Fukushima, B. Holben, S. Howell, B. Huebert, A. Jefferson, H. Jonsson, O. Kakashnikova, J. Kim, S.-W. Kim, P. Kus, W.-H. Li, J.M. Livingston, C. McNaughton, J. Merrill, S. Mukai, T. Murayama, T. Nakajima, P. Quinn, J. Redemann, M. Rood, P. Russell, I. Sano, B. Schmid, J. Seinfeld, N. Sugimoto, J. Wang, E.J. Welton, J.-G. Won, S.-C. Yoon, Environmental snapshots from ACE-Asia, J. Geophys. Res., 109, D19S14, doi:10.1029/2003JD004339, 2004.

Moore, K. G. I., A. D. Clarke, V. N. Kapustin, C. McNaughton, B. E. Anderson, E. L. Winstead, R. Weber, R., Y. Ma, Y. N. Lee, R. Talbot, J. Dibb, T. Anderson, S. Doherty, D. Covert, and D. Rogers: A comparison of similar aerosol measurements made on the NASA P-3B, DC-8, and NSF C-130 aircraft during TRACE-P and ACE-Asia, J. Geophys. Res., 109, D15S15, doi:10.1029/2003JD003543, 2004.

Tsai, F., T.-H. Liu, S. C. Liu, T.-Y. Chen, T. L. Anderson, and S. J. Masonis, Model simulation and analysis of coarse and fine particle distribution during ACE-Asia, J. Geophys. Res., 109, D19S20, doi:10.1029/2003JD003665, 2004.

Seinfeld, J. H., G. R. Carmichael, R. Arimoto, W. C. Conant, F. J. Brechtel, T. S. Bates, T. A. Cahill, A. D. Clarke, S. J. Doherty, P. J. Flatau, B. J. Huebert, J. Kim, K. M. Markowicz, P. K. Quinn, L. M. Russell, P. B. Russell, A. Shimizu, Y. Shinozuka, C. H. Song, Y. Tang, I. Uno, A. M. Vogelmann, R. J. Weber, J. H. Woo, and X. Y. Zhang, ACE-ASIA: Regional Climatic and Atmospheric Chemical Effects of Asian Dust and Pollution, Bull. Amer. Met. Soc., 85 (3), 367-380, 2004.

Clarke, A. D., Y. Shinozuka, V. N. Kapustin, S. Howell, B. Huebert, S. Doherty, T. Anderson, D. Covert, J. Anderson, X. Hua, K. G. Moore II, C. McNaughton, G. Carmichael, R. Weber, Size distributions and mixtures of dust and black carbon aerosol in Asian outflow: Physiochemistry and optical properties, J. Geophys. Res., 109, D15S09, doi:10.1029/2003JD004378, 2004.

Chin, M., P. Ginoux, R. Lucchesi, B. Huebert, R. Weber, T. Anderson, S. Masonis, B. Blomquist, A. Bandy, and D. Thornton (2003), A global aerosol model forecast for the ACE-Asia field experiment, J. Geophys. Res., 108(D23), 8654, doi:10.1029/2003JD003642, 2003.

Murayama, T., S. J. Masonis, J. Redemann, T. L. Anderson, B. Schmid, J. M. Livingston, P. B. Russell, B. Huebert, S. G. Howell, C. S. McNaughton, A. Clarke, M. Abo, A. Shimizu, N. Sugimoto, M. Yabuki, H. Kuze, S. Fukagawa, K. L. Maxwell, R. J. Weber, D. A. Orsini, B. Blomquist, A. Bandy, and D. Thornton: An intercomparison of lidar-derived aerosol optical properties with airborne measurements near Tokyo during ACE-Asia, J. Geophys. Res., 108 (D23), 8651, doi: 10.1029/2002JD003259, 2003.

Anderson, T. L., S. J. Masonis, D. S. Covert, N. C. Ahlquist, S. G. Howell, A. D. Clarke, C. S. McNaughton: Variability of aerosol optical properties derived from in situ aircraft measurements during ACE-Asia, J. Geophys. Res., 108 (D23), 8647, doi:10.1029/2002JD003247, 2003.

Redemann, J., S. J. Masonis, B. Schmid, T. L. Anderson, P. B. Russell, J. M. Livingston, O. Dubovik, and A. D. Clarke: Clear-column closure studies of aerosol and water vapor aboard the NCAR C-130 in ACE-Asia, 2001, J. Geophys. Res., 108 (D23), 8655, doi: 10.1029/2003JD003442, 2003.

Masonis, S. J., T. L. Anderson, D. S. Covert, V. Kapustin, A. D. Clarke, S. Howell, and K. Moore: A study of the extinction-to-backscatter ratio of marine aerosol during the Shoreline Environment Aerosol Study, J. Atmos. Oceanic Tech., 20(10), 1388-1402, 2003.

Clarke, A., V. Kapustin, S. Howell, K. Moore, B. Leinert, S. Masonis, T. Anderson, and D. Covert: Sea salt size distributions from breaking waves: Implications for marine aerosol production and optical extinction measurements during SEAS, J. Atmos. Oceanic Tech., 20 (10), 1362-1374, 2003.

Masonis, S. J., K. Franke, A. Ansmann, D. Mueller, D. Althausen, J. A. Ogren, A. Jefferson, and P. J. Sheridan: An intercomparison of aerosol light extinction and 180deg backscatter as derived using in-situ instruments and Raman lidar during the INDOEX field campaign, J. Geophys. Res., 107 (D19), 8014, doi: 10.1029/200JD000035, 2002.

Masonis, S. J., and S. G. Warren: Gain of the AVHRR visible channel as tracked using bidirectional reflectance of Antarctic and Greenland snow, Intl. J. Remote Sens., 22, 1495-1520, 2001.

Anderson, T.L., S. J. Masonis, D. S. Covert, R. J. Charlson and M. J. Rood: In situ measurement of the aerosol extinction-to-backscatter ratio at a polluted continental site, J. Geophys. Res., 105 (D22), 26,907-26,915, 2000.

Doherty, S. J., T. L. Anderson and R. J. Charlson: Measurement of the lidar ratio for atmospheric aerosols with a 180-degree backscatter nephelometer, Appl. Optics, 38, 1823-1832, 1999.