PNNL

Andrew Gettelman is a scientist specializing in clouds and climate change. His work concerns the development and analysis of global model simulations of the climate system with a focus on the development of physical parameterizations of clouds in global climate models and the physics and chemistry of the upper troposphere and lower stratosphere. In addition to developing and managing Earth system models, Gettelman is involved in model evaluation data analysis with satellites and field programs and has served on science teams for both satellite and field projects. Gettelman has been a visiting professor in Physics in Oxford, an Erskine visiting fellow at the University of Canterbury in Christchurch, New Zealand, and a visiting professor in the Institute for Atmospheric and Climate Science at the Swiss Federal Institute of Technology in Zürich, Switzerland. Gettelman came to Pacific Northwest National Laboratory after being a senior scientist at the National Center for Atmospheric Research. Gettelman is the author or co-author on over 200 peer reviewed publications and a textbook (Demystifying Climate Models, Springer). Gettelman has a PhD in atmospheric sciences from the University of Washington and a BS in civil engineering from Princeton University. Click to view Andrew Gettelman's full CV here.

• Clouds and climate change
• Aerosol-cloud interactions
• Climate model development and app

• PhD in Atmospheric Sciences, University of Washington
• BE in Civil Engineering, Princeton University

• Editor, Reviews of Geophysics, 2022 – Present
• Co-Chair, World Climate Research Programme Digital Earth Lighthouse Activity, 2022 – Present
• Science Board Member, Atmospheric Radiation Measurement Climate Research Facility, 2020 – 2021
• Coordinator, Aerosols, Clouds Precipitation and Climate Shallow Clouds Working Group under the World Climate Research Programme and International Geosphere-Biosphere Programme, 2019 – Present
• Science Coordinating Committee Member, NASA Aerosol, Clouds, Convection and Precipitation Study, 2017 – 2021
• Member, National Academy of Sciences Panel, Opportunities to Improve the Representation of Clouds and Aerosols in Climate Models with Classified Observing Systems, 2015 – 2016
• User Executive Committee Member, Department of Energy Atmospheric System Research, 2015 – 2019
• Steering Committee, SPARC-IGAC Chemistry Climate Model Initiative, 2012 – 2019
• Steering Committee, SPARC-IGAC Atmospheric Chemistry and Climate Initiative, 2007 – 2012
• Co-Coordinator, SPARC Chemistry-Climate Model Validation Project, 2005 – 2012
• Contributing Author, Chapter 6, World Meteorological Organization Ozone Assessment, 2006
• Communications Secretary, American Geophysical Union Atmospheric Sciences Section, 2003 – 2006

• Fellow, American Geophysical Union, 2022
• Highly Cited Paper Award, J. Advances in Modeling Earth Systems, 2022
• National Center for Atmospheric Research Director’s Special Recognition Award: Development and Leadership of the System for Integrated Modeling of the Atmosphere, 2022
• Top Cited Article, Geophysical Research Letters, 2019 – 2020
• Group Achievement Award for ATTREX Project, NASA, 2016
• Ascent Award, American Geophysical Union, 2015
• Member, National Academy of Sciences Panel, Opportunities to Improve the Representation of Clouds and Aerosols in Climate Models with Classified Observing Systems, 2015 – 2016
• Thompson Reuters Highly Cited Researcher, 2014 – 2022
• Editor’s Award, Journal of the Atmospheric Sciences, 2004

2025

• Gettelman A., C. Tebaldi, and L. Leung. 2025. "Climate Nowcasting." Environmental Research: Climate 4, no. 1:013002. PNNL-SA-205270. doi:10.1088/2752-5295/adc327
• Mikkelsen A., D.T. Mccoy, T. Eidhammer, A. Gettelman, C. Song, H. Gordon, and I.T. McCoy. 2025. "Constraining Aerosol-Cloud Adjustments by Uniting Surface Observations with a Perturbed Parameter Ensemble." Atmospheric Chemistry and Physics 25, no. 8:4547 - 4570. PNNL-SA-201337. doi:10.5194/acp-25-4547-2025
• Yin Z., A.R. Herrington, R.T. Datta, A. Subramanian, J. Lenaerts, and A. Gettelman. 2025. "Improved Understanding of Multicentury Greenland Ice Sheet Response to Strong Warming in the Coupled CESM2-CISM2 with Regional Grid Refinement." Journal of Advances in Modeling Earth Systems 17, no. 2:Art No. e2024MS004310. PNNL-SA-208487. doi:10.1029/2024MS004310
• Zeng X., L.R. Alves, M. Boucher, A. Cherchi, C. Demott, A. Dimri, and A. Gettelman, et al. 2025. "Global Precipitation Experiment - A New World Climate Research Programme Lighthouse Activity." Bulletin of American Meteorological Society 106, no. 2:E408-E418. PNNL-SA-198009. doi:10.1175/BAMS-D-23-0242.1
• Zhang W., K. Van Weverberg, C.J. Morcrette, W. Feng, K. Furtado, P. Field, and C. Chen, et al. 2025. "Impact of host climate model on contrail cirrus effective radiative forcing estimates." Atmospheric Chemistry and Physics 25, no. 1:473-489. PNNL-SA-212671. doi:10.5194/acp-25-473-2025
• Zhou X., D. Painemal, A. Gettelman, and G. Feingold. 2025. "Exploring causal relationships and adjustment timescales of aerosol-cloud interactions in geostationary satellite observations and CAM6 using wavelet phase coherence analysis." Geophysical Research Letters 52, no. 2:Art No. e2024GL111961. PNNL-SA-203056. doi:10.1029/2024GL111961

2024

• Cohen S.P., A.H. Sobel, M. Biasutti, S. Wang, I. Simpson, A. Gettelman, and I. Hu. 2024. "Implementation and Exploration of Parameterizations of Large-Scale Dynamics in NCAR's Single Column Atmosphere Model SCAM6." Journal of Advances in Modeling Earth Systems 16, no. 6:Art. No. e2023MS003866. PNNL-SA-202387. doi:10.1029/2023MS003866
• Duffy M., B. Medeiros, A. Gettelman, and T. Eidhammer. 2024. "Perturbing parameters to understand cloud contributions to climate change." Journal of Climate 37, no. 1:213-227. PNNL-SA-192050. doi:10.1175/JCLI-D-23-0250.1
• Eidhammer T., A. Gettelman, K. Thayer-Calder, D. Watson-Parris, G. Elsaesser, H. Morrison, and M.V. Lier-Walqui, et al. 2024. "An Extensible Perturbed Parameter Ensemble for the Community Atmosphere Model Version 6." Geoscientific Model Development 17, no. 21:7835-7853. PNNL-SA-190726. doi:10.5194/gmd-17-7835-2024
• Feingold G., V.P. Ghate, L. Russell, P.N. Blossey, W. Cantrell, M. Christensen, and M.S. Diamond, et al. 2024. "Physical science research needed to evaluate the viability and risks of marine cloud brightening." Science Advances 10, no. 12:Art. No. eadi8594. PNNL-SA-189954. doi:10.1126/sciadv.adi8594
• Forster P., C.J. Smith, T. Walsh, W.F. Lamb, R. Lamboll, B. Hall, and M. Hauser, et al. 2024. "Indicators of Global Climate Change 2023: annual update of key indicators of the state of the climate system and human influence." Earth System Science Data 16, no. 6:2625-2658. PNNL-SA-198099. doi:10.5194/essd-16-2625-2024
• Gettelman A., M. Christensen, M.S. Diamond, E. Gryspeerdt, P. Manshausen, P. Stier, and D. Watson-Parris, et al. 2024. "Has Reducing Ship Emissions Brought Forward Global Warming?." Geophysical Research Letters 51, no. 15:Art. No. e2024GL109077. PNNL-SA-196069. doi:10.1029/2024GL109077
• Gettelman A., R. Forbes, R. Marchand, C. Chen, and M. Fielding. 2024. "The Impact of Cloud Microphysics and Ice Nucleation on Southern Ocean Clouds assessed with single-column modeling and instrument simulators." Geoscientific Model Development 17, no. 21:8069-8092. PNNL-SA-195594. doi:10.5194/gmd-17-8069-2024
• Gettelman A., T. Eidhammer, M. Duffy, D.T. Mccoy, C. Song, and D. Watson-Parris. 2024. "The Interaction Between Climate Forcing and Feedbacks." Journal of Geophysical Research: Atmospheres 129, no. 18:Art No. e2024JD040857. PNNL-SA-194295. doi:10.1029/2024JD040857
• Huang X., A. Gettelman, B. Medeiros, and W. Skamarock. 2024. "Examining Tropical Convection Features at Storm-Resolving Scales Over the Maritime Continent Region." Journal of Geophysical Research: Atmospheres 129, no. 20:e2024JD040976. PNNL-SA-208227. doi:10.1029/2024JD040976
• Muelmenstaedt J.H., A. Ackerman, A. Fridlind, M. Huang, P. Ma, N.G. Mahfouz, and S.E. Bauer, et al. 2024. "Can general circulation models (GCMs) represent cloud liquid water path adjustments to aerosol-cloud interactions?." Atmospheric Chemistry and Physics 24, no. 23:13633-13652. PNNL-SA-197852. doi:10.5194/acp-24-13633-2024
• Muelmenstaedt J.H., E. Gryspeerdt, S. Dipu, J. Quaas, A. Ackerman, A. Fridlind, and F. Tornow, et al. 2024. "General circulation models simulate negative liquid water path--droplet number correlations, but anthropogenic aerosols still increase simulated liquid water path." Atmospheric Chemistry and Physics 24, no. 12:7331-7345. PNNL-SA-193973. doi:10.5194/acp-24-7331-2024
• Raghuraman S.P., B. Medeiros, and A. Gettelman. 2024. "Observational Quantification of Tropical High Cloud Changes and Feedbacks." Journal of Geophysical Research: Atmospheres 129, no. 7:Art. No. e2023JD039364. PNNL-SA-201540. doi:10.1029/2023JD039364
• Song C., D.T. Mccoy, T. Eidhammer, A. Gettelman, I.T. Mccoy, D. Watson-Parris, and C.J. Wall, et al. 2024. "Buffering of Aerosol-Cloud Adjustments by Coupling Between Radiative Susceptibility and Precipitation Efficiency." Geophysical Research Letters 51, no. 11:Art. No. e2024GL108663. PNNL-SA-201152. doi:10.1029/2024GL108663
• Stammer D., D. Amrhein, M.A. Balmaseda, L. Bertino, M. Bonavita, C. Buontempo, and N. Caltabiano, et al. 2024. "Earth system reanalysis in support of climate model improvements." Bulletin of American Meteorological Society 105, no. 8:E1399-E1406. PNNL-SA-198975. doi:10.1175/BAMS-D-24-0110.1

2023

• Davis N.A., D. Visioni, R.R. Garcia, D.E. Kinnison, D.R. Marsh, M. Mills, and J. Richter, et al. 2023. "Climate, Variability, and Climate Sensitivity of "Middle Atmosphere" Chemistry Configurations of the Community Earth System Model Version 2, Whole Atmosphere Community Climate Model Version 6 (CESM2(WACCM6))." Journal of Advances in Modeling Earth Systems 15, no. 9:Art. No. e2022MS003579. PNNL-SA-192611. doi:10.1029/2022MS003579
• Florindo F., V. Acocella, A.G. Carlton, P. D'odorico, Q. Duan, A. Gettelman, and J. Halekas, et al. 2023. "60 Years and Beyond of Reviews of Geophysics." Reviews of Geophysics 61, no. 2:e2023RG000807. PNNL-SA-190679. doi:10.1029/2023RG000807
• Gettelman A. 2023. "Rainbows and Climate Change: A tutorial on climate model diagnostics and parameterization." Geoscientific Model Development 16, no. 17:4937-4956. PNNL-SA-181861. doi:10.5194/egusphere-2023-227
• Jakob C., A. Gettelman, and A.J. Pitman. 2023. "The need to operationalize climate modelling." Nature Climate Change 13, no. 11:1158-1160. PNNL-SA-190788. doi:10.1038/s41558-023-01849-4
• Mcgraw Z., T. Storelvmo, L.M. Polvani, S. Hofer, J.K. Shaw, and A. Gettelman. 2023. "On the Links Between Ice Nucleation, Cloud Phase, and Climate Sensitivity in CESM2." Geophysical Research Letters 50, no. 17:Art. No. e2023GL105053. PNNL-SA-192592. doi:10.1029/2023GL105053
• Neelin D., J.P. Krasting, A. Radhakrishnan, J. Liptak, T. Jackson, Y. Ming, and W. Dong, et al. 2023. "Process-Oriented Diagnostics Principles, Practice, Community Development, and Common Standards." Bulletin of American Meteorological Society 104, no. 8:E1452-E1468. PNNL-SA-192598. doi:10.1175/BAMS-D-21-0268.1
• Sun J., J. Dennis, S. Mickelson, B.J. Vanderwende, A. Gettelman, and K. Thayer-Calder. 2023. "Acceleration of the Parameterization of Unified Microphysics Across Scales (PUMAS) on the Graphics Processing Unit (GPU) With Directive-Based Methods." Journal of Advances in Modeling Earth Systems 15, no. 5:Art. No. e2022MS003515. PNNL-SA-192584. doi:10.1029/2022MS003515

2022

• Huang, Xingying, Andrew Gettelman, William C. Skamarock, Peter Hjort Lauritzen, Miles Curry, Adam Herrington, John T. Truesdale, and Michael Duda. 2022. “Advancing precipitation prediction using a new-generation storm-resolving model framework – SIMA-MPAS (V1.0): a case study over the western United States,” Geosci. Model Dev., 15, 8135–8151. doi: 10.5194/gmd-15-8135-2022
• A. Herrington, P. Lauritzen, W. Lipscomb, M. Lofverstrom, A. Gettelman and M. Taylor. 2022. “Impact of grids and dynamical cores in CESM2.2 on the surface mass balance of the Greenland Ice Sheet,” J. Advances Modeling Earth Systems. doi: 10.1029/2022MS003192
• Järvinen, Emma, Christina S. McCluskey, Fritz Waitz, Martin Schnaiter, Aaron Bansemer, Charles G. Bardeen, Andrew Gettelman, et al. 2022. “Evidence for Secondary Ice Production in Southern Ocean Maritime Boundary Layer Clouds.” Journal of Geophysical Research: Atmospheres, 127 (16), e2021JD036411. https://doi.org/10.1029/2021JD036411.
• Stephens, Graeme L., Maria Z. Hakuba, Seiji Kato, Andrew Gettleman, Jean-Louis Dufresne, Timothy Andrews, Jason N. S. Cole, Ulrika Willem, and Thorsten Mauritsen. 2022. “The Changing Nature of Earth’s Reflected Sunlight.” Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 478 (2263), 20220053.https://doi.org/10.1098/rspa.2022.0053.
• Hu, I-Kuan, Brian E. Mapes, Stefan N. Tulich, Richard B. Neale, Andrew Gettelman, and Kevin A. Reed. 2022. “Idealized Simulations of the Tropical Climate and Variability in the Single Column Atmosphere Model (SCAM): Radiative-Convective Equilibrium,” Journal of Advances in Modeling Earth Systems, 14 (2), e2021MS002826. https://doi.org/10.1029/2021MS002826.
• Harrop, Bryce E., Michael S. Pritchard, Hossein Parishani, Andrew Gettelman, Samson Hagos, Peter H. Lauritzen, L. Ruby Leung, Jian Lu, Kyle G. Pressel, and Koichi Sakaguchi. 2022. “Conservation of Dry Air, Water, and Energy in CAM and Its Potential Impact on Tropical Rainfall.” Journal of Climate, 35 (9), 2895–2917. https://doi.org/10.1175/JCLI-D-21-0512.1.
• Ma, Po-Lun, Bryce E. Harrop, Vincent E. Larson, Richard B. Neale, Andrew Gettelman, Hugh Morrison, Hailong Wang, et al. 2022. “Better Calibration of Cloud Parameterizations and Subgrid Effects Increases the Fidelity of the E3SM Atmosphere Model Version 1.” Geoscientific Model Development, 15(7), 2881–2916. https://doi.org/10.5194/gmd-15-2881-2022.
• Gettelman, Andrew, Alan J. Geer, Richard M. Forbes, Greg R. Carmichael, Graham Feingold, Derek J. Posselt, Graeme L. Stephens, Susan C. van den Heever, Adam C. Varble, and Paquita Zuidema. 2022. “The Future of Earth System Prediction: Advances in Model-Data Fusion.” Science Advances, 8 (14), eabn3488. https://doi.org/10.1126/sciadv.abn3488.