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Stephen Po-Chedley

Portrait of  Stephen Po-Chedley

  • Title
    Research Scientist
  • Email
    pochedley1@llnl.gov
  • Phone
    (925) 422-3421

Research Interests

I am a climate scientist working to better understand past and future changes in climate. To understand past changes in climate, I work with satellite records dating back to the late 1970s  to measure how much the Earth's atmosphere has warmed. I also work with climate models to predict future changes in climate. While I am largely focused on the physical climate system and understanding the Earth's sensitivity to greenhouse gases, I am also interested in understanding the effects of climate change on food security and human health.

Appointments

  • Research Scientist, PCMDI | Lawrence Livermore National Laboratory, 2020 - present
  • Postdoctoral Fellow, PCMDI | Lawrence Livermore National Laboratory, 2017 - 2020
  • Graduate Fellow, Department of Atmospheric Sciences | University of Washington, Seattle, 2014 - 2016
  • Medical Informatics Officer, Abwenzi Pa Za Umoyo / Partners In Health, Malawi, 2013 - 2014
  • Graduate Fellow, Department of Atmospheric Sciences | University of Washington, 2009 - 2013
  • Minerva Fellow, Engeye Health, Uganda, 2008 - 2009

Ph.D. in Atmospheric Sciences, University of Washington, Seattle, WA, 2016

M.S. in Atmospheric Sciences, University of Washington, Seattle, WA, 2013

B.S. in Physics, Union College, Schenectady, NY, 2008

2021

  • Po-Chedley, S., B. D. Santer, S. Fueglistaler, M. D. Zelinka, P. J. Cameron-Smith, J. F. Painter, Q. Fu, 2021: "Natural variability contributes to model-satellite differences in tropical tropospheric warming," Proceedings of the National Academy of Sciences, 118 (13) e2020962118; doi: 10.1073/pnas.2020962118.
  • Santer, B. D., S. Po-Chedley, C. A. Mears, et al., 2021: "Using Climate Model Simulations to Constrain Observations," Journal of Climate, submitted. 

2020

  • Feldl, N., S. Po-Chedley, H. Singh, S. Hay, and P. Kushner, 2020: "Sea ice and atmospheric circulation shape the high-latitude lapse rate feedback," npj Climate and Atmospheric Sciences, in press.
  • Rieger, L. A., J. N. S. Cole, J. C. Fyfe, S. Po-Chedley, P. J. Cameron-Smith, P. J. Durack, N. P. Gillett, and Q. Tang, 2020: "Quantifying CanESM5 and EAMv1 sensitivities to volcanic forcingfor the CMIP6 historical experiment," Geosci. Model Dev. Discuss., doi: 10.5194/gmd-13-4831-2020.
  • Zelinka, M. D., Myers, T. A., McCoy, D. T., Po-Chedley, S., Caldwell, P. M., Ceppi, P., et al, 2020: "Causes of higher climate sensitivity in CMIP6 models," Geophys. Res. Lett.47, e2019GL085782, doi: 10.1029/2019GL085782[EOS]

2019

  • Santer, B. D., and Coauthors, 2019: Celebrating the anniversary of three key events in climate change science. Nature Climate Change, 9 (3), 180–182, doi:10.1038/s41558-019-0424-x.
  • Siler, N., C. Proistosescu, and S. Po-Chedley, 2019: Natural Variability Has Slowed the Decline in Western U.S. Snowpack Since the 1980s. Geophysical Research Letters, 46 (1), 346–355, doi:10.1029/2018GL081080.

2018

  • Po-Chedley, S., C. Proistosescu, K. C. Armour, and B. D. Santer, 2018: Climate constraint reflects forced signal. Nature, 563 (7729), E6–E9, doi:10.1038/s41586-018-0640-y.
  • Christy, J. R., C. A. Mears, and S. Po-Chedley, 2018: Global Climate: Tropospheric Temperature [in “State of the Climate in 2017”]. Bulletin of the American Meteorological Society, 99 (8), S16 – S18.
  • Santer, B. D., and Coauthors, 2018: Human influence on the seasonal cycle of tropospheric temperature. Science, 361 (6399), eaas8806, doi:10.1126/science.aas8806.
  • Ding, Q., and Coauthors, 2018: Fingerprints of internal drivers of Arctic sea ice loss in observations and model simulations. Nature Geoscience, doi:10.1038/s41561-018-0256-8.
  • Siler, N., S. Po-Chedley, and C. S. Bretherton, 2018: Variability in modeled cloud feedback tied to differences in the climatological spatial pattern of clouds. Climate Dynamics, 50 (3-4), 1209–1220, doi:10.1007/s00382-017-3673-2.
  • Po-Chedley, S., K. Armour, C. Bitz, M. Zelinka, and B. Santer, 2018: Sources of intermodel spread in the lapse rate and water vapor feedbacks. Journal of Climate, 31 (8), doi:10.1175/JCLI-D-17-0674.1.

2017

  • Bilinski, A., and Coauthors, 2017: Distance to care, enrollment and loss to follow-up of HIV patients during decentralization of antiretroviral therapy in Neno District, Malawi: A retrospective cohort study. PLOS ONE, 12 (10), e0185 699, doi:10.1371/journal.pone.0185699.
  • Santer, B., S. Solomon, F. Wentz, Q. Fu, S. Po-Chedley, C. Mears, J. Painter, and C. Bonfils, 2017: Tropospheric Warming over the Past Two Decades. Scientific Reports, 7 (1), doi:10.1038/s41598-017-02520-7.
  • Santer, B., and Coauthors, 2017: Causes of differences in model and satellite tropospheric warming rates. Nature Geoscience, 10 (7), doi: 10.1038/ngeo2973.
  • Ding, Q., and Coauthors, 2017: Influence of high-latitude atmospheric circulation changes on summertime Arctic sea ice. Nature Climate Change, 7 (4), doi:10.1038/nclimate3241.
  • Santer, B. D., and Coauthors, 2017: Comparing Tropospheric Warming in Climate Models and Satellite Data. Journal of Climate, 30 (1), 373–392, doi:10.1175/JCLI-D-16-0333.1.

2015

  • Po-Chedley, S., T. J. Thorsen, and Q. Fu, 2015: Removing Diurnal Cycle Contamination in Satellite-Derived Tropospheric Temperatures: Understanding Tropical Tropospheric Trend Discrepancies. Journal of Climate, 28 (6), 2274–2290, doi:10.1175/JCLI-D-13-00767.1.

2014

  • Flannaghan, T. J., S. Fueglistaler, I. M. Held, S. Po-Chedley, B. Wyman, and M. Zhao, 2014: Tropical Temperature Trends in AMIP Simulations and the Impact of SST Uncertainties. Journal of Geophysical Research — Atmospheres, 119, doi:10.1002/2014JD022365.

2013

  • Po-Chedley, S., and Q. Fu, 2013: Reply to ”Comments on ’A Bias in the Midtropospheric Channel Warm Target Factor on the NOAA-9 Microwave Sounding Unit”’ Journal of Atmospheric and Oceanic Technology, 30 (5), doi:10.1175/JTECH-D-12-00131.1.

2012

  • Po-Chedley, S., and Q. Fu, 2012: A Bias in the Midtropospheric Channel Warm Target Factor on the NOAA-9 Microwave Sounding Unit. Journal of Atmospheric and Oceanic Technology, 29 (5), doi:10.1175/JTECH-D-11-00147.1.
  • Po-Chedley, S., and Q. Fu, 2012: Discrepancies in tropical upper tropospheric warming between atmospheric circulation models and satellites. Environmental Research Letters, 7, 044 018, doi:10.1088/1748-9326/7/4/044018.

2007

  • Po-Chedley, S., B. Cohen, and M. Hagerman, 2007: Fast, ultrasensitive virus detection using a young interferometer sensor. Chemtracts, 19 (9), 350 - 357.
  • Lawrence Postdoctoral Fellowship, Lawrence Livermore National Laboratory, 2017 - 2020
  • Lawrence Livermore National Laboratory Outstanding Postdoctoral Fellow, 2020
  • National Science Foundation Atmospheric and Geospace Sciences Postdoctoral Fellowship, Lawrence Livermore National Laboratory, 2017
  • National Science Foundation IGERT Trainee in Ocean Change, University of Washington, 2014 - 2016
  • National Science Foundation Graduate Research Fellowship, University of Washington, 2010 - 2013
  • Minerva Fellow, Union College, 2008 - 2009
  • Frank Bailey Prize for “the Senior who has rendered the greatest service to the college,” Union College, 2008
  • Meritorious Service Award for "service beyond the normal requirement of duty," Union College, 2008
  • Udall Scholar, Udall Foundation, 2006
  • New York State Regents Scholar and Union College Presidential Scholar, 2004