Dr. Andrew T. Wittenberg

Research Interests

• El Niño and climate change
• coupled ocean/atmosphere interactions in the tropics
• multivariate analysis, statistical/dynamical modeling
• development of coupled general circulation models and intermediate-complexity models
• seasonal-to-interannual forecasting and predictability
• ocean data assimilation
• dynamical systems

Education

Professional Experience

Peer-Reviewed Publications

1. Vecchi, G. A., and A. T. Wittenberg, 2009: El Niño and our future climate: Where do we stand?   Wiley Interdisciplinary Reviews: Climate Change, in press, November 2009.
2. Kug, J.-S., J. Choi, S.-I. An, F.-F. Jin, and A. T. Wittenberg, 2009: Warm pool and cold tongue El Niño events as simulated by the GFDL CM2.1 coupled GCM.  J. Climate, accepted October 2009.
3. Xie, S.-P., C. Deser, G. A. Vecchi, J. Ma, H. Teng, and A. T. Wittenberg, 2009: Global warming pattern formation: Sea surface temperature and rainfall.  J. Climate, 23, 966-986.
4. Stenchikov, G, T. L. Delworth, V. Ramaswamy, R. J. Stouffer, A. Wittenberg, and F. Zeng, 2009: Volcanic signals in oceans.  J. Geophys. Res., 114, D16104, doi:10.1029/2008JD011673.
5. Wittenberg, A. T., 2009: Are historical records sufficient to constrain ENSO simulations?  Geophys. Res. Lett., 36, L12702.  doi:10.1029/2009GL038710.
6. Anderson, W., A. Gnanadesikan, and A. Wittenberg, 2009: Regional impacts of ocean color on tropical Pacific variability.  Ocean Sci., 5, 313-327.
7. Guilyardi, E., A. Wittenberg, A. Fedorov, M. Collins, C. Wang, A. Capotondi, G. J. van Oldenborgh, and T. Stockdale, 2009: Understanding El Niño in ocean-atmosphere general circulation models: Progress and challenges.  Bull. Amer. Meteor. Soc., 90, 325-340.  doi:10.1175/2008BAMS2387.1
8. Sukharev, J., C. Wang, K.-L. Ma, and A. T. Wittenberg, 2009: Correlation study of time-varying multivariate climate data sets.   Proc. of IEEE VGTC Pacific Visualization Symposium 2009, Beijing, China, April 2009. Video (AVI, 22MB).
9. Zavala-Garay, J., C. Zhang, A. M. Moore, A. T. Wittenberg, M. J. Harrison, A. Rosati, J. Vialard, and R. Kleeman, 2008: Sensitivity of hybrid ENSO models to unresolved atmospheric variability.  J. Climate, 21, 3704-3721.  doi:10.1175/2007JCLI1188.1
10. Kim, D., J.-S. Kug, I.-S. Kang, F.-F. Jin, and A. T. Wittenberg, 2008: Tropical Pacific impacts of convective momentum transport in the SNU coupled GCM.  Climate Dyn., 31, 213-226.  doi:10.1007/s00382-007-0348-4.
11. Gebbie, G., I. Eisenman, A. Wittenberg, and E. Tziperman, 2007: Could ocean-modulated wind bursts lead to better El Niño forecasts?  Bull. Amer. Meteor. Soc., 88 (9), 1356-1357.
12. Gebbie, G., I. Eisenman, A. Wittenberg, and E. Tziperman, 2007: Modulation of westerly wind bursts by sea surface temperature: A semistochastic feedback for ENSO.  J. Atmos. Sci., 64, 3281-3295.
13. Zhang, S., M. J. Harrison, A. Rosati, and A. Wittenberg, 2007: System design and evaluation of coupled ensemble data assimilation for global oceanic climate studies.  Mon. Wea. Rev., 135, 3541-3564.  Winner of the 2008 NOAA Research Outstanding Scientific Paper Award.
14. Sun, C., M. M. Rienecker, A. Rosati, M. Harrison, A. Wittenberg, C. L. Keppenne, J. P. Jacob, and R. M. Kovach, 2007: Comparison and sensitivity of ODASI ocean analyses in the tropical Pacific.  Mon. Wea. Rev., 135, 2242-2264.
15. Vecchi, G. A., B. J. Soden, A. T. Wittenberg, I. M. Held, A. Leetmaa, and M. J. Harrison, 2006: Weakening of tropical Pacific atmospheric circulation due to anthropogenic forcing.  Nature, 441, 73-76.  doi:10.1038/nature04744. See full text and supplementals.   Winner of the 2007 NOAA Research Outstanding Scientific Paper Award.
16. Capotondi, A., A. Wittenberg, and S Masina, 2006: Spatial and temporal structure of tropical Pacific interannual variability in 20th century coupled simulations.  Ocean Modelling, 15, 274-298.
17. Wittenberg, A. T., A. Rosati, N.-C. Lau, and J. J. Ploshay, 2006: GFDL's CM2 global coupled climate models.  Part III: Tropical Pacific climate and ENSO.  J. Climate, 19, 698-722.
18. Gnanadesikan et al., 2006: GFDL's CM2 global coupled climate models, Part II: The baseline ocean simulation.  J. Climate, 19, 675-697.
19. Delworth et al., 2006: GFDL's CM2 global coupled climate models, Part I: Formulation and simulation characteristics.  J. Climate, 19, 643-674.
20. Vecchi, G. A., A. T. Wittenberg, and A. Rosati, 2006: Reassessing the role of stochastic forcing in the 1997-8 El Niño.  Geophys. Res. Lett., 33, L01706.  doi:10.1029/2005GL024738.
21. Zhang, S., M. J. Harrison, A. T. Wittenberg, A. Rosati, J. L. Anderson, and V. Balaji, 2005: Initialization of an ENSO forecast system using a parallelized ensemble filter.   Mon. Wea. Rev., 133, 3176-3201.
22. The GFDL Global Atmospheric Model Development Team, 2004: The new GFDL global atmosphere and land model AM2/LM2: Evaluation with prescribed SST simulations.  J. Climate, 17, 4641-4673.
23. Wittenberg, A. T., 2004: Extended wind stress analyses for ENSO.  J. Climate, 17, 2526-2540.
24. Zhang, S., J. L. Anderson, A. Rosati, M. Harrison, S. P. Khare, and A. T. Wittenberg, 2004: Multiple time level adjustment for data assimilation. Tellus A, 56, 2-15.
25. Fedorov, A. V. , S. L. Harper, S. G. Philander,  B. Winter, and A. Wittenberg, 2003: How predictable is El Nino?  Bull. Amer. Meteor. Soc., 84, 911-919.
26. Wittenberg, A. T., 2002: ENSO response to altered climates.  Ph.D. thesis, Princeton University. 475pp.
27. Wittenberg, A. T., and J. L. Anderson, 1998: Dynamical implications of prescribing part of a coupled system: Results from a low-order model.  Nonlin. Proc. Geophys., 5, 167-179.
28. Hartmann, W. M., and A. Wittenberg, 1996: On the externalization of sound images.  J. Acoust. Soc. Am., 99, 3678-3688.

Works submitted

1. Collins, M., S.-I. An, W. Cai, A. Ganachaud, E. Guilyardi, F.-F. Jin, M. Jochum, M. Lengaigne, S. Power, A. Timmermann, G. Vecchi, and A. Wittenberg, 2010: The impact of global warming on the tropical Pacific and El Niño.  Submitted to Nature Geoscience, December 2009.

Talks

1. Wittenberg, A. T., T. Rosati, S. Zhang, et al., 2009: Seasonal to decadal predictability.  Roundtable on Applying Models of Global Climate Change to Natural Resources Management, NOAA/GFDL, Princeton, NJ, 17 August 2009.
2. Wittenberg, A. T., 2009: Climate change and ENSO.  GFDL External Review, NOAA/GFDL, Princeton, NJ, 1 July 2009.
3. Wittenberg, A. T., 2009: CM3: Tropical climate and ENSO.  GFDL-NCAR Atmospheric GCM Meeting, NOAA/GFDL, Princeton, NJ, 27 April 2009.
4. Wittenberg, A. T., W. Anderson, A. Gnanadesikan, A. Capotondi, and G. Vecchi, 2009: Understanding & simulating El Niño: Lessons from the GFDL coupled GCMs.
   • Bureau of Meteorology (CAWCR), Melbourne, Australia, 31 March 2009.
   • CSIRO Marine Laboratories, Hobart, Tasmania, 3 April 2009.
5. Wittenberg, A. T., 2009: CO2-induced changes in tropical climate, as simulated by the GFDL coupled GCMs.  International ENSO Workshop, Greenhouse 2009, Perth, Australia, 26 March 2009. See page 31 of the workshop report.
6. Wittenberg, A. T., 2008: Natural and forced modulation of ENSO in the GFDL CM2.1 coupled GCM.  Department of Atmospheric & Oceanic Science, University of Maryland, College Park, MD, 2 October 2008.
7. Wittenberg, A. T., 2008: Natural modulation of ENSO in the GFDL CM2.1 coupled GCM.
   • EGU General Assembly, Vienna, Austria, 15 April 2008.
   • 13th Annual CCSM Workshop, Breckenridge, CO, 19 June 2008.
8. Wittenberg, A. T., K. Eckerle, G. Vecchi, S. Song, and A. Rosati, 2008: Indonesian Throughflow transports, variability, and change in the GFDL coupled GCMs.  INSTANT Workshop, Lamont-Doherty Earth Observatory, Palisades, NY, 29 May 2008.
9. Wittenberg, A. T., and M. Winton, 2008: Coupled climate modeling at GFDL.  NOAA Climate Working Group, Climate Research and Modeling (CRM) Program Review, Hyatt Regency, Princeton, NJ, 25 March 2008.
10. Wittenberg, A. T., 2006: ENSO dynamics and predictability in the GFDL coupled models.  Workshop on ENSO Dynamics and Predictability, Seoul National University, Seoul, South Korea, 12 September 2006. Also in OpenOffice.
11. Wittenberg, A. T., and A. Rosati, 2006: What controls the period and amplitude of ENSO?  11th Annual CCSM Workshop, Breckenridge, CO, 20 June 2006.
12. Wittenberg, A. T., G. A. Vecchi, and A. Rosati, 2006: Reassessing the role of stochastic forcing in the 1997-8 El Niño.  AGU Joint Assembly, Baltimore, MD, 25 May 2006.
13. Vecchi, G. A., B. Soden, I. Held, A. Wittenberg, A. Leetmaa, and M. Harrison, 2006: Weakening of the Pacific Walker Circulation since the mid-19th Century.  AGU Joint Assembly, Baltimore, MD, 26 May 2006.
14. Vecchi, G., Q. Song, A. Wittenberg, and M. Harrison, 2006: Coupled Indian Ocean intraseasonal variability.  AGU Joint Assembly, Baltimore, MD, 25 May 2006.
15. Wittenberg, A. T., 2006: Simulated CO2-induced changes in tropical climate and variability.  NOAA Geophysical Fluid Dynamics Laboratory, Princeton, NJ, 22 March 2006.
16. Eisenman, I., E. Tziperman, J. Gebbie, L. Yu, and A. Wittenberg, 2005: Feedbacks between El Nino and the "noise" that drives it: Modulation of westerly wind bursts by large-scale SST.  Boston University, 17 October 2005.
17. Wittenberg, A. T., 2005: Climate sensitivities of ENSO: Bridging theories, observations, and modeling.  First Alexander von Humboldt International Conference on The El Niño Phenomenon and Its Global Impact, Guayaquil, Ecuador, 20 May 2005. Also in OpenOffice and PowerPoint. The abstract is here.
18. Gebbie, G., I. Eisenman, E. Tziperman, and A. Wittenberg, 2005: Westerly wind bursts: ENSO's tail rather than dog?  EGU General Assembly, Vienna, Austria, 28 April 2005. Also in OpenOffice and PowerPoint. The abstract is here.
19. Wittenberg, A. T., 2005: On extended wind stress analyses for ENSO.   Stony Brook University, Stony Brook, New York, 2 February 2005. Also in PowerPoint.
20. Wittenberg, A. T., G. Vecchi, T. Rosati, M. Harrison, I. Held, and T. Knutson, 2005: ENSO Modeling at GFDL.   Overview for Rick Rosen (Assistant Administrator, NOAA OAR) and Chet Koblinsky (NOAA/OAR Director for Climate), NOAA Geophysical Fluid Dynamics Laboratory, Princeton, NJ, 21 January 2005. Also in PowerPoint.
21. Wittenberg, A. T., and G. A. Vecchi, 2004: Reassessing the role of stochastic forcing in ENSO events.
    • Harvard University, Cambridge, MA, 16 November 2004.
    • Lamont-Doherty Earth Observatory, Palisades, NY, 3 December 2004.
22. Wittenberg, A. T., G. Vecchi, T. Rosati, M. Harrison, S. Zhang, I. Held, R. Gudgel, and the GFDL Model Development Teams, 2004: Simulation and prediction of El Niño at the Geophysical Fluid Dynamics Laboratory.   Oregon State University, Corvallis, OR, 11 November 2004.
23. Rosati, A., M. Harrison, A. Wittenberg, and S. Zhang, 2005: NOAA/GFDL ocean data assimilation activities.  CLIVAR Workshop on Ocean Reanalysis, NCAR, Boulder, CO, 9 November 2004.
24. Wittenberg, A. T., and A. Rosati, 2004: Tropical Pacific Climate & ENSO in the GFDL CM2/2.1 control simulations.  NOAA Geophysical Fluid Dynamics Laboratory, Princeton, NJ, 19 August 2004.  See also the CM2 handout and the CM2.1 handout.
25. Galanti, E., M. Tippet, S. Zebiak, S DeWitt, A. T. Wittenberg, M. Harrison, T. Rosati, and M. Rienecker, 2004: On data assimilation and ENSO dynamical prediction.   International Research Institute for Climate Prediction, Palisades, NY, 30 June 2004.
26. Wittenberg, A. T., and E. Galanti, 2004: Assessing the impact of stochastic forcing on ENSO events.  2004 Joint Assembly, Montreal, Canada, 19 May 2004.
27. W. Stern, A. Rosati, R. Gudgel, M. Harrison, and A. T. Wittenberg, 2004: Subseasonal to interannual prediction sensitivities in the GFDL/FMS GCM.  84th AMS Annual Meeting, Seattle, WA, 13 January 2004.
28. Wittenberg, A. T., T. Rosati, and I. Held, 2003: ENSO in the GFDL coupled model.  8th Annual CCSM Workshop, Breckenridge, CO, 24 June 2003.
29. Wittenberg, A. T., and M. J. Harrison, 2003: A baseline statistical model for tropical Pacific wind stress anomalies.  Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, 17 February 2003.
30. Wittenberg, A. T., 2002: ENSO response to altered climates. NOAA Geophysical Fluid Dynamics Laboratory, Princeton, NJ, 2 May 2002.
31. Wittenberg, A. T., 2002: Understanding the sensitivity of ENSO to the tropical climatology.  International Research Institute for Climate Prediction, Palisades, NY, 11 January 2002.
32. Wittenberg, A. T., 1996: Dynamics of tropical cyclones.  Workshop on Science for Tomorrow, Japan Association for Mathematical Sciences, Hokkaido, Japan, 27 July 1996.

Posters

1. Anderson, W., A. Gnanadesikan, and A. Wittenberg, 2008: The role of ocean color in the variability of the tropical Pacific.  NASA Carbon Cycle & Ecosystems Joint Science Workshop, Adelphi, MD, 28 April 2008.
2. Wittenberg, A. T., 2007: Addressing tropical biases in GFDL's global coupled climate models.
   • Third WGNE Workshop on Systematic Errors in Climate and NWP Models, San Francisco, CA, 14 February 2007.
   • 12th Annual CCSM Workshop, Breckenridge, CO, 19-21 June 2007.
3. Wittenberg, A. T., G. A. Vecchi, and A. Rosati, 2006: Simulated CO2-induced changes in tropical climate and variability.
   • 13th Ocean Sciences Meeting, Honolulu, HI, 22 February 2006
   • 11th Annual CCSM Workshop, Breckenridge, CO, 20-22 June 2006.
4. Capotondi, A., A. T. Wittenberg, and S. Masina, 2006: Temporal structure of ENSO in 20th century climate simulations.  13th Ocean Sciences Meeting, Honolulu, HI, 21 February 2006.
5. Wittenberg, A. T., A. Rosati, N.-C. Lau, and J. J. Ploshay, 2005: GFDL's CM2 global coupled climate models: Tropical Pacific climate and ENSO.  10th Annual CCSM Workshop, Breckenridge, CO, 21-23 June 2005.
6. Wittenberg, A. T., and A. Rosati, 2004: Tropical Pacific climate & variability in the GFDL CM2 global coupled GCM.
   • First International CLIVAR Science Conference, Baltimore, MD, 21-25 June 2004.
   • 9th Annual CCSM Workshop, Santa Fe, NM, 7-9 July 2004.
7. Wittenberg, A. T., and A. Rosati, 2004: Sensitivities of ENSO: Lessons from the GFDL CM2 global coupled GCM.
   • First International CLIVAR Science Conference, Baltimore, MD, 21-25 June 2004.
   • 9th Annual CCSM Workshop, Santa Fe, NM, 7-9 July 2004.
8. Wittenberg, A. T., and S. G. H. Philander, 2004: The Pacific cold tongue and ENSO: Sensitivity to the meridional wind stress climatology.  12th Ocean Sciences Meeting, Portland, OR, 30 January 2004.
9. Wittenberg, A. T., and M. J. Harrison, 2003: A baseline statistical model for tropical Pacific wind stress anomalies.  14th Conference on Atmospheric & Oceanic Fluid Dynamics, San Antonio, TX, 11 June 2003.
10. Wittenberg, A. T., 2002: What is the wind stress over the tropical Pacific?  AGU Fall Meeting, San Francisco, CA, 10 December 2002.
11. Wittenberg, A. T., 1999: Modulation of ENSO by changes in tropical climate.  Eighth Conference on Climate Variations, Denver, CO, 15 September 1999.

Professional Societies

Advising

• Kate Eckerle, Carnegie Mellon University (5/29/2007 - 8/1/2007)
  Project: Assessing the Indonesian Throughflow in GFDL's coupled GCMs

• Jarret Petrillo, Union County Magnet H.S., Scotch Plains, NJ (10/2006 - 3/2007)
  Project: Characterizing El Niño in observations and model simulations

Awards and Honors

Other Activities

Personal Interests: running, cycling, hiking, skiing, ballroom & latin dancing, juggling

Last updated: 24 August 2009