1 / 18

Volcanic and Solar Forcing of El Nino over the Past 1000 Years

Volcanic and Solar Forcing of El Nino over the Past 1000 Years. Michael E. Mann. Department of Environmental Sciences, University of Virginia, Charlottesville, VA. Mark A. Cane. Lamont Doherty Earth Observatory, Columbia University, New York, NY. Stephen E. Zebiak.

shay
Download Presentation

Volcanic and Solar Forcing of El Nino over the Past 1000 Years

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Volcanic and Solar Forcing of El Nino over the Past 1000 Years Michael E. Mann Department of Environmental Sciences, University of Virginia, Charlottesville, VA Mark A. Cane Lamont Doherty Earth Observatory, Columbia University, New York, NY Stephen E. Zebiak International Research Institute For Climate Prediction, Palisades, NY Amy Clement Rosensteil School of Oceanography, University of Miami, Miami, FL European Geophysical UnionNice, France April 27, 2004

  2. 1000 1200 1400 1600 1800 2000 Influence of Natural Radiative Forcing Crowley, T.J., Causes of Climate Change Over the Past 1000 Years, Science, 289 270-277, 2000. Volcanism Solar

  3. Jones, P.D., Mann, M.E., Climate Over Past Millennia, Reviews of Geophysics, in press, 2004.

  4. Volcanic Forcing of El Nino? Adams, J.B., Mann, M.E., Ammann, C.M., Proxy evidence for an El Nino-like Response to Volcanic Forcing, Nature, 426, 274-278, 2003.

  5. Volcanic Forcing of El Nino? Adams, J.B., Mann, M.E., Ammann, C.M., Proxy evidence for an El Nino-like Response to Volcanic Forcing, Nature, 426, 274-278, 2003.

  6. Solar Forcing of El Nino? Decadally-smoothed Mann et al NINO3 (x-1) Jones et al, Science, 2001 Verschuren et al, Nature, 403, 410-414, 2000.

  7. Theoretical mechanism for natural radiative forcing of El Nino Cane, M.A., A.C. Clement, A. Kaplan, Y. Kushnir, D. Pozdnyakov, R. Seager, S.E. Zebiak, and R. Murtugudde, Twentieth-Century Sea Surface Temperature Trends, Science, 275, 957-960, 1997.

  8. Theoretical mechanism for natural radiative forcing of El Nino Composite Nino3 (100 realizations of CZ model) Tropical Volcanic radiative forcing (0.1 x W/m2)

  9. Theoretical mechanism for natural radiative forcing of El Nino Mann, M.E., Cane, M.A., Zebiak, S.E., Clement, A., Volcanic and Solar Forcing of El Niño Over the Past 1000 Years, submitted, 2004. Response to Volcanic Forcing Composite Nino3 (100 realizations of CZ model) Tropical Volcanic radiative forcing (0.1 x W/m2)

  10. Superposed Epoch Analysis AD 1649-1868 Superposed Epoch Analysis AD 1000-1999 all (7) tropical events exceeding -2 W/m2 All (7) tropical events exceeding -4 W/m2 Theoretical mechanism for natural radiative forcing of El Nino Mann, M.E., Cane, M.A., Zebiak, S.E., Clement, A., Volcanic and Solar Forcing of El Niño Over the Past 1000 Years, submitted, 2004. Tropical volcanic radiative forcing (0.1 x W/m2)

  11. Theoretical mechanism for natural radiative forcing of El Nino Composite Nino3 (100 realizations of CZ model) Tropical Solar radiative forcing (W/m2) Tropical volcanic radiative forcing (0.1 x W/m2) 40 year smooth

  12. Theoretical mechanism for natural radiative forcing of El Nino Response to Solar Forcing Composite Nino3 (100 realizations of CZ model) 40 year smooth Tropical Solar radiative forcing (W/m2) 40 year smooth Mann, M.E., Cane, M.A., Zebiak, S.E., Clement, A., Volcanic and Solar Forcing of El Niño Over the Past 1000 Years, submitted, 2004.

  13. Theoretical mechanism for natural radiative forcing of El Nino Cobb, K.M., C.D. Charles, R.L Edwards, H. Cheng, El Niño-Southern Oscillation and tropical Pacific climate during the last millennium, Nature, 424, 271-276, 2003.

  14. Theoretical mechanism for natural radiative forcing of El Nino Combined response to Solar +Volcanic Forcing Palymra coral isotopes (standardized to have same mean and standard deviation as Nino3 composite series) Ensemble mean Nino3 (100 realizations of CZ model) 40 year smooth Mann, M.E., Cane, M.A., Zebiak, S.E., Clement, A., Volcanic and Solar Forcing of El Niño Over the Past 1000 Years, submitted, 2004.

  15. Mann, M.E., Ammann, C., Bradley, R.S., Briffa, K., Crowley, T.J., Hughes, M.K., Jones, P.D., Oppenheimer, M., Osborn, T.J., Overpeck, J.T., Rutherford, S., Trenberth, K.E., Wigley, T.M.L., On Past Temperatures and Anomalous late 20th Century Warmth, Eos, 84, 256-258, 2003 [MODIFIED: Boreholes—Rutherford and Mann (in press); Crowley & Lowery (updated)]

  16. Greater variability in extratropics and summer! Mann, M.E., Ammann, C., Bradley, R.S., Briffa, K., Crowley, T.J., Hughes, M.K., Jones, P.D., Oppenheimer, M., Osborn, T.J., Overpeck, J.T., Rutherford, S., Trenberth, K.E., Wigley, T.M.L., On Past Temperatures and Anomalous late 20th Century Warmth, Eos, 84, 256-258, 2003 [MODIFIED: Boreholes—Rutherford and Mann (in press); Crowley & Lowery (updated)]

  17. CONCLUSIONS • Observations of an El Nino-like response to explosive tropical volcanic eruptions are consistent with results based on simulations with the Cane-Zebiak model • Coral evidence of La Nina-like anomalies during the 12th-early 13th centuries, and El Nino-like anomalies during the late 17th century, are reproduced by the simulated response to total (solar+volcanic) natural radiative forcing • Differences between empirical estimates of extratropical and full (combined tropical and extratropical) hemispheric mean temperature changes in past centuries may reflect the importance of tropical dynamical responses.

  18. Jones, P.D., Mann, M.E., Climate Over Past Millennia, Reviews of Geophysics, in press, 2004.

More Related