Biology & Paleo Environment Events

For upcoming seminars, see our calendar here.

Current Seminar Managers: Cassaundra Rose and Samuel Phelps 

Time and Location: Mondays at 12 pm, Comer Seminar Room


May 18th: Dr. Brad Linsley, Lamont Research Professor, LDEO.

"Coral Records of PDO and ENSO Variability in the South Pacific: New Results from the Expanding Coral Network."

Abstract:

Part 1: Decadal-scale anomalies in surface temperatures, trade winds, sea level pressure and rainfall in the Pacific basin that have developed since the start of the recent hiatus in Earth surface warming (~1999 C.E.) resemble the negative phase of the Pacific Decadal Oscillation (PDO). We have recently generated an annual average composite coral Sr/Ca-derived sea surface temperature (SST) time-series extending back to 1791 derived using 3 coral cores from Fiji, Tonga and Rarotonga (FTR) in the PDO sensitive region of the SW Pacific (Linsley et al., 2015; April 8th, Geophys. Res. Lett.). Decades of warmer (cooler) FTR SST co-occur with PDO negative (positive) phases and positively correlate with South Pacific oceanic heat content (OHC)(0-700m). Decadal changes in FTR coral Sr/Ca SST appear to be a proxy for both the PDO and South Pacific 0-700m ocean heat content. FTR SST is also inversely correlated with decadal changes in equatorial SST as measured by equatorial coral Sr/Ca records. Collectively, these results support the fluctuating trade wind-shallow meridional overturning cell mechanism for decadal modulation of Pacific SSTs and ocean heat content. They also add to the growing body of information indicating the climatic importance of the PDO.
Part 2: An open and debated question is the relationship between the PDO and ENSO. We are currently analyzing a 460 year long coral core from Ta’u (in American Samoa 800-1200km NE of Tonga-Fiji) on the present nodal point (zero correlation line) for both the PDO and ENSO. We hypothesize that decadal and interannual variability in coral oxygen isotopes at this site can tell us something about the relationship between the PDO and ENSO in this region. Our preliminary results indicate that the nodal lines for both the PDO and ENSO have shifted significantly and independently of each other in the past. I will discuss our preliminary interpretations of this new data from American Samoa.

 


Spring 2015:

  • February 2nd: Postponed due to winter storm
  • February 9th: Dr. Todd Sowers, Senior Scientist EESI, Penn State. Host: Pratigya Polissar. "Methane Isotope Records Spanning the last 160kyr: Correlations and Conundrums."
  • SPECIAL SEMINAR February 13th @ 1 pm: Dr. Matt Bekker, Brigham Young University. Host: Brendan Buckley. "Lessons from Centennial- and Millennial-length Reconstructions of Northern Utah’s Hydroclimate from Tree Rings."
  • February 16th: open
  • February 23rd: Dr. Lidya Tarhan, Postdoctoral Researcher, Yale University. Host: Cassaundra Rose. "Protracted Development of Bioturbation through the Early Paleozoic."
  • March 2nd, 2 pm: Dr. Christa Farmer, Hofstra. Host: Mike Kaplan. “Learning from the Impacts of Superstorm Sandy: Paleotempestology on Long Island.”
  • March 9th: Dr. Carling Hay, Postdoctoral Fellow, Harvard University. Host: Maureen Raymo. "Revisiting the Past: Fingerprinting the Sources of 20th Century Global Sea-Level Rise."
  • March 16th: open/Spring Break
  • March 23rd: Dr. Ailene Ettinger, Putnam Fellow, The Arnold Arboretum of Harvard University. Host: Ben Cook. "Testing the limits: effects of climate & competition on tree ranges in a warming world"
  • March 30th: Dr. Steven Smriga, MIT. Host: Andrew Juhl. "Dissecting the Phycosphere: Upscaling Bacterial Consumption Near Individual Diatoms."
  • April 6th: Dr. Jodi Young, Postdoctoral Researcher, Princeton University. Host: Kim Popendorf. "Physiological mechanisms supporting high net primary productivity in the Western Antarctic Peninsula."
  • SPECIAL SEMINAR April 6th, 2:30 p.m.: Dr. Erik Cordes, Associate Professor, Temple University. Host: Andy Juhl. "Understanding the Deep Sea in the Anthropocene: Oil spills and ocean acidification threaten deep-water corals in the Gulf of Mexico."
  • April 13th, 2 pm: Dr. Mrinalini Nikrad, Postdoc, Rutgers. Host: Jeff Bowman. "Microbial response to changing climate in sub-zero ocean and soil ecosystems."
  • April 20th: Dr. Aldo Shemesh, Weizmann Institute. Host: Yoni Goldsmith. "Recent unprecedented state of eastern Mediterranean Sea within the last millennium."
  • April 27th: Dr. Jennifer Stanford, Drexel University. Host: Andy Juhl. "Changing How We Teach: Evidence-Based Approaches to Promote STEM Student Retention."
  • SPECIAL SEMINAR May 1st @ 9 am & 1:00 pm: Dr. Steven Meyers. Host: Maureen Raymo.
    • 9 am: Decoding climate rhythms with “Astrochon: An R Package for Astrochronology”
    • 1 pm: "Climate “Noise” and the Cryosphere: New Constraints on the Evolution of Ice Sheets During the Cenozoic."
  • May 4th: Dr. Suni Shah Walter, Harvard University. Host: Kim Popendorf. "Lessons about microbe-mediated transformations of deep marine DOM from radiocarbon at the North Pond CORK site."
  • May 11th: Dr. Jack Scheff, Postdoc, LDEO, "Does greenhouse warming dry out the continents? Lessons from theory, proxies, and models"
  • May 18th: Dr. Brad Linsley, LDEO. American Samoa coral record of S. Pacific climate
  • June 1st: Dr. Navjit Sagoo, Postdoctoral Associate, Yale University. Host: Frankie Pavia. Tentative topic: dust and cloud physics in the Pliocene

Additional talks can be seen on the

google calendar.