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


June 1st: Dr. Navjit Sagoo, Postdoctoral Associate, Yale University. Host: Frankie Pavia.

"Dust, ice-clouds and climate: how do the ice-nucleating properties of dust affect past climates with different atmospheric dust loads?"

Abstract:

Aerosols and clouds represent the largest source of uncertainty in constraining radiative forcing during the industrial era and thus aerosol-cloud-climate interactions are a key area of research. Aerosols in the past, before pollution, were very different to today as the atmosphere was much cleaner. Quantifying and understanding aerosol-cloud interactions in the past is important in order to understand and quantify the effect of the background component of aerosols.

Mineral dust is an ubiquitous atmospheric aerosol and dustiness has varied greatly in the past. Dust affects climate in several ways, it absorbs and scatters radiation in the atmosphere and modifies biogeochemical cycles. However, dust is the most important ice nuclei (IN) in the atmosphere. The presence of dust in the atmosphere allows ice-crystals to form at warmer temperatures and at lower relative humidity than in the absence of dust. Subsequently variations in atmospheric dust load can have a significant effect on cloud physical and radiative properties, and therefore climate.

We use a global coupled climate model with an interactive dust cycle (DEAD) and allow dust to act as IN in the climate model. Global dustiness is modified to represent a high dust case – an idealized analogy to the Last Glacial Maximum (LGM) and a low dust case analogous to the Pliocene Warm period. We also run low and high CO2 cases to represent the former and latter. Including dust as an IN has a powerful impact on cloud radiative forcing and the climate.


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.