.	Home Research Vita Publications Teaching Links Grad Students Home Geosciences Home		Peter J. DiFiore Graduate Student Department of Geosciences  321a Guyot Hall Princeton University Princeton , NJ 08544 Phone: (609) 258-7544 E-Mail: pdifiore@princeton.edu Advisor: Daniel M. Sigman
	Research interest: My interests are broadly in the application of stable isotopes of biologically relevant elements (in particular, the N and O isotopes of nitrate) to understand the interactions among biogeochemistry, ocean circulation, and climate change. Recent work has focused on the application of nitrate N and O stable isotopes to: 1) constrain biological uptake and nutrient sources in the Subantarctic Zone of the Southern Ocean. 2) quantify gross inputs of denitrification and nitrogen fication in the eastern tropical North Pacific. 3) place quantitative limits on the level of nitrification in the Polar Antarctic mixed layer. 4) estimate Nitrogen fixation rates in the Atlantic basin. Committee members: Daniel Sigman, Michael Bender, Jorge Sarmiento News and upcoming events: ***Check out our GEO 499 publication in the October 2007 issue of Geotimes Magazine here and a news story about it here and picked up by the San Diego Union-Tribune here*** "Antarctic Zone Biogeochemistry - Insights from the Stable Isotopes of Nitrate" at Fall 2007 AGU meeting in San Francisco, CA. Section B05 - Biogeochemistry in Polar Environments. Check out the Association of Polar Early Career Scientists (APECS) website here