IGPP Seminar Series

Isotopic Fingerprints Reveal Terrestrial Carbon and Water Exchange Across Scales

by Ulrike Seibt, Sponsored by the Geoscience Initiative
Stanford University

Abstract

We have a good mechanistic understanding of gas exchange at the leaf scale, and extensive data on carbon cycling at the global scale. But there is a gap in quantifying terrestrial processes on the intermediate scales. I will present studies combining theoretical analyses, measurements and coupled models using isotope tracers that give unique insights on terrestrial carbon and water cycles, and provide links between local, regional and global scales. For example, non-steady state effects in the cycling of water at the plant scale affect the oxygen isotope signature that is imprinted on atmospheric CO2. Thus, these effects are also relevant for inversion studies and models that use atmospheric CO2 and isotope data at the global scale. At the regional scale, soil moisture-precipitation feedbacks are an important mechanism that may amplify seasonal climate anomalies, contributing to extreme events such as the 2002 "flood of the Century" in Europe.
Tuesday, 27 May 2008
3853 Slichter Hall
Refreshments at 3:45 PM
Lecture at 4:00 PM