Title：Simulating δ18O and 14C in CESM ocean model and its application to understanding paleocean evolution
Speaker：Dr. ZHANG Jiaxu
Time: 15:30pm, 2014.05.23
Venue：Room 412, Laoshan Campus
About the speaker： University of Wisconsin-Madison, USA
Abstract:
Earth System Models (ESMs) have been used to understand paleoclimate evolution as an independent line of evidence beside past proxy records. However, one great challenge for model-data comparison is that ESMs usually do not directly simulate geochemical variables that can be compared directly with proxies. We meet this challenge by developing the simulation capability of a series of major geotracers, including water isotopes, in a state-of-art ESM, the Community Earth System Model (CESM). Here I focus on the water isotope (δ18O) and radiocarbon (14C) simulation in the ocean component of CESM. A surface isotopic flux forcing is introduced into the ocean model to represent the fractionation process and concentration change. The model performance in simulating δ18O and 14C is evaluated based on the comparison with observations. I also show the simulated δ18O and 14C during the Last Glacial Maximum, and its potential application on understanding the ocean evolution during the last deglaciation.
