HR: 16:50h
AN: B52E-04    [PDF]
TI: Carbon Cycle and Vegetation Dynamics in the GFDL-Princeton University Coupled Atmosphere-Biosphere Model
AU: * Shevliakova, E
EM: elena@eno.princeton.edu
AF: Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544 United States
AU: Pacala, S W
EM: pacala@princeton.edu
AF: Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544 United States
AU: Malyshev, S
EM: malyshev@princeton.edu
AF: Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544 United States
AU: Hurtt, G C
EM: george.hurtt@unh.edu
AF: Institute for the Study of Earth, Oceans and Space, University of New Hampshire, Durham, NH 03824 United States
AU: Caspersen, J P
EM: john.caspersen@utoronto.ca
AF: Faculty of Forestry,University of Toronto, 33 Willcocks S, Toronto, ONT M5S 3B3 Canada
AB: Modeling global interactions between the atmosphere, hydrosphere and biosphere continues to pose a significant challenge, because of the tight and complex coupling of flows of water, energy, greenhouse gases, and ecosystem dynamics. We developed a comprehensive dynamic land surface model (LM3) able to simulate carbon and vegetation dynamics on time scales from minutes to centuries, as well as the exchange of water and energy among the land, LM3 predicts carbon dynamics in vegetation and soil in response to environmental conditions (weather, climate and soil type), ambient concentration of CO2, natural disturbances (e.g. fire), and anthropogenic land use changes (e.g. deforestation, agricultural cropland abandonment and forest management). A suite of the historical 300 years land cover change scenarios (developed at University of New Hampshire) is used to represent direct anthropogenic forcing on the terrestrial carbon system. Here we analyze the behavior of LM3 forced with observed atmospheric data and coupled with GFDL atmospheric circulation model AM2. The series of experiments indicates that our model adequately simulates climatic gradients of net primary productivity (NPP), leaf area index (LAI), biomass accumulation, evapotranspiration, and runoff. Additionally, analysis of the simulations suggests that anthropogenic land use has been a major forcing on the terrestrial carbon cycle, with large sources of CO2 caused primarily by deforestation and timber harvesting in the current tropics and past north temperate zone, and large current north temperate sinks caused primarily by secondary forest growth.
DE: 0400 Biogeosciences
SC: Biogeosciences [B]
MN: 2003 Fall Meeting