Extreme events Objective characterizing ecosystemcarbon response to extreme
Extreme events Objective: characterizing ecosystem/carbon response to extreme climate events; understanding the processes and mechanisms that will be useful for future projections Method: using a suite of models and data: foward/inversion/flux/satellite Forcings: PDSI, P, Temp, … n n Correlation analysis Sensitivity experiments Processes: NPP, Rh, … Which events: 2002 (also 2007? , 3+ models)
Comparison, validation, synthesis A Inversion Carbon data assimilation Carbon fluxes Observed Climate+ Precipitation, temp, radiation, etc. CO 2 Land use Forcing Mechanistic carbon models LAI, NPP Fire NEE GPP, Re NPP Site flux measurements Forest/agriculture inventory Satellite: NDVI EVI LAI Fire and derived C-fluxes
Inversion Forward
NEE anomalies with 2000 -05 mean removed 2002: drought 2004: ?
Inversion Forward
MODIS GPP MODIS LAI
Variability of the North American Carbon Cycle The big question is, how much would it really cost Ning Zeng and Jinho Yoon Dept. Atmospheric and Oceanic Science and Earth System Science Interdisciplinary Center University of Maryland Collaborators: G. J. Collatz, M. Heimman, C. Roedenbeck, H. Qian, R. Joseph, A. Kumar, A. Vintzileos, A. Mariotti, A. Busalacchi, S. Lord
The VEgetation-Global Atmosphere-Soil Model (VEGA Atmospheric CO 2 Photosynthesis Carbon allocation Turnover Autotrophic respiration 4 Plant Functional Types Broadleaf tree Needleleaf tree C 3 Grass (cold) C 4 Grass (warm) 3 Vegetation carbon poo Leaf Root Heterotrophic Wood respiration 3 Soil carbon pools: Fast Intermediate Slow
VEGAS II Photosynthesis: Light (PAR, LAI, Height), soil moisture, temperature, CO 2 Respiration: temperature, soil moisture, lower soil pools slower decay Competition: Net growth, shading => fractional cover Fire: moisture, fuel load, PFT dependent resistance Wetland/CH 4:
Conclusions § There is large differences in the spatial and temporal variability on continental-regional scale among the models § There is some agreement, especially associated with major climatic events such as drought among forward, inversion and satellite data
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