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Extreme events

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, …

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Extreme events

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  1. 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, … • Correlation analysis • Sensitivity experiments • Processes: NPP, Rh, … • Which events: 2002 (also 2007?, 3+ models)

  2. Inversion Carbon data assimilation Site flux measurements Forest/agriculture inventory Comparison, validation, synthesis A Carbon fluxes Observed Climate+ Satellite: NDVI EVI LAI Fire and derived C-fluxes Precipitation, temp, radiation, etc. CO2 Land use Forcing Mechanistic carbon models LAI, NPP Fire NEE GPP, Re NPP

  3. Inversion Forward

  4. NEE anomalies with 2000-05 mean removed 2002: drought 2004: ?

  5. Inversion Forward

  6. MODIS GPP MODIS LAI

  7. Variability of the North American Carbon Cycle • Ning Zeng and Jinho Yoon • Dept. Atmospheric and Oceanic Science and • Earth System Science Interdisciplinary Center • University of Maryland The big question is, how much would it really cost Collaborators: G. J. Collatz, M. Heimman, C. Roedenbeck, H. Qian, R. Joseph, A. Kumar, A. Vintzileos, A. Mariotti, A. Busalacchi, S. Lord

  8. Atmospheric CO2 Photosynthesis Autotrophic respiration The VEgetation-Global Atmosphere-Soil Model (VEGAS) 4 Plant Functional Types: Broadleaf tree Needleleaf tree C3 Grass (cold) C4 Grass (warm) 3 Vegetation carbon pools: Leaf Root Wood Carbon allocation Heterotrophic respiration Turnover 3 Soil carbon pools: Fast Intermediate Slow

  9. VEGAS II Photosynthesis: Light (PAR, LAI, Height), soil moisture, temperature, CO2 Respiration: temperature, soil moisture, lower soil pools slower decay Competition: Net growth, shading => fractional cover Fire: moisture, fuel load, PFT dependent resistance Wetland/CH4: moisture, topography gradient Carbon 13: C3/C4 competition: temperature, CO2

  10. 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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