Modeling Biogeochemical Cycles in the Central Great Plains
Nate Brunsell
Dept. of Geography, KU
with
Sharon Billings, Jesse Nippert, Jay Ham, John Blair and Kevin Price
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APRIL 19, 2008
Introduction
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Our task:
“To assess how climatic variability and climate change
interact with land use/land cover patterns to influence
ecosystem functioning, with an emphasis on
biogeochemical cycling in Central Plains grasslands.”
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Our approach:
To adopt a multi-scale approach in measurement
collection and modeling to quantify mechanistic
processes from leaf to region.
EPSCOR ECOFORECASTING ANNUAL MEETING
APRIL 19, 2008
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APRIL 19, 2008
Energy
Scale
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Diagnostic:
Determine the (co)­spectral relationships Energy
Modeling Approach
Scale
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Diagnostic:
Determine the (co)­spectral relationships
Energy
Modeling Approach
Prognostic:
Predict scale­wise responses to unknown (but with some associated probability function) forcing events at multiple/different spatial and temporal scales
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Scale
APRIL 19, 2008
Modeling Approach
large eddy simulation
SVAT scheme/water balance
regional climate/
meteorological models
ecosystem process model
stochastic analysis
global climate models
Energy
Approach:
Examine model outputs at native resolutions (validation etc.)
Use model output as forcing to higher resolution models (scenarios)
Scale
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APRIL 19, 2008
Global Climate Models
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APRIL 19, 2008
Verification of Global Climate Models
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Compared to GHCN data, GCM output is quite good
Can use Stochastic Weather Generators to downscale GCM PPT and air temperature to use as forcing in other models EPSCOR ECOFORECASTING ANNUAL MEETING
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Ecosystem Process Models
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Biome­BGC
Will be validated using Konza and NESA data
Use downscaled GCM for scenarios
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Rainfall Manipulation Studies
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Scenario assessment with Biome­BGC
Compared with RAMPS and Irrigation Studies at Konza
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APRIL 19, 2008
Regional Climate Models: Soil Moisture­Precipitation Feedbacks
Soil Moisture
2 km
4 km
8 km
Precipitation
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APRIL 19, 2008