Evaluation of Fire Parameterizations in CLM-CN and

Its Climatic Impact

Ying Sun and Robert E. Dickinson

Department of Geological Sciences Jackson School of Geosciences

The University of Texas at Austin

Feb 10th, 2010

LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin)

Motivation

Approaches

Experiment Design

Results

Summary

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Outline

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LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin)

Motivation

Approaches

Experiment Design

Results

Summary

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Outline

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LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin)

Motivation

Terrestrial Ecosystem

Coupled Climate-Carbon Cycle Models

Global Change Prediction

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Atmospheric Chemistry Climate

Land Surface Energy Balance

Carbon & Nutrient

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Trace Gases

Aerosols

Albedo

Ecosys Struc

LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin)

Motivation

Approaches

Experiment Design

Results

Summary

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Outline

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LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin) 6/21

])(exp[)( 2

emmmP ⋅−= π

)()( sfssA ⋅=

)exp()( 23 dscsbsassf

+′⋅+′⋅+′⋅′

=

Fire Occurrence Probability

Area Burned

Minfuel = 100 gC/m2

Approach

Statistical Scheme(Thonicke et al, 2001)

LPJ-DGVM

Pros: 1 varCons: 4 parameters

A.

LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin) 7/21

Fire Occurrence Probability

Area Burned

Extinguishing Fire

Approach

Process-based Scheme

(Arora & Boer, 2005)

CTEM

Pros: DetailsCons: General ???

Sensitivity

B.

LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin) 8/21

ApproachB.

Correlation Coefficient: Ws ~ A

(Arora & Boer, 2005)

LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin) 9/21

Flammability Estimation

Ignition Sources

Fire Suppression

Ubiquitous Model

Approach

Global Parameterization

(Pechony & Shindell, 2009)

P: GPCPv2T: NCAR/NCEPLAI: MODISPD: GPWv3

C.

Pros: Simple + GlobalCons: P ???

LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin)

Motivation

Approaches

Experiment Design

Results

Summary

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Outline

10/21

LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin) 11/21

Assume: Ubiquitous

Experiment Deign

cR, w

)( pem

m* w

CLM-CN

Statistical Scheme: ms = m/me

Global Par:Flammability F

GFEDv2: A

NCEP: T

CLM: RH, ms

LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin)

Run Fire Module Time period

1. CNT ON 1948-2004

2. DEF OFF 1948-20043. MOD1 MODIS (scaled) 1948-20044. MOD2 MODIS 1948-2004

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Experiment Design

Run Fire Module Time period

CN-CTL Default (Thonicke et al, 2001) 1997-2004CN-MOD Reparameterization 1997-2004

Expt1: Comparison of 2 Fire modules

Expt2: Sensitivity of Terrestrial and

Climatic Changes to Estimated Fires

LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin)

Motivation

Approaches

Experiment Design

Results

Summary

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Outline

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LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin)

Annual Fractional Burned Area (%)

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Results

LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin) 15/21

Results

LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin)

Factor = MOD2:MOD1 = 1440

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Results

LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin)

1. LAI – Leaf Area Index

2. NPP – Net Primary Production

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Results

LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin)

(Zhao, 2007)

3. ET –Evaptranspiration

18/21

Results

LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin)

Motivation

Approaches

Experiment Design

Results

Summary

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Outline

19/21

LMWG/BGCWGFire DynamicsY. Sun (DGS, UT at Austin) 20/21

Future Work

Transient Simulation

Deforest Fires

Anthropogenic Influence

Ignition Distribution

Fire Activity ~ ENSO

Acknowledgements

Dr. Muhammad Shaikh

21/21

Thank you for attention!

Questions and Comments?

Dr. Kaicun Wang