GEOS-CHEM meeting:GEOS-CHEM meeting:Effects of enhanced boreal forest fires on global Effects of enhanced boreal forest fires on global

COCO

Fok-Yan Leung Fok-Yan Leung

with help and thanks to with help and thanks to

Jennifer Logan, Ed Hyer, Eric Kasischke, David Jennifer Logan, Ed Hyer, Eric Kasischke, David Streets, Leonid Yurganov and Rose Yevich.Streets, Leonid Yurganov and Rose Yevich.

Harvard UniversityHarvard University

5 April 2005.5 April 2005.

Model version used in studiesModel version used in studies

v5.05.03 for 1998 GEOS3 meteorology v5.05.03 for 1998 GEOS3 meteorology

v7.02.02 for 2002 GEOS4 meteorologyv7.02.02 for 2002 GEOS4 meteorology

Difference in mean global OH between the Difference in mean global OH between the versions for 2001 simulation is ~10.55 x 10versions for 2001 simulation is ~10.55 x 1055 molecules/cmmolecules/cm33 in v7.02.02 vs. ~10.15 x 10 in v7.02.02 vs. ~10.15 x 1055 molecules/cmmolecules/cm33 in v5.05.03 in v5.05.03

Default GEOS-CHEM setting is to have all Default GEOS-CHEM setting is to have all BIOBSRCE emissions distributed in the BIOBSRCE emissions distributed in the boundary layerboundary layer

Important Issues involving boreal Important Issues involving boreal forest burningforest burning

Consideration of ground fuel burning and Consideration of ground fuel burning and fire regimes to emissions estimatesfire regimes to emissions estimates

Sensitivity of model results to injection Sensitivity of model results to injection heights of boreal forest biomass burning heights of boreal forest biomass burning emissions.emissions.

Flaws in either emissions estimates or Flaws in either emissions estimates or parameterization of model or both – case parameterization of model or both – case studies of 1998 vs 2002.studies of 1998 vs 2002.

1998 emissions , Russia1998 emissions , Russia

Comparison of GEOS-CHEM results with CMDL Comparison of GEOS-CHEM results with CMDL surface site data- 1998 resultssurface site data- 1998 results

Comparison of GEOS-CHEM results with ground Comparison of GEOS-CHEM results with ground based column data – 1998 Resultsbased column data – 1998 Results

Comparison of GEOS-CHEM results with CMDL Comparison of GEOS-CHEM results with CMDL surface site data; the effect of injection heightssurface site data; the effect of injection heights

Comparison of GEOS-CHEM results with ground Comparison of GEOS-CHEM results with ground based column data; the effect of injection heightsbased column data; the effect of injection heights

Comparison of drymassburned between 1998 and 2002 (KAS98 and KAS02)Comparison of drymassburned between 1998 and 2002 (KAS98 and KAS02)

Comparison between 1998 and 2002; model and Comparison between 1998 and 2002; model and CMDL surface dataCMDL surface data

Comparison between 1998 and 2002; column dataComparison between 1998 and 2002; column data

Differences between emission sets Differences between emission sets that make a differencethat make a difference

Treatment of vegetation types (i.e. vegetation maps) Treatment of vegetation types (i.e. vegetation maps) – Forest vs. peatland burning (implications for injection heights)Forest vs. peatland burning (implications for injection heights)

Assumptions about carbon loading, both above ground Assumptions about carbon loading, both above ground and below ground fuelsand below ground fuels– Also, what is the latitudinal dependence of fuel loading?Also, what is the latitudinal dependence of fuel loading?

Assumptions about fire regimes – seasonal variationsAssumptions about fire regimes – seasonal variations– crown fires vs surface fires, and the fraction of fuel burnedcrown fires vs surface fires, and the fraction of fuel burned– Depth of below ground fuels burnedDepth of below ground fuels burned– What is the relationship between burning and hotspots?What is the relationship between burning and hotspots?

Emission factors – a function of both fire regime and Emission factors – a function of both fire regime and vegetation typevegetation typeAreas burned and how important are the geographical Areas burned and how important are the geographical locations of the Siberian fires?locations of the Siberian fires?

Are the problems actually in the Are the problems actually in the emissions set?emissions set?

Or are there issues in the model that Or are there issues in the model that alsoalso need to be considered?need to be considered?

Appendices Appendices

1998 and 2002 – high fire years (from Kasischke 1998 and 2002 – high fire years (from Kasischke et al., 2004)et al., 2004)

Assumptions about fires KAS98 and KAS02 Assumptions about fires KAS98 and KAS02 (Kasischke et al., 2004)(Kasischke et al., 2004)

Comparison of GEOS-CHEM results with CMDL Comparison of GEOS-CHEM results with CMDL surface site data; anomaly 1998 resultssurface site data; anomaly 1998 results

Comparison of GEOS-CHEM results with ground Comparison of GEOS-CHEM results with ground based column data; anomaly - 1998 resultsbased column data; anomaly - 1998 results

Comparison of GEOS-CHEM results with CMDL Comparison of GEOS-CHEM results with CMDL surface site data; the effect of injection heightssurface site data; the effect of injection heights

AnomalyAnomaly

Comparison of GEOS-CHEM results with ground Comparison of GEOS-CHEM results with ground based column data; the effect of injection heightsbased column data; the effect of injection heights

AnomalyAnomaly