Allan Spessa1,2, Kirsten Thonicke3,Colin Prentice3

Simulating Climate-Vegetation-Fire Interactions & Emissions: Regional

Applications of the LPJ-SPITFIRE Model

1. Max Planck Institute for Biogeochemistry, Jena, Germany 2. Hadley Centre (from 2006)3. Marie Curie Fellow, Bristol University4. QUEST & Bristol University

Key Research Questions for LPJ-SPITFIRE

1. Assess long-term changes in vegetation composition and above-ground carbon due to altered fire regimes, at regional and global scales.

2. Quantify emissions of different trace gases from biomass burning (CO2 etc), at regional and global scales.

3. Examine effects of regional climate phenomona (e.g. El Nino) on fire activity, vegetation, and emissions.

4. Investigate changes in human-caused ignition patterns.

Fire in the Earth Systempopulation

density

FIRE MODEL SIMULATES:Number of Fires, Area Burnt, Fire Intensity, Crown Scorch, Plant Mortality, andEmissions of CO2, CO, CH4, VOC, NOx & TPM. Temporal scale = 1 day.Spatial scale = 0.5 deg (flexible).

wind speed

Regional fire model (SPITFIRE)

lightning strike rate

LPJ-DGVMrainfall, cloud, temp.,

radiation

texture

[CO2]TrBlEgTrBlRgTeNlEgTeBlEgTeBlSgBoNlEgBoNlSgBoBlSgC3 grassC4 grass(Bare Soil)

1) Human and lightning-caused ignition rates. Gridcell variable (calibration data limited).

2) Surface rate of spread based on Rothermel family of models. ROS is directly proportional to energy produced by ignited fuel, and also wind. ROS is inversely proportional to the amount of energy required to ignite fuels.

3) Litter moisture = f (fire danger index);

4) Grass phenology (‘green-up’ and curing);

5) Raingreen tree phenology*;

6) Fire intensity (independent of rate of spread);

7) Fuel combustion (by fine and coarse fuel classes);

8) Tree mortality & crown fires = f (scorch height, cambial kill; vegetation-specific attributes);

9) Land cover change* adjust fire activity and emissions to natural vegetation regions, and

10) Emission factors (CO2, CO, CH4, VOC, TPM, NOx)

Emissions (tonnes/km2) × trace species × PFT × period (day, month or year).

* Not yet implemented

Key features of LPJ-SPITFIRE

• Beta version undergoing validation.• Long-term validation data on fire activity collated from several regions, covering most biomes (Iberian Peninsula, North Germany, Russia and Central Asia, Africa, Australia, Western USA, Canada, Borneo, Amazonia). • Data from various sources: satellite and ground observations, processed to a common format for model checking.• First simulation results:

Global, 1960-2000; Australian Wet-Dry Tropics, 1997-2002; and Central Asia and Siberia, 1996-2002.

Progress to date on LPJ-SPITFIRE

Northern Australia: Structural Vegetation Cover (GLC 2000)

Northern Australia:Observed Mean Annual Area Burnt, 1997-2002

(AVHRR FAA data, DOLA)

Northern Australia:Simulated Mean Annual Area Burnt, 1997-2002

(LPJ-SPITFIRE)

CentralTransect

EastTransect

Northern Australia: Simulated Monthly Area Burnt, 1997-2002 (LPJ-SPITFIRE)

Central Transect (North)

0

200

400

600

800

1000

1200

mea

n ar

ea b

urnt

per

gr

idce

ll [k

m²]

monthly simulated area burnt

monthly observed area burnt

Central Transect (middle)

0

50

100

150

200

250

300

350

400

mea

n ar

ea b

urnt

per

grid

cell

[km

²]

monthly simulated area burnt

monthly observed area burnt

Central Transect (South)

050

100150200250300350400450

mea

n ar

ea b

urnt

per

grid

cell

[km

²]

monthly simulated area burnt

monthly observed area burnt

East Transect (North)

0

100

200

300

400

500

600

700

mea

n ar

ea b

urnt

per

grid

cell

[km

²]

monthly simulated area burnt

monthly observed area burnt

East Transect (middle)

0

500

1000

1500

2000

2500

3000

3500

4000

mea

n ar

ea b

urnt

per

grid

cell

[km

²]

monthly simulated area burn

monthly observed area burnt

East Transect (South)

0

50

100

150

200

250

300

350

400

mea

n ar

ea b

urnt

per

grid

cell

[km

²]

monthly simulated area burnt

monthly observed area burnt

Northern Australia:Simulated C4 grass FPC, 2002

(LPJ-SPITFIRE)

Northern Australia:Simulated Tropical Broadleaved Raingreen FPC, 2002

(LPJ-SPITFIRE)

Northern Australia:Simulated Tropical Broadleaved Evergreen FPC, 2002

(LPJ-SPITFIRE)

Northern Australia:Simulated Mean Annual CO2 Emissions

(tonnes per sqkm), 1960-2002 (LPJ-SPITFIRE)

xxxxxxxSiberia & Central Asia:Observed Mean Annual Area Burnt, 1996-2002

(AVHRR data, Suhkinin et al., 2004)

xxxxxxxSiberia & Central Asia:

Simulated Mean Annual Area Burnt, 1997-2002 (LPJ-SPITFIRE)

xxxxxxxSiberia & Central Asia:

Simulated Mean Annual CO2 Emissions (tonnes per sq km), 1960-2002 (LPJ-SPITFIRE)

Next Steps and Future Directions Complete validation of simulated fire activity against

observed fire data from available regional sets. Validate simulated patterns for Plant Functional Types, above-ground carbon and

emissions, where possible. Account for discrepancies between simulated & observed! Model Experiments. Address questions concerning climate-vegetation-fire interactions

and emission patterns.

----------------------wish list---------------------------- Simulate seasonal changes in ignition sources e.g. early- vs late- dry season burning in

tropical savannas. Revisit calibration of population density with fire activity for human-caused ignitions.

Consider joint effects of land use change. (Data sources? GLC 2000, Ramankutty-Foley, Goldewijk HYDE 3.0)

Incorporate land use effects directly into the model e.g. grazing (tropical savannas) or deforestation rates (humid tropical forests).

Simulate variability in lightning-caused fires (Data source? Optical Transient Detector, Christian et al. 2003).--------------------------------------------------------

Linking LPJ-SPITFIRE to Remote Sensing Studies of Emissions

Total amount of Emissions (E) typically described by the following equation (Seiler and Crutzen 1980),

M = ∑ ( [A]ijt x [B]ij x [C]ijt x [EF]k), where

• A is the monthly (t) burned area (km2) at location ij;• B is the fuel load (tonnes/km2) expressed ona dry weight (DM) basis; • C is the fraction of available fuel which burns (the combustion factor); and• EF is the Emission Factor for the kth trace species (g/kg or tonnes/km2).

Estimating Total Emissions

Reducing uncertainty in emission estimates• New long-term satellite products becoming available (e.g. GLOBCARBON Plummer et al. in progress, Perriera et al. in progress., Camaro et al. 2005 GCB + many others).• Fine temporal &/or spatially resolved optical (e.g. LANDSAT-TM, MODIS ‘Terra’ & ‘Aqua’, Meteosat) for separate emission calculations and testing above products. But, large uncertainties remain with respect to…

• How much biomass is available for burning through space and time. (Litter production, crown biomass.)

• Relative amount of fine fuels and coarse fuels. (Flaming vs smouldering combustion.)

• Fuel moisture. (Flaming vs smouldering combustion.)

• What proportion of biomass is combusted. (Fire intensity.)

Thank you for your attention

Northern Australia:Observed Number of Fires

(AVHRR FAA data, DOLA)

Northern Australia:Simulated Number of Fires (LPJ-SPITFIRE)

xxxxxxxSiberia & Central Asia:

Simulated Boreal Needleaved Evergreen FPC, 2000 (LPJ-SPITFIRE)

xxxxxxxSiberia & Central Asia:

Simulated C3 grass FPC, 2002 (LPJ-SPITFIRE)

xxxxxxxSiberia & Central Asia:

Simulated Temperate Broadleaved Summergreen FPC, 2002 (LPJ-SPITFIRE)

xxxxxxxSiberia & Central Asia:

Simulated Boreal Broadleaved Summergreen FPC, 2002 (LPJ-SPITFIRE)

xxxxxxxSiberia & Central Asia:

Simulated Boreal Broadleaved Summergreen FPC, 2002 (LPJ-SPITFIRE) expected