1. Land cover & fire at high latitudes: model-data comparison and model modification NCEO Land Science Meeting, 28-29 February 2012, Sheffield, UK E.Kantzas, M. Lomas, S.Quegan National Centre for Earth Observation-CTCD University of Sheffield

2. MONitoring and Assessing Regional Climate change in High latitudes and the Arctic. Generate an information package of multidisciplinary ECVs associated with terrestrial carbon and water fluxes at high latitudes. Essential Climate Variables Considered Vegetation CoverOcean Color FireSea Ice Drift River DischargeSurface Wind Snow CoverPCO2, ocean PermafrostPCO2, atmosphere Ice Sheets & GlaciersSea Ice Extent Sea LevelSea Ice Thickness CurrentsSea Surface Temperature Goals: i)Synthesize available data sets ii)Generation of time series iii)Interface ECVs with models

3. NBP LEACHED Litter Disturbance ATMOSPHERIC CO 2 BIOPHYSICS Soil Photosynthesis GROWTH Biomass GPPNPP Thinning Mortality Fire

4. Differences in Net Biome Production between the 3 models in Magnitude Spatial distribution Trend

5. N. America GlobCover GLC2000 Significant differences exist between data sets. Translating land classes into model PFTs is liable to user interpretation.

6. Driving model with different land cover data sets had the following carbon effects: Up to 50% differences in fire emissions Up to 20% differences in net carbon uptake

7. Models cannot capture the temporal and spatial variability of fire which leads to: Underestimation of inter-annual variability of land-atmosphere carbon exchange Inability of models to simulate the effects of fire disturbance on permafrost.

9. Method: By adding a probabilistic component to the algorithm which controls fire occurrence, simulated fire regime resembled GFED data. Due to the lack of an energy balance model no feedbacks of fire disturbance were observed on permafrost despite fire events removing up to 30% of cover.

10. Method: For each site the GFED data variance was added to model variance which lead to the model exhibiting similar variability to data. Burned Area Mhc Fire emissions variance increased but the inter-annual variability of NBP remained largely unaffected.

11. LPJ-WMCLM4CNSDGVM Fuel loadAgB, BgB, litter AgB only Combustion completeness Biomass: 100% Litter: 100% Leaves and fine roots: 100% Stem, coarse roots: 20% Litter: 100% Woody Debris: 40% Biomass: 80%

12. Stocks (PgC)LPJ-WMCLM4CN Biomass9375 Litter10021 Emissions (TgC y -1 )LPJ-WMCLM4CN Biomass290118 Litter37246

13. N. America Eurasia

14. Driving a model with different land cover significantly affects fire emissions and to some extent carbon uptake in boreal latitudes. The spatial and temporal variability in fire occurrence at high latitudes is not captured by C models so fire-permafrost interactions are not simulated. Different process representations lead to radically different total fire emissions and emissions per unit burnt area. Improve parameterization of the probabilistic component in the fire algorithm to better describe the inter-annual and spatial variability of fire emissions and land- atmosphere carbon exchange. Define first qualitatively and then quantitatively modelled fire emissions. After establishing a realistic fire disturbance framework, evaluate fire-permafrost interactions.