Environmental Monitoring & Modelling Research Group The operational MSG SEVIRI fire radiative power products generated at the Land-SAF Martin Wooster, Gareth Roberts, Weidong Xu, Patrick Freeborn, Jianping He (Kings College London) Yves Govaerts, Alessio Lattanzio (EUMETSAT)
Introduction Atmospheric monitoring & short-term forecasting requires NRT estimates of biomass burning emissions (E Aer, E CO, E CH4 etc). Emissions of Burnt Emissions Factor of = x Species i (E i,g) Biomass (kg) Species i (EF i, g.kg -1 )
Introduction Atmospheric monitoring & short-term forecasting requires NRT estimates of biomass burning emissions (E Aer, E CO, E CH4 etc). Emissions of Burnt Emissions Factor of = x Species i (E i,g) Biomass (kg) Species i (EF i, g.kg -1 ) Best provided by high frequency EO-based fire detections + an estimate of their emission source strength... modelled AOD observed FRP Meteosat SEVIRI Imagery of Greek Fires (Aug 2007) ECMWF Model Run (J. Kaiser)
Fire Radiative Power& Energy FRP is a measure of the radiative power output of a fire (all λ, all θ v ) Vegetation fuel Thermal camera (λ=3.9 μm) + Optical video camera weather station h=10m Digital scales FRP Fuel Mass 4
Fire Radiative Power& Energy FRP (MW) Fire Fire Radiative Radiative Energy Power (MW) (MJ) Fire Radiative Energy vs. Fuel Mass Burned Burnt Biomass = CF x FRE Combustion Factor (CF) ~ constant Mass loss rate (kg/s) Fuel Fuel Consumption Mass Rate Burned (kg.s(kg) -1 ) Time (secs)
Geostationary Active Fire Detection MIR channel TIR channel MIR-TIR Fire Map
LandSAF FRP Products User consultation (e.g. with ECMWF) determined a strong desire for FRP method to substitute existing emissions methodology, with the requirements of : FRP Pixel Product FRP Gridded Product Active Fire detection at 15 min temporal & 3km spatial resolution FRP calculation from active fire detections NRT 15 30 min after image acquisition Early Fire Detection and Warning Mean FRP at 1hour temporal & 5 spatial resolution NRT ~3 hr after image acquisition Regional Biomass Burning Emissions Modelling
Operational Meteosat FRP Pixel Product : List Dataset Product HDF5_LSASAF_MSG_FRP_ListProduct_<Area>_YYYYMMDDHHMM VARIABLE MEANING UNITS SCALE RANGE Global product generated from FRP pixel FACTOR derived for different dates only as a visual example FRP Pixel FRP MW 10 > 0 Structure: List (one entry per fire) Format: HDF5 Size : ~ 20 Kb FRP_SDEV Pixel FRP Std deviation MW 1 > 0 PIXEL Pixel number Value p.n. 1 [1-3712] LINE Line number Value p.n. 1 [1-3712] BW_NUMPIX Background window number of pixels p.n. 1 [15,215] BW_SIZE Background window Size p.n. 1 [5,15] [1] LATITUDE Pixel Latitude Deg 100 [-90,90] LONGITUDE Pixel Longitude Deg 100 [-180,180] FIRE_CONFIDENCE Pixel Fire Confidence p.n. 100 [0,1] BT_MIR Pixel Fire BT MIR K 10 > 0 BT_TIR Pixel Fire BT TIR K 10 > 0 BW_BT_MIR Background Mean BT MIR K 10 > 0 BW_BTD Background Mean BTD K 10 > 0 PIXEL_SIZE Pixel Size Km 2 100 > 9 PIXEL_VZA Pixel View Zenith Angle Deg 100 [0,90] PIXEL_ATM_TRANS Atmospheric transmission factor p.n. 1000 [0,1] ACQTIME Pixel Acquisition Time Time 1 [0,2359]
Product Operational Meteosat FRP Pixel Product : Quality Dataset VALUE MEANING ---------------------------------------- 0 NOT POT FIRE 1 FRP OK 2 FRP SAT 3 CLOUDY 4 SUN GLINT 5 SUN GLINT RATIO 6 NO BCK 7 BAD BCK 8 CLOUD EDGE 254 NOT PROCESSED Structure: Matrix (pixel level) Format: HDF5 Size : ~ 4.5 Mb HDF5_LSASAF_MSG_FRP_QualityProduct_<Area>_YYYYMMDDHHMM VARIABLE MEANING UNITS SCALE FACTOR RANGE QUALITY FLAG Quality flag p.n. 1 [0,255] QUALITY FLAG coding NAME VALUE MEANING FRP_APL_NOTPOT 0 FRP NOT Estimated: Not a potential fire pixel FRP_APL_FRP 1 FRP Estimated: OK STATUS FRP_APL_FRP_SAT 2 FRP Estimated with at least 1 pixel saturated 3.9 channel FRP_APL_CLOUD 3 FRP NOT Estimated: CLOUDY PIXEL FRP_APL_SUNG 4 FRP NOT Estimated: SUN GLINT NOK FRP_APL_SUNGRATIO 5 FRP NOT Estimated: SUN GLINT CHANNEL RATIO NOK FRP_APL_NOBCK 6 FRP NOT Estimated: NO BACKGROUND FOUND FRP_APL_BCKNOT 7 FRP NOT Estimated: BACKGROUND NOT SIGNIFICANT FRP_APL_CLOUDEDGE 8 FRP NOT Estimated: CLOUD EDGE FRP_APL_NOTPROC 254 FRP NOT Estimated: PIXEL NOT PROCESSED
MODIS and Active SEVIRI Fire Detection MODIS (12:20 GMT) SEVIRI (12:27 GMT) Green : MIR (3.9 µm) channel radiance background Yellow : Detected fire pixels
Validation of FRP Pixel Product Per-fire FRP from SEVIRI (MW) 4000 3500 3000 2500 2000 1500 1000 500 y = 0.97x r² = 0.95, n = 392 bias = -4.3 MW scatter = 91.4 MW rmsd = 91.5 MW Each dot represents a single cluster of fire pixels North Africa South Africa South America Europe 0 0 500 1000 1500 2000 2500 3000 3500 4000 Per-fire FRP from MODIS (MW)
Africa Biomass Combustion Map of 500m MODIS burned area SEVIRI 3km FRP observations Remapped MODIS burned area Field measurements for Savanna 137-528 g.m -2 (Hoffa et al., 1999) 146-404 g.m -2 (Hely et al., 2003) FRP temporal profile derived from the 15 minute temporal resolution SEVIRI AF observations
Diurnal Fire Cycle Meteosat SEVIRI Active Fire Detects Diurnal Variation of Fuel Consumption Rate Roberts, G., Wooster, M.J., and Lagoudakis, E. (2009) Biogeosciences, 6, 849-866.
Continental Africa Biomass Burning Strong seasonal cycle Strong daily fluctuations
Some Limitations of Geostationary FRP FRP underestimation (due to large number of non-detected low FRP fire pixels) FRP underestimation (due to small number of saturated pixels)
Rational for FRP Grid Product 1 1 α c
FRP Grid Product Product Structure: Matrix (Grid Res) Format: HDF5 Size : ~ 850 Kb VARIABLE MEANING UNITS SCALE FACTOR FRP FRP at 5 degree resolution averaged over one hour FRP_RANGE GRIDPIX HDF5_LSASAF_MSG_FRP_Frp_Grid_Global_YYYYMMDDSSEE Difference Max - Min among all FRP grid in the hour Number of SEVIRI pixels used to estimate the BURNTSURF Spatial Res : 5 FRPOBS Real measured FRP (no cloud correction) Temporal Res : 1 Hour NUMIMG Number of images used for the temporal average MW 1 > 0 MW 1 > 0 p.n. 1 > 0 MW 1 >0 p.n. 1 >=0 RANGE FRP is the average over 1h and 5 deg Cell accounting for cloud cover and missed small fires FRP Grid also includes the information about the reason why no fires has been found. The two possible reasons, input data missing and no detected fire in the grid cell: Input Data Not available : 32767 No fires in the grid cell : 0 NUMFIRES BURNTSURF Average number of fires detected in the 5 degree box in one hour Percentage of burnt pixels within the 5 degree box in 1 hour p.n. 10 >= 0 p.n. 100 [0,100] LATITUDE Grid Latitude value Deg 100 [-90,90] LONGITUDE Grid Longitude value Deg 100 [-180,180] CLEARSKYFRAC Factor accounting for the cloud coverage in the 5 degree box, averaged over 1 hour (1 means cloud free) ATMTRANS Average Atmospheric correction factor SMALLFIRES Factor accounting for the signal not retrieved due the fires too small to be detected by SEVIRI p.n. 100 [0,1] p.n. 10000 [0,1] p.n. 100 [0,1]
Validation of Adjustment Factors over Different Regions y=1.04 x R 2 = 0.76 y = 1.02 R 2 = 0.91 Measured Measured Predicted Predicted y = 0.97 R 2 = 0.34 Measured Measured y =1.72 R 2 =0.185 Predicted Predicted
MACC integrated FRP Product Based on real-time FRP Uses SEVIRI 15 minute data Blends with 6hrly MODIS gives global coverage allows detection of lower FRP fires GOES data added shortly 4 hrs behind real-time Global, 125 km spatial res. Daily temporal resolution ~ Hourly under dev. Averaged FRP density [Wm -2 ] in125 km cells This product is the fire emissions driver for the prototype GMES Atmospheric Core Service www.gmes-atmosphere.eu/services/gac/fire/ MACC D-Fire led by J. Kaiser (ECMWF)
FRP to NRT Atmospheric Conc. Emissions (E i ) of trace gases and aerosol species calculated using standard emission factors (EF i ) NRT CO biomass burning tracer (ppb) 2009 Station Fire & Others Emissions of Burnt = x EF i (g.kg -1 ) Species i (E i,g) Biomass (kg) MISR Image NASA JPL Station Fire @ NASA JPL www.gmes-atmosphere.eu/services/gac/nrt/ Modified Combustion Factor (CF) needed to account for large difference from GFED (that represents current best historical estimate) Part of this is to adjust the FRE-derived emissions for cloud cover and undetected low FRP fires (which can be numerous in some areas).
Questions?