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Use of Remote Sensing Data for Delineation of Wildland Fire Effects
Presented by: Jason Adams
Spatial Database Administrator
Yukon Wildland Fire Management
Remote Sensing Platforms
• MODIS (Moderate Resolution Imaging Spectroradiometer)
• LandSAT TM/ETM (Thematic Mapper)
• SPOT Image
• QuickBird
• Airborne GPS
Background Information
0
10
20
30
40
50
60
70
80
90
Reflectance Value
(rescaled)
Band 1 Band 2 Band 3 Band 4 Band 5 Band 7
Landsat Band #
Landsat Band Reflectance Difference: Burned vs. Unburned areas
Unburned
Burned
Red = Band 7 (mid-IR)Green = Band 4 (near-IR)Blue = Band 3 (visual red)
MODIS Platform
• There are two main products of the MODIS program employed by WFM.– Hotspot data (Thermal)– False colour imagery (Reflected Infrared)
Using MODIS Hotspot Data
Modis HotspotData on Internet
Downloadand
Extract
Convertfrom Exchange
to Shapefile
Clip, Buffer out,Buffer back
and Clip again
ClassicGeoprocessing
PolygonsCreatedforMap Display
GIS LaunchedforCartographic
Manipulation
Approximate SizeGrowthRate
Using MODIS Hotspot Data
Modis HotspotData on Internet
Downloadand
Extract
Convertfrom Exchange
to Shapefile
Clip, Buffer out,Buffer back
and Clip again
ClassicGeoprocessing
PolygonsCreatedforMap Display
GIS LaunchedforCartographic
Manipulation
Approximate SizeGrowthRate
Using MODIS Hotspot Data
Modis HotspotData on Internet
Downloadand
Extract
Convertfrom Exchange
to Shapefile
Clip, Buffer out,Buffer back
and Clip again
ClassicGeoprocessing
PolygonsCreatedforMap Display
GIS LaunchedforCartographic
Manipulation
Approximate SizeGrowthRate
SPOT Image
• 10m SPOT Imagery• Black indicates burn
area, red indicates healthy vegetation (Similar to IR Photo)
• Heads up digitized on tablet PC running ArcMap
Quickbird
• In 2007 this image was acquired along the Dempster Highway and contained part of a 2007 fire.
• Testing phase for uses in delineation of fire effects.
LandSAT TM
• Overview of 2007 fire DA-11 in a 7-4-3 LandSAT TM band combination
• Detail shown at level used for Heads-up digitizing.
• Scene Level View, DA-11 seen in bottom left quadrant.
• Even light cloud cover is still valuable.
Comparison of Methods
• Fire BC-03-2006• MODIS Hotspot Buffer• GPS Perimeter• LandSAT Perimeter• Comparison in detail
Burn Severity & LandSAT
Landsat Pre and Postfire Views of the Herron River Fire, DENA 2001
TM4 – TM7NBR =
TM4 + TM7
Burn Severity & LandSAT
• WFM has run a trial with dNBR
• Some challenges are faced.
• Could lead to automated fire poly generation with some GIS processing.
• No field verification program, see challenges above.
Airborne GPS
• Becoming rare for use as final mapping as cost and accuracy of hyper-spectral satellite imagery is becoming lower, soon to be free (LandSAT).
• Mainly used on campaign fires where data is needed right away.
• Although accuracy is “better” on GPS units then a 30m pixel LandSAT image the method of collection (flying around in a helicopter) compromises this. Picture an intoxicated individual walking a line.
! .
5 m
Legend
!. Center of Observations
Typical 6m EPE
1st Std Dev Spatial Ellipse
1st Std Dev Spatial Ellipse (15min int)
PDOP (Positional Dilution of Precision)
< -0.50 Std. Dev.
-0.50 - 0.50 Std. Dev.
0.50 - 1.5 Std. Dev.
1.5 - 2.5 Std. Dev.
> 2.5 Std. De
GPS Accuracy
Three hour plot of stationary GPS, differentially corrected
Airborne GPSReal World exampleBC-03-06
Pre Fire LandSAT ScenePre Fire LandSAT Scene with GPS TrackPost Fire LandSAT ScenePost Fire LandSAT Scene with GPS TrackPost Fire LandSAT Scene with GPS Track (blue) and RS digitized perimeter (yellow)
Comparison of GPS Track (blue) and RS digitized perimeter (black)
Methodologies
• Primary method of fire effects (perimeter) data capture is via digitizing hyperspectral imagery on tablet PC.
• Secondary method is GPS capture
• Future methods to use hyperspectral data and dNBR, this will give both perimeter and severity data.
Conclusions
• Given the size of the Yukon and staffing level, Remote Sensing is the ONLY option for collection of fire data.
• For present time LandSAT is perfectly adequate, SPOT shows a gain is precision but would be cost prohibitive.
• Quickbird is interesting however would probably be only used for WUI or large scale mapping of culturally/ecologically significant targets