Identification Information Citation Originator: USDA Forest Service, Geospatial Technology and Applications Center, BAER Imagery Support Program Publication Date: 2017-06-27 Title: Burned Area Reflectance Classification (BARC) Data Bundle for the ROUND Fire occurring on the Gila NF - 2017 Publication Information Publication Place: Salt Lake City, Utah, USA Publisher: USDA Forest Service Geospatial Data Presentation Form: raster digital data Description Abstract: These data products are preliminary burn severity assessments derived from Sentinel 2 data. The pre-fire and post-fire subsets included were used to create a differenced Normalized Burn Ratio (dNBR) image. The dNBR image attempts to portray the variation of burn severity within a fire. The severity ratings are influenced by the effects to the canopy. The severity rating is based upon a composite of the severity to the understory (grass, shrub layers), midstory trees and overstory trees. Because there is often a strong correlation between canopy consumption and soil effects, this algorithm works in many cases for BAER teams whose objective is a soil burn severity assessment. It is not, however, appropriate in all ecosystems or fires. It is expected that BAER teams will adjust the thresholds to match field observations to produce a soil burn severity. Purpose: These data were created by the USDA Forest Service Geospatial Technology and Applications Center (GTAC) to support Burned Area Emergency Response (BAER) teams. Product List mask.shp A mask file depicting areas where clouds and cloud shadow obscured accurate representation of burn severity. Active fire is also included in the mask so as not to create false high severity readings. Round burn severity data.kmz Google Earth format file that contains the burn severity (BARC4) layer as well as the perimeter and post-fire reflectance image. s2_20160606_20170621_round_barc4.tif: BARC4, Four category preliminary estimate severity classification. s2_20160606_20170621_round_barc256.tif: BARC256, 256-class (0-255); continuous image representing preliminary estimate of burn severity. This dataset can be adjusted by the user, if needed, to refine the thematic BARC4 product and/or define a new BARC4. It is anticipated that users will adjust the breakpoints between classes, then recode to their desired 3 or 4 classes. s2_20160606_20170621_round_dnbr.tif: Continuous dNBR product scaled by 1000; theoretical range of values is -2000 to 2000 s2_20160606_refl_b12_b8a_b5_clip.tif: Pre-Fire Sentinel 2 reflectance image subset, acquired on 06/06/2016. Band order (1-3): SWIR, NIR, Red (Sentinel 2 bands 12, 8a, 5). prefire_image_S2_20160606.jpeg JPEG version of the prefire Sentinel image s2_20170621_refl_b12_b8a_b5_clip.tif Post-Fire Sentinel 2 reflectance image subset, acquired on 06/21/2017. Band order (1-3): SWIR, NIR, Red (Sentinel 2 bands 12, 8a, 5). postfire_image_S2_20170621.jpeg JPEG version of the postfire Sentinel image BARC256 Thresholds: 0-63 Unburned 64-103 Low 104-165 Moderate 166-255 High All files are projected in UTM Zone 13N, WGS84 Contact: Justin Epting jepting@fs.fed.us (801) 975-3755 ******************************************************************************** The following section should be completed after the BARC has been field validated by the BAER team and this entire metadata file should be returned to GTAC with the Soil Burn Severity data. BAER Assessment Completion Date:8/11/2017 BAER Team GIS Analyst:Brian Park BAER Team Leader:Mike Natharius Soil Burn Severity Analyst(s):Mike Natharius Soil Burn Severity thresholds: Unburned / Undetectable:0-63 Low:64-103 Moderate:104-165 High:166-255 Sequence of steps used to create Soil Burn Severity data: The "RoundFireSeverity_BARC20170621Derived_20170811" feature class is derived from the GTAC BARC dataset, "s2_20170606_20170621_round_barc4.tif." The original BARC4 severity class breaks were also used to generate the soil burn severity data. The class breaks are as follows:0-63 Unchanged, 64-103 Low, 104-165 Moderate, 166-255 High The only adjustment made to the original BARC4 data was to account for 173 acres of no data due to cloud cover and 13 acres of active fire present on the 6/21/2017 post-fire image. The 13 acres of active fire were adjusted by using aerial imagery (2013, 1 ft. resolution) to discern vegetation cover and surrounding areas severity pixels to estimate burn severity. The 173 acres on the northeastern side of the fire obscured by cloud cover was field inspected and the results were manually digitized into the final burn severity (two pockets of moderate severity surrounded by low severity). The following steps were used to generate the "RoundFireSeverity_BARC20170621Derived_20170811" feature class: Reprojected the "s2_20170606_20170621_round_barc4.tif" to NAD 1983 UTM Zone 12, using the Raster Reproject tool; clipped the BARC4 .tif to a 20-meter buffer of the Round Fire 6/20 perimeter, converted the clipped .tiff to a polygon feature class (no Simplify Polygons); performed an Identity on the new polygon class by the no data mask polygons; manually adjusted the active fire no data areas using aerial imagery and nearest severity data, digitized field observation polygons for the area of cloud cover based on field observation; clipped the burn severity polygon feature class to an unbuffered 06/20 perimeter; and finally performed an Identity on the final Round Fire Perimeter (7/6/2017) by the final soil burn severity polygons to account for area of fire growth on the western side of the fire that occurred after the BARC post-fire image - this area was left as "No Data" but was most likely mainly low severity with some unburned and moderate. Additional Comments: