Identification_Information: Citation: Citation_Information: Originator: USGS EROS Publication_Date: 12/13/2016 Title: Chimney Tops 2 fire (Version 3 Final), located near Gatlinburg, TN. Geospatial_Data_Presentation_Form: raster digital data Publication_Information: Publication_Place: Sioux Falls, South Dakota USA Publisher: U.S. Geological Survey Online_Linkage: http://edc.usgs.gov Description: Abstract: 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, accurate in all ecosystems or fires. Purpose: These data were created by USGS EROS to support Burned Area Emergency Response (BAER) teams. Supplemental_Information: Fire Name: Chimney Tops 2 Agency: NPS Land Management Unit: Great Smoky Mountain NP (TN) Type of assessment: Immediate Response (BARC) Fire size (acres) as listed on the Situation Report: 17.006 100% contained Pre-Fire Landsat Path/Row and Date: Landsat 8 019/035, 12/03/2015 Post-Fire EO-1 ALI Path/Row and Date: EO-1 ALI 019/035, 12/11/2016 Output Dataset Projection: UTM UTM Zone: 17 Spheroid Name: WGS84 Datum: WGS84 Product List: chimneytops2_v3_pre754_20151203_l8.img = Pre-Fire Landsat scene. chimneytops2_v3_post10-6-5_20161211_ali.img = Post-Fire EO-1 ALI scene. chimneytops2_v3_barc256_20161211ali-20151203l8_clipbox0_nodata255.img = 256-class (0-255) continuous image representing fire severity. This dataset is meant to be adjusted if thevBARC4 does not provide a good estimate of fire severity. It is anticipated that users will adjust the breakpoints between classes, then recode to their desired 3 or 4 classes. chimneytops2_v3_dnbr1000_20161211ali-20151203l8.img = full precision dNBR image in ERDAS Imagine format. chimneytops2_v3_barc4_20161211ali-20151203l8_clipbox0_nodata6.img = Four category severity classification subset in ERDAS Imagine format with values: 0 = background/fill 1 = unchanged / very low (Dark Green) 2 = low severity (Cyan) 3 = moderate severity (Yellow) 4 = high severity (Red) 5 = enhanced greenness 6 = No Data (clouds, shadow, data gaps, etc.) Note: The post and pre fire images had excessive terrain shadows due to low sun angles. Those areas were masked as "no data" to values of 6 for the BARC4 and 255 for the BARC256 images. Time_Period_of_Content: Time_Period_Information: Multiple_Dates/Times: Single_Date/Time: Calendar_Date: Single_Date/Time: Calendar_Date: Currentness_Reference: ground condition Status: Progress: Evaluation of methods in process Maintenance_and_Update_Frequency: As needed Keywords: Theme: Theme_Keyword_Thesaurus: none Theme_Keyword: Wildland Fire Theme_Keyword: Normalized Burn Ratio (NBR) Theme_Keyword: Fire Severity Theme_Keyword: USGS EROS Theme_Keyword: Landsat Place: Place_Keyword_Thesaurus: none Place_Keyword: Gatlinburg Place_Keyword: TN Access_Constraints: FTP data sets are available to any user. Use_Constraints: There are no restrictions on use, except for reasonable and proper acknowledgement of information sources. Data_Set_Credit: USGS EROS Native_Data_Set_Environment: ERDAS Imagine, ARCInfo Data_Quality_Information: Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: These data were terrain corrected using a USGS digital elevation model with less than 1/2 pixel RMS error. Lineage: Process_Step: Process_Description: These data products are derived from satellite imagery. Pre-fire and post-fire scenes are analyzed to create a differenced Normalized Burn Ratio (dNBR) image. The dNBR image portrays the variation of burn severity within the fire. The pre- and post-fire Landsat images are terrain corrected and corrected to Top of Atmosphere reflectance. The Normalized Burn Ratio (NBR) is computed for each date of imagery (Landsat 8 bands) using the following formula: (Band 5(NIR) - Band 7(SWIR) / (Band 5 + Band 7) = NBR (Note: EO-1 ALI Bands 10 (SWIR) & 6 (NIR)) The Differenced NBR is computed to determine severity by subtracting the post-fire NBR from the pre-fire NBR: (PreNBR - PostNBR) = dNBR The BARC products are a generalization of the raw dNBR dataset. Both BARC products have been resampled to unsigned 8-bit images and are easily viewed and adjusted within ArcGIS. The classes represented on the BARC products are created with thresholds chosen by an analyst at USGS EROS. These thresholds can be roughly related back to original dNBR values by multiplying by 5 and then subtracting 275 (for example, a BARC256 value of 100 would relate to a dNBR value of 225). The thresholds used on this particular fire are: Unchanged: All values 0 - 75 Low: All values 76 - 109 Moderate: All values 110 - 187 High: All values 188 - 254 No Data/Clouds: All values 255 General descriptions of the severity classes are below: Unchanged: This means the area after the fire was indistinguishable from pre-fire conditions. This does not always indicate the area did not burn. Low: This severity class represents areas of surface fire with little change in cover and little mortality of the dominant vegetation. Moderate: This severity class is between low and high and means there is a mixture of effects on the dominant vegetation. High: This severity class represents areas where the canopy has high to complete consumption. Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Vertical_Count: 1 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal_Transverse_Mercator: UTM_Zone_Number: Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: row and column Coordinate_Representation: Abscissa_Resolution: Ordinate_Resolution: Planar_Distance_Units: meters Geodetic_Model: Horizontal_Datum_Name: Ellipsoid_Name: Semi-major_Axis: Denominator_of_Flattening_Ratio: Distribution_Information: Resource_Description: Downloadable Data Metadata_Reference_Information: Metadata_Date: 12/13/2016 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: USGS EROS Contact_Person: Randy McKinley Contact_Address: Address_Type: 47914 252nd St City: Sioux Falls State_or_Province: SD Postal_Code: 57198 Contact_Voice_Telephone: 605-594-2745