Four Mile Canyon Fire Soil Burn Severity

Frequently-anticipated questions:


What does this data set describe?

Title: raster.RASTER.FIRE_FOURMILECANYON_BARC256_DNDVI
Abstract:
These data products are derived from Landsat Thematic Mapper 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, accurate in all ecosystems or fires. Boulder County has converted this data from raster format to vector format.
Supplemental_Information:
Fire Name: Four Mile Canyon Fire Agency: USFS Land Management Unit: Type of assessment: Immediate Response (BARC) Fire size (acres) as listed on the Situation Report: 6,250 (9/13/10) Pre-Fire Landsat Path/Row and Date: Landsat 5; 34/32, 090821 Post-Fire Landsat Path/Row and Date: Mosaic of Landsat 7 (33/32) 100910 and Landsat 7 (3432) 100917 Output Dataset Projection: UTM UTM Zone: 13 Spheroid Name: GRS1980 Datum: NAD83
Product List:
fourmilecanyon2_pre743_3432_090821_l5_utm.img = Pre-Fire Landsat reflectance at sensor data subset, scaled by 400 and converted to integer (bands 743(RGB) ERDAS Imagine format)
fourmilecanyon2_post743_3432-100917-3332-100910_l7_utm.img = Post-Fire Landsat reflectance at sensor data subset, scaled by 400 and converted to integer (bands 743 (RGB) ERDAS Imagine format)
fourmilecanyon2_barc256_100917-100910_100821_utm_clip.img = 256-class (0-255) continuous image representing fire severity. This dataset is meant to be adjusted if the BARC4 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.
  1. How should this data set be cited?

    EROS, USGS, 9/18/2010, raster.RASTER.FIRE_FOURMILECANYON_BARC256_DNDVI: U.S. Geological Survey, Sioux Falls, South Dakota USA.

    Online Links:

    • Server=regis1; Service=5152; User=raster; Version=sde.DEFAULT

  2. What geographic area does the data set cover?

    West_Bounding_Coordinate: -105.429884
    East_Bounding_Coordinate: -105.340226
    North_Bounding_Coordinate: 40.078432
    South_Bounding_Coordinate: 40.020024

  3. What does it look like?

  4. Does the data set describe conditions during a particular time period?

    Calendar_Date: REQUIRED: The year (and optionally month, or month and day) for which the data set corresponds to the ground.
    Currentness_Reference:
    REQUIRED: The basis on which the time period of content information is determined.

  5. What is the general form of this data set?

    Geospatial_Data_Presentation_Form: SDE raster digital data

  6. How does the data set represent geographic features?

    1. How are geographic features stored in the data set?

      This is a Raster data set. It contains the following raster data types:

      • Dimensions 215 x 254 x 1, type Pixel

    2. What coordinate system is used to represent geographic features?

      Grid_Coordinate_System_Name: Universal Transverse Mercator
      Universal_Transverse_Mercator:
      UTM_Zone_Number: 13
      Transverse_Mercator:
      Scale_Factor_at_Central_Meridian: 0.999600
      Longitude_of_Central_Meridian: -105.000000
      Latitude_of_Projection_Origin: 0.000000
      False_Easting: 500000.000000
      False_Northing: 0.000000

      Planar coordinates are encoded using row and column
      Abscissae (x-coordinates) are specified to the nearest 30.000000
      Ordinates (y-coordinates) are specified to the nearest 30.000000
      Planar coordinates are specified in meters

      The horizontal datum used is North American Datum of 1983.
      The ellipsoid used is Geodetic Reference System 80.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257222.

      Vertical_Coordinate_System_Definition:
      Altitude_System_Definition:
      Altitude_Resolution: 1.000000
      Altitude_Encoding_Method:
      Explicit elevation coordinate included with horizontal coordinates

  7. How does the data set describe geographic features?

    raster.RASTER.SDE_VAT_59

    OBJECTID
    Internal feature number. (Source: ESRI)

    Sequential unique whole numbers that are automatically generated.

    Value

    Count_

    Red

    Green

    Blue

    Opacity


Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)

  2. Who also contributed to the data set?

  3. To whom should users address questions about the data?


Why was the data set created?

These data were created by USGS EROS to support Burned Area Emergency Response (BAER) teams.


How was the data set created?

  1. From what previous works were the data drawn?

  2. How were the data generated, processed, and modified?

    (process 1 of 2)
    These data products are derived from Landsat Thematic Mapper data. 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 further processed to convert bands 1-5 and 7 to at-sensor-reflectance. The Normalized Burn Ratio (NBR) is computed for each date of imagery using the following formula: (Band 4 - Band 7) / (Band 4 + Band 7) = NBR
    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:

    Date: 14-Oct-2010 (process 2 of 2)
    Metadata imported.

    Data sources used in this process:

    • C:\DOCUME~1\mmullane\LOCALS~1\Temp\xml7DCE.tmp

  3. What similar or related data should the user be aware of?


How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?

  2. How accurate are the geographic locations?

    These data were terrain corrected using a USGS digital elevation model with less than 1/2 pixel RMS error.

  3. How accurate are the heights or depths?

  4. Where are the gaps in the data? What is missing?

  5. How consistent are the relationships among the observations, including topology?


How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

  1. Who distributes the data set?[Distributor contact information not provided.]

  2. What's the catalog number I need to order this data set?

    Downloadable Data

  3. What legal disclaimers am I supposed to read?

  4. How can I download or order the data?


Who wrote the metadata?

Dates:
Last modified: 14-Oct-2010
Metadata author:
USGS EROS
c/o Randy McKinley
Sioux Falls, SD 57198

605-594-2745 (voice)

Metadata standard:
FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)
Metadata extensions used:


Generated by mp version 2.9.6 on Thu Feb 24 10:22:45 2011