Relative differences Normalized Burn Ratio (RdNBR) burn severity estimates calculated from Visible Infrared Imaging Radiometer Suite (VIIRS) data and HYSPLIT air particle trajectories for the County Line Fire, which burned about 35,000 acres of Florida forest in April 2012.
Team Location: Mobile County Health Department, Mobile, Alabama
Authors:
Walt Clark (University of South Alabama)
Rachael Isphording (Embry-Riddle Aeronautical University)
Rebecca Lanier (University of Southern Mississippi)
Shikher Mishra (University of South Alabama)
Skyler Sampson (University of South Alabama)
Mentors/Advisers:
Bernard Eichold, M.D., Dr.P.H. Mobile County Health Department
Kenton Ross, Ph.D. (NASA, DEVELOP National Science Advisor)
Joe Spruce (Computer Sciences Corp., Stennis Space Center)
Abstract:
As the Southeast region of the United States continues to grow in population, wildfires are increasing as a social, economic, and health concern. Amplifying these concerns, forestry and forest products are currently the leading industries in several Southeastern states. To perform a wide-scale analysis of the diverse effects wildfires have on the Southeast, the NASA DEVELOP Mobile County Health Department (MCHD) team identified recent, significant wildfires within this region to be used as case studies. Relevant data and imagery were downloaded for days before, during, and after each case fire from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors on board Terra and Aqua, the Visible Infrared Imaging Radiometer Suite (VIIRS) sensor on board on the Suomi National Polar-orbiting Partnership (NPP), and the Landsat program’s Thematic Mapper (TM), Enhanced Thematic Mapper Plus (ETM+), and Operational Land Imager (OLI) sensors.
Several fire severity variables were ascertained and compared. The total burn extent, greatest burn temperature, and fire radiative power for each fire were measured. After calculating the Relative differenced Normalized Burn Ratio (RdNBR) for each fire across each different sensor, the RdNBR was compared to the burn extent, temperature, and fire radiative power (FRP) for agreement among different burn metrics and different sensors.
As it is still difficult to ascertain the contributions of fire aerosols to ambient air quality, the MCHD team investigated a method to estimate biomass burned and aerosol contributions. These aerosols were first identified using VIIRS and MODIS aerosol optical depth thickness (AOT) and imagery. The team then estimated the effects the fires had on the AOT data This method approximates the total biomass burned and resultant aerosol loading based on coefficients of smoke aerosol emission rates and MODIS derived fire radiative power (FRP) of the fire in question. Further agreement between the aerosols emitted and other fire severity metrics was analyzed. The results of this research were shared with end-user organizations in the Southeast that could benefit from enhance decision-making tools relating to burn severity.