Our heart goes out to all of those affected by the recent fires. Since the fires burned, we have been working on curating spatial data related to the fires. A longer-term goal is to acquire imagery and topographic data that will enable our team to update the fine-scale vegetation and habitat map, carbon map, and other data products to post-fire conditions. In the meantime, we are providing a roundup of post-fire datasets, articles, and resources to aid in fire response, assessment, and study. This work is part of an integrated watershed effort led by the Ag and Open and Space District in collaboration with the Sonoma County Water Agency, the Sonoma County Information Systems Department, NOAA, the Regional Water Board, Sonoma RCD, and a multitude of land managers and conservation groups.
Soil Burn Severity Data
Soil burn severity data was produced by the United States Forest Service for the Nuns and Tubbs fires. These data were produced in a two step process that included satellite image analysis of Worldview, Sentinel, and Spot data followed by field validation. We will monitor agency web sites and update links and services as needed.
Debris Flow Likelihood Data
Debris flow likelihood data was produced by USGS. The USGS approach uses empirical models that estimate likehood and volume of post-fire debris flows. The models are based on “historical debris-flow occurrence and magnitude data, rainfall storm conditions, terrain and soils information, and burn severity data” (more on methods here). We have published some of the data as services – specifically the likelihood of landslides (by stream segment and by basin) after a 6mm, 15-minute rainfall event. We will monitor the USGS web site and update links and services as needed.
Landslide Likelihood 4-Pane Viewer
Landslide Likelihood Feature Service (Basins)
Landslide Likelihood Feature Service (Stream Segments)
Landslide Likelihood Data Download (download the full suite of debris-flow probability and volume data from USGS)
The State of California (Calfire) maintains current and historic spatial data for California wildfires. The spatial data, which contains perimeters of fires going back to the 1800s, is distributed and maintained by Calfire’s Fire and Resource Assessment Program (FRAP). The layer contains fire perimeters as polygons, along with associated information including fire name, start date, date of containment, cause of the fire, and more. Calfire’s spatial dataset is publicly available here.
Using Calfire’s data, the Sonoma Land Trust developed a web mapping application that illustrates the history of fire in the region since the middle of the last century. The tool lets you ‘slide through time’ to view fire activity. The application also includes the perimeters of the Tubbs, Nunns, and Pocket fires.
The Sonoma County Agricultural Preservation and Open Space District is working with the Sonoma County Water Agency, Sonoma County ISD, and others to 1) acquire high resolution, 4-band post-fire imagery of all burned areas and 2) to update the county’s high resolution Digital Surface Model (DSM) to reflect postfire conditions. Ultimately, the hope is to collect these data and make them available publicly through county services and via sonomavegmap.org.
In the meantime, the following services and images area available. Note that burned areas and living vegetation are most easily visible in color infrared (CIR) imagery.
- Swipe viewer for comparing pre-fire and post-fire imagery
- Vexcel high res. color infrared (CIR) Service
- Vexcel true color (RGB) Service
- Vexcel Image Service (all bands – R, G, B, and NIR)
- Sonoma County Sheriff’s drone imagery of Coffey Park and Journey’s End
- USGS Hazards Data Distribution System (imagery from fires – download as TIFS)
- Post-fire imagery as tile services (ESRI)
- Relativized Burn Ratio (RBR) as a service
Watershed Emergency Response Team Reports (WERTS)
CalFire published WERTs for each North Bay fire in November 2017. These reports provide an overview of the fire and context about burned area geology, soil, and hydrology. The WERTs focus on burned areas especially at risk of post-fire debris flows and erosion. Download the WERTs at the links below:
Other Post-Fire GIS Data Resources
- Map of burned and damaged structures (updated continuously by crews in the area)
- Permit Sonoma Rapid Evaluation Assessments (RESA) web application
- Publication from U.C. Extension: Recovering from Wildfire: A Guide for California’s Forest Landowners
- Publication from US Forest Service: Post Fire Landscape Assessment: Sampling and Analysis Methods
- Geomac fire perimeters (click on ‘Download Fire Perimeters’); feature service of fire perimeters
- Forest service pamphlet for assessing the survivability of fire-damaged Douglas firs
- Article from the Sonoma Land Trust’s blog on the historic role of fire on our landscape