Burn Severity Assessment With Satellite Remote Sensing

Each year, wildland fires burn millions of acres of America's forests, shrub lands, and grasslands. Vaiations in burn severity and effects of fire are functions of landscape and ecoswystem diversity. Understanding such variations in relationship to land management practices requires the collection of large quantities of geospatial data following major fires. Systematic satellite mapping with calibrated algorithms can deliver reliable information about burn perimeter and variations in burn severity.

The U.S. Geological Survey (USGS) is responding to fire science and management communities' needs for techniques, data, and map products in support of cohesive fire management prioritization and planning across the country. These burn severity data products can be used along with the National Elevantion Dataset (NED), available from the USGS EROS Data Center at http://gisdata.usgs.net/ned/

NPS-USGS National Burn Severity Mapping Project

A cooperative project between the National Park Service and the U.S. Geological Survey has developed the capability to routinely map burn severity patterns and changes over time within a fire and deliver standardized map products to NPS park managers and fire ecologists.

Research on the Satellite Estimation of Burn Severity

The Joint Fire Science Program is supporting a research activity on satellite mapping of burn severity. This research is highly relevant to both science and land management communities, as it seeks to evaluate a robust, consistent burn-severity mapping algorithm for baseline inventory and mapping. By validating the mapping algorithm in different ecosystems throughout the country, with different fire histories, and vegetation effects over time, we ensure a sound science basis for our overall goal of an operational, standardized burn area mapping in support of land management and scientific investigation.

Current Fire Mapping Activities

Abstract

Fire history is an important consideration in any fire or land management planning process. The National Park Service and the U. S. Geological Survey developed a technique to quickly map burn severity using temporal analysis of satellite data. As a pilot study, a burn severity atlas was developed for the Mesa Verde National Park, which experienced major fires in 1959, 1972, 1989, 1996, 2000 and 2002. Historical Landsat data acquired in 1973, 1989, 1996, 2000, and 2002 were used to compile the atlas.

Moccasin Mesa & Rock Springs fire: 1972; Landsat MSS, 1973

Long Mesa fire; 1989, Landsat TM 1990

Chapin 5 fire; 1996, Landsat TM 1997

Pony & Bircher fires; 2000, Landsat TM 2000

Long Mesa fire; 2002, Landsat TM 2002

Discussion

Improved understanding of fire history provides officials the opportunity to better manage a park’s landscape. A number of management practices can benefit from a fire atlas:

• Fire atlas can be used to plan hazardous fuel reduction
• It is useful for assessing impacts and monitoring ecosystem restoration
• Firefighting safety can be enhanced by identifying safe zones
• It can be used as a visual tool to educate the public about fire, fire history, and its effects.
• It provides a quick overview of the extent of the fire and an assessment of the relative severity of fire-effects within the fire perimeter.
• The data is useful for determination of consistency of burn severity thresholds (i.e. burned/non-burned, low, medium, high, severe) for fires from different ecosystems.

Burn Mapping Application

Satellite data analysis was used to derive this color-coded image of burn severity on the Bircher and Pony fires. Note how the (larger) Bircher fire was controlled on the west by the 1996 Chapin fire and, the reduced severity within the perimeters of previous fires (Moccasin Mesa, 1972 and Morefield, 1959). These observations show that historical fires affect the behavior and intensity of subsequent fires. Also note areas within the Morefield fire that burned at higher severity. The perimeter only shows the extent of the fire and not the severity within it. This information is of important when planning fire fighting safety zones.