Research Review Reveals Limitations to Drought Impact Monitoring
Forests across the United States are under increasing stress from drought, yet researchers and land managers are limited in their ability to efficiently monitor drought impacts from any single data source, concludes a recently published drought monitoring review by Eastern Threat Center scientists. When anticipating drought effects on forests, forest monitors often start with meteorological measures of drought (precipitation and temperature) that were primarily designed for predicting crop stress and yield. Trees and forest ecosystems respond in much more complex ways to drought stress, creating challenges for forest monitors to fully understand and measure drought impacts. Remote sensing methods, such as satellite imaging or aerial surveys, can track drought stress more directly, but these approaches are limited. As an additional complexity, drought can aggravate forest disturbances like bark beetles and fire, so these indirect drought impacts must be recognized as distinct but related. In the review, researchers argue for a more comprehensive “big data” approach that captures meteorological and remote sensing data as well as diverse datasets that cross monitoring scales. Such an approach could help forest monitors contextualize drought impacts and support management and restoration decisions.
Pictured: Multiyear drought can kill trees outright or it can also increase mortality through related bark beetle activity and wildfire. In this aerial photo from California’s 2016 Cedar Fire, all three interrelated factors converge. Photo courtesy of Inciweb.org.
Norman, Steven P.; Koch, Frank H.; Hargrove, William W. 2016. Review of broad-scale drought monitoring of forests: Toward an integrated data mining approach. Forest Ecology and Management 380:346-358.
Contact: Steve Norman