Global Forest Disturbance Alert System

The Global Forest Disturbance Alert System (GloFDAS) provides data on forest disturbance globally on a quarterly basis.

Reliable maps of global forest cover change are frequently years out-of-date. Consequently, there is a pressing need to develop techniques for monitoring and verifying land cover change and forest disturbances in a timely, low-cost, and accurate manner. Satellite remote sensing from instruments such as NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) offers a consistent and cost-effective method for mapping forest cover change. MODIS data are obtained freely with global daily cover products.

A new MODIS product called the "Quarterly Indicator of Cover Change" (QUICC) has been developed at NASA Ames Research Center by the CASA ecosystem modeling team. The QUICC product is based on comparison of MODIS global vegetation index images at the exact same time period each year (ending of March, June, September, and December) in consecutive years. The CASA team updates its global QUICC products as soon as the newest quarterly MODIS worldwide VI image at 5-km spatial resolution is available.

+ Additional details >>

• Forest disturbance locations are shown as center points of 5 km x 5 km areas that were detected with a significant loss of forest greenness cover (greater than 40%) over the previous 12 months. [see example]
• The cause(s) of any forest disturbance point detected in this map has yet to be confirmed.
• Disturbance locations and impacts are subject to verification through local observations.
• Due to atmospheric interference with satellite image quality, the providers of this forest disturbance data set can make no global assurances of its accuracy.
• For more information on development of these forest disturbance products, visit geo.arc.nasa.gov/sge/casa/latest.html.
• The global validation of the QUICC approach for accurate detection of large-scale tropical forest loss is published in Potter, C. S., 2014, Global Assessment of Damage to Coastal Ecosystem Vegetation from Tropical Storms, Remote Sensing Letters, (in press).

+ Feedback >>

GloFDAS is a collaborative research project. We are therefore interested in information from users on the most probable causes of any given forest disturbance point. If you have information, please contact us

Alternatively if you have suggestions on how to improve GloFDAS, please contact us.

+ Alert system >>

In coming months, GloFDAS will offer an alert system whereby users can sign up to get notifications via email or SMS text message on recent changes in forest cover for a specified location or country.

GloFDAS is done in partnership with Cal State Monterey Bay and NASA Ames Research Center.