In 1992, the United States government established a program to evaluate the utility of classified U.S. remote sensing capabilities for addressing environmental issues. These sensors provide unique capabilities such as global coverage, high resolution, timely revisits, along with a four decade long archive of observations. Under this program, there are on going efforts to evaluate the capability of classified national systems for obtaining fundamental glacier observations, such as extent, surface velocities, firn-line position, and volume change. Robert A. Bindschadler, a glaciologist with NASA's Goddard Space Flight Center and a member of the Environmental Task Force (ETF), conceived of a glacier mass-balance feasibility study using data from classified systems and, with the author, is leading a joint MEDEA/USGS Project to critically assess the value of classified data sources to support glaciological investigations. Preliminary results indicate that classified systems can provide information not presently attainable from civil systems.

Although the imagery used in these studies remains classified at the present time, a process has been established for the generation and release of imagery derived products (IDP'S)-- unclassified information derived from classified systems. A policy signed in October 1996 allows for the generation and distribution of unclassified information from classified systems. The process for declassifying products is still young, the number of products being approved for release is increasing and expected to become even greater. The USGS glacier program will significantly benefit from this capability through the generation of: (1) terminus-movement maps; (2) flow-rate measurements; (3) firn- line maps; and (4) high resolution glacier digital elevation models for volumetric change determinations.

A program is also being established for obtaining and archiving classified imagery to create a legacy of high quality imagery for the future. Under this program, imagery will be collected at appropriate intervals at a number of environmentally significant sites (termed fiducials) worldwide and archived at the Advanced Systems Center in Reston, VA. Civil agency users with the necessary clearances will have immediate access to the data as it is collected. The USGS has already recommended a number of glacier sites to be included in this program.

Classified systems can play an important role in the future monitoring of glaciers. The fiducials program is a first step in ensuring that a quality record of glacier imagery is available. With the approval of the derived-products policy, all federal agency personnel, with or without clearances can utilize information from classified systems. It is important that any long-term plans for glacier monitoring take advantage of the information provided by these systems. [an error occurred while processing this directive]