Life Histories from Landsat: 25 Years in the Pacific Northwest Forest — North/South Tour
Released on December 7, 2012
This visualization shows a sequence of Landsat-based data in the Pacific Northwest. There is one data set for each year representing an aggregate of the approximate peak of the growing season (around August). The data was created using a sophisticated algorithm called LandTrendr. LandTrendr analyzes 'stacks' of Landsat scenes, looking for statistical trends in the data and filtering out noise. The algorithm evaluated data from more than 1,800 Landsat Thematic Mapper images, nearly 1 Terabyte of raw imagery, to define the life histories of each of more than 336 million pixels on the landscape. The resulting trends identify periods of stability and change that are displayed as colors.
In these false color images, the colors represent types of land; for example, blue areas are forests; orange/yellow areas are agriculture; and, purple areas are urban. Each 'stack' is representative of a Landsat scene. There are 22 stacks stitched together to cover most of the U.S. Pacific Northwest. This processed data is used for science, natural resource management, and education.
We move in to the southwest corner of the data set near Redwood National Park and proceed on a slow tour through a portion of the data set. Time loops from 1984 through 2011 as we move. We move over to Mount Shasta, then up the Cascade Range, passing Crater Lake National Park, the Three Sisters, Mount Jefferson, Mount Hood, Mount Saint Helens, Mount Adams, Mount Rainier, Mount Baker, and the North Cascades National Park. Next we move west over Seattle and pass over Olympic National Park, then we head back south down the Willamette Valley back to Redwood National Park.
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 188.8.131.52.0