James D. Nations
We shall not cease from exploration And the end of all our exploring Will be to arrive where we started And know the place for the first time.
—T.S. ELIOT, “Little Gidding” (1942)
EVERY sixteen days a Landsat satellite passes silently over the tropical landscape of Costa Rica, recording digital data on the rain forests, savannas, rivers, lakes, and mountains that lie 918 kilometers below. The recorded data are a worthless collection of zeros and ones until the scientific mind manipulates them and transforms them into images that have meaning for the future of human beings and the thousands of species that live in the habitats the images depict.
The analysis of remotely sensed images has come a long way from the biplane flights of World War I pilots, who brought back film that inadvertently showed traces of Roman-era ruins in British wheat fields. Seen from the air, the small rises and dips that farmers stepped across could be recognized as the foundations and walls of centuries-old Roman buildings. In the tropics today we find it easier to locate the ruins of ancient civilizations from hundreds of kilometers in space than from a hundred meters through the dense, green screen of the rain forest itself.
Combined with the seeming wizardry of digital mapping technologies, the applications of remote sensing have become enormous: mapping indigenous territories to monitor illegal encroachment, tracing national park boundaries across international boundaries and through unmarked wilderness, identifying wildlife habitat in regions where humans have no easy access, and so forth. The applications of digital images and digital mapping take us out of the realm of guesswork and into the world of the technological future. We are limited ony by our own creativity.
In this volume editors Basil G. Savitsky and Thomas E. Lacher Jr. bring us new and novel applications for this future, including a gap analysis technique