Flames lit by personnel at Bandelier National Monument in New Mexico on May 4, 2000, as part of the Cerro Grande Prescribed Fire plan were supposed to burn away, in a controlled fashion, brush that might otherwise spark a wildfire. Instead those flames started exactly what they were meant to prevent. Winds that the Cerro Grande plan did not take into account fanned the fire into a raging blaze, which had engulfed 235 homes by May 10 and some 45,000 acres of land by May 17.

On May 11, Secretary of the Interior Bruce Babbitt formed a Fire Investigation Team, which uncovered a number of ways in which government officials failed to properly organize and implement the Cerro Grande plan. And now, more information about how the fire spread could emerge from images taken in May by instruments on board NASA's Terra Spacecraft.

Indeed, the Multi-angle Imaging Spectro-Radiometer (MISR)--the first instrument of its kind--produced a series of true-color pictures that show the Los Alamos fire from orbit. As Terra flew from north to south (top to bottom in images below), the instrument's nine digital cameras took pictures of the scene from nine different angles in seven minutes. The three shown at right reveal north-central New Mexico looking 60 degrees forward (top), straight down (middle) and 60 degrees aft (bottom).

The bluish-white smoke plume appears in the left half of all three images just west of the Rio Grande River, but it stands out most prominently in the steep-angle views. So, too, a thin, white water cloud is most visible in the top image in the upper right corner. These features look slightly different from different angles because the instrument is carefully calibrated to measure the brightness, contrast and color of reflected sunlight.

It is this change in reflection that enables scientists to distinguish and monitor different types of atmospheric pollution, including aerosols and particulate matter, and to identify hazes, cloud forms and land surface covers. By combining this information with stereoscopic techniques, they can generate three-dimensional models and estimate how airborne particles affect the earth's climate system.

Initial data from the five instruments on board the Terra satellite, launched on December 18, 1999, were only made available last month, on April 16. Thus, this set of images are among the first to come from MISR. It is hoped that they will also be among the last showing proscribed forest fires gone wrong.

terra pic
Image: NASA/GSFC/JPL, MSIR SCIENCE TEAM