Image of the Day: Nighttime satellite view of California’s Rim Fire encroaching on Yosemite National Park

By Holli Riebeek
26 August 2013
(NASA) – The winter of 2013 was among the driest on record for California, setting the stage for an active fire season. By August 26, the Rim Fire had made its way into the record books. At just 15 percent contained, the fire is now the 13th largest in California since records began in 1932. Apart from being large, the fire is also threatening one of the United States’ greatest natural treasures: Yosemite National Park. The Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi NPP satellite tracked the growth of the fire between August 23 and August 26 in this series of nighttime images. The VIIRS day-night band is extremely sensitive to low light, making it possible to see the fire front from space. The brightest, most intense parts of the fire glow white, exceeding the brightness of the lights of Reno, Nevada to the north. Pale gray smoke streams north away from the fire throughout the sequence. The perimeter of the fire grows from day to day along different fronts, depending on winds and fire fighting efforts. On August 24, fire fighters focused their efforts on containing the western edge of the fire to prevent it from burning into Tuolumne City and the populated Highway 108 corridor. They also fought the eastern edge of the fire to protect Yosemite National Park. These efforts are evident in the image: Between August 23 and 24, the eastern edge of the fire held steady, and the western edge receded. The fire grew in the southeast. On the morning of August 25 fire managers reported that the fire was growing in the north and east. In the image, the most intense activity is just inside Yosemite National Park. Fire fighters reported that the Rim Fire continued to be extremely active on its eastern front on the morning of August 26, and this activity is visible in the image. By 8:00 a.m., the fire had burned 149,780 acres. The fire forced firefighters in Yosemite National Park to take measures to protect the Merced and Tuolumne Groves of Giant Sequoias, but the National Park Service reported that the trees were not in imminent danger. While parts of the park are closed, webcams show that most of the park has not been impacted. The Rim Fire started on the afternoon of August 17. It has destroyed 23 structures and threatened 4,500 other buildings. Its cause is under investigation.