YOSEMITE WILDFIRE ENDANGERS VISITORS IN BACK-COUNTRY

NASA image courtesy Jeff Schmaltz, LANCE/EOSDIS MODIS Rapid Response Team at NASA GSFC. Photo courtesy of Yosemite National Park. Caption by Adam Voiland.

FROM:  NASA  

People come to Yosemite National Park expecting awe-inspiring views and great camping amidst the park’s granite peaks and forested lowlands. In September 2014, some visitors got much more than that.

A small wildfire had been burning in Yosemite for weeks before it suddenly quadrupled in size in early September due to strong winds and high temperatures. Park authorities needed helicopters to evacuate dozens of visitors from back-country locations on September 7, 2014, including 85 climbers airlifted from the summit of Half Dome and approximately 100 hikers picked up from campgrounds in Little Yosemite Valley. Several people posted photographs of the evacuation to social media sites as they were being ferried away.

A NASA satellite orbiting 725 kilometers (450 miles) overhead captured images of the Meadow fire from above on September 7, 2014. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured the top image of wildfire activity in Little Yosemite Valley. Red outlines indicate hot spots where MODIS detected the unusually warm land surface temperatures associated with fires. The lower image was taken by Yosemite National Park staff on September 7, 2014. Half Dome is on the left, with a smoke plume rising from Little Yosemite Valley to its right.

Lightning first ignited the Meadow fire on July 20. For several weeks, park officials let the small, high-altitude (8,000 feet or 2,440 meters) blaze burn in order to preserve the park’s natural fire patterns and because it posed no threat to public safety, according to The Los Angeles Times. Indeed, the fire had burned just 19 acres (8 hectares) over the first 49 days.

Then winds surged on September 7 and the Meadow fire suddenly flared up. By September 8, the fire had charred 2,582 acres (1,044 hectares). Though it is large enough to provoke dramatic photographs from the ground, the fire is small compared to California’s largest fires. For comparison, the Happy Camp Complex fire in northern California has burned more than 99,000 acres and was only partly contained as of the same date.

Visit Worldview, a satellite image-browsing tool maintained by the MODIS Rapid Response Team, to track the fires over time.

References and Related Reading

ABC7News (2014, September 8) Meadow Fire in Yosemite Grows to 2,600 acres. Accessed September 8, 2014.

CAL FIRE (2014, September) Statistics. Accessed September 8, 2014.
Huffington Post (2014, September 7) Half Dome Hikers Evacuated By Helicopter As Wildfire Rages In Yosemite National Park. Accessed September 8, 2014.

The Los Angeles Times (2014, September 7) Fierce winds push Yosemite blaze to 700 acres. Accessed September 8, 2014.

NASA Earth Observatory (2014, September 7) Yosemite’s Granite. Accessed September 8, 2014.

U.S. Drought Monitor (2014, August 19) California. Accessed September 8, 2014.

Yosemite National Park (2014, September 8) Meadow Fire. Accessed September 8, 2014.

NASA image courtesy Jeff Schmaltz, LANCE/EOSDIS MODIS Rapid Response Team at NASA GSFC. Photo courtesy of Yosemite National Park. Caption by Adam Voiland.

THE RIM FIRES

The Rim Fires.  Credit:  NASA

FROM:  NASA 

The Rim Fire in northeastern California continues to burn on the Stanislaus National Forest, Yosemite National Park, and the Bureau of Land Management and State responsibility land.  This fire began on August 17, 2013 and its cause is still currently under investigation.  Over 224 square miles have been affected as of Sunday, August 25.  It is still only 7 percent contained. Inaccessible terrain, strong winds, and dry conditions all present at this fire make for very difficult fire fighting. The ability for this fire to create havoc spreads far and wide, beyond even the area it is consuming.  According to the San Jose Mercury News, "Although the Rim Fire is more than 100 miles from the Bay Area, it still could threaten San Francisco's electric supply if it damages the power system originating in O'Shaughnessy Dam at Hetch Hetchy reservoir."

The latest on the Rim Fire from inciweb.org:  "The Rim incident is expected to continue to exhibit very large fire growth due to extremely dry fuels and inaccessible terrain. Rapid fire growth and extreme fire behavior and hampering suppression efforts. Aerial resources are being effective with MAFFs and VLAT DC-10 air tankers prepping locations in advance of the fires spread toward the Highway 108 corridor and along the eastern perimeter of the fire. The forecasted high winds and high potential for long range spotting however remains a  significant concern for fire to advance beyond the retardant lines and allow for fire spread into the communities of Tuolumne City, Twain Harte and Long Barn to the west of the fire and east into the Hetch Hetchy watershed."

The fire itself is in control of its own weather.  NBC4 in Southern California reports: "Calfornia fire officials say the fire is so large and is burning with such a force, it has created its own weather pattern, making it difficult to predict which direction it will move. 'As the smoke column builds up it breaks down and collapses inside of itself, sending downdrafts and gusts that can go in any direction,'' CalFire spokesman Daniel Berlant told the Associated Press. "There's a lot of potential for this one to continue to grow.'"

Dense smoke from the fire has been a serious health threat as well.  Health officials in Reno, Nevada report the air quality index in their city is in the "unhealthy" range due to the smoke fallout from the Rim Fire. The smoke has also created visibility problems for air ambulance services in the Reno area as well.  The smoke has prevented them from responding to some emergency calls across the region in the last couple of days.