Lynn Chandler

Goddard Space Flight Center, Greenbelt, Md.

(Phone: 301/614-5562)

David W. Tippets

USDA Forest Service, Odgen, Ut.

(Phone: 801/625-5434)

RELEASE NO: 00-111

There was no Labor Day holiday for firefighters battling dozens
of blazes that
have consumed hundreds of thousands of acres across Montana and Idaho. But
fire officials did get some assistance from an unexpected source as scientists
from NASA, NOAA, the USDA Forest Service and the University of Virginia
teamed up to provide them with new observations of the fires from NASA’s Terra
satellite. This marked the first time data from the recently-launched
spacecraft
were used operationally in a crisis situation.

On Aug. 30 and 31, President Clinton declared parts of both Montana and
Idaho disaster areas due to widespread wildfires. On Sept. 1, scientists from
NASA’s Goddard Space Flight Center (Greenbelt, Md.) and NOAA began
providing Forest Service officials with daily images acquired over
those states by
Terra’s Moderate-resolution Imaging Spectroradiometer (MODIS) instrument.

According to Wei Min Hao, project leader of the Fire Sciences
Laboratory for
the Forest Service’s Rocky Mountain Research Station, MODIS data helped
firefighters pinpoint where the fires were burning, where there were still-
smoldering burn scars, and where smoke from the blazes was spreading.

“On days when there is heavy smoke, observers in reconnaissance planes
are unable to see the fire through the smoke,” says Hao. “So we must rely on
thermal infrared sensors and satellite imagery. During this historic
fire season
there are so many fires over such a large area and we have such limited
resources, without the satellite images we could not see the real extent of the
fires and know where to allocate firefighting resources”

According to Hao, satellite images from MODIS and NOAA’s Advanced Very
High Resolution Radiometer (AVHRR) provided a quick overview of where the
fires were most active on the previous day. This information helped the
firefighters plan each day’s strategy and decide how to allocate resources for
monitoring and if necessary battling the blazes.

Terra Project Scientist Yoram Kaufman explains that the MODIS sensor
observes the fire region in 36 different wavelengths of the spectrum,
ranging from
visible to thermal infrared light, so it has the capacity to see
through the smoke in
the atmosphere to detect hot flames on the surface. MODIS also has new
channels that enable scientists to distinguish flaming fires from
still-smoldering
burn scars.

“MODIS can detect smoke at a resolution four times greater than AVHRR
(NOAA’s heritage instrument for MODIS), and MODIS uses several spectral
channels in the solar spectrum so it can see the smoke more clearly,” says
Kaufman. “MODIS can also see burn scars at resolutions as high as 250
meters.”

“Ultimately, this is good for the people at the fire fighting
command center,”
adds Hao. “The MODIS data helps them monitor smoke dispersion, which is a
critical issue for the health of those living in the area.”

According to Chris Justice, MODIS Land Discipline Group Leader and
research professor at the University of Virginia, MODIS will also
make important
new contributions to monitoring fires on a global scale by helping
scientists better
gauge how much gas and aerosol particles they emit every year. In the U.S.
alone, more than 6 million acres have burned this year, which is 2.5 times the
annual average.

Preliminary calculations by Stefania Korontzi (UVa), a member of the MODIS
fire group, estimate that the fires this summer in Montana, Idaho, Nevada, and
Utah have released approximately 76 teragrams (76 million metric tons) of
carbon dioxide. Annual estimates from the USFWS for the entire United States,
averaged from 1988-96, range from 33 to 189 teragrams (33 to 189 million metric
tons) of carbon dioxide that are released by wildfires each year.

“These preliminary calculations show that the emissions from
these wildfires
are significant,” says Justice. “The MODIS fire group will be developing better
estimates of emissions in the coming months, using MODIS data to provide
estimates of the total area burned. The improved spatial resolution
and spectral
band selection of MODIS allows improved mapping of burn scars.”

One advantage Terra had in observing the fires is that it orbits
over the area
in the morning, Hao said. MODIS tends to get more shots of the fires than
NOAA’s AVHRR instrument, which flies over in the afternoon because there is
typically less cloud cover in the morning. Using the two satellites
in tandem gives
firefighters the best possible chance of getting unobstructed views
of the fires.

“It is very exciting that new satellite technology, as manifest
in the MODIS
instrument on Terra, can be used not only to do new Earth system
science, but it
can also be used to help monitor wildfires, save lives and property,
and monitor
air quality,” says Kaufman.

Kaufman says this is the first time Terra data have been made available
operationally. He says the MODIS Team, based at Goddard Space Flight Center,
is making the data available on an experimental basis.

“We are testing our ability to deliver the data operationally
within 24 hours of
acquisition,” he explains. “We hope to be able to deliver the data
operationally in
the future using MODIS’ direct broadcast capabilities.”

Any agency or organization that has a proper receiving station can freely
receive direct broadcast MODIS data every time the satellite flies overhead.
Moreover, a copy of the MODIS sensor will also launch in December 2000
aboard Aqua, Terra’s sister satellite. Once both sensors are in
orbit, MODIS will
see any given place on the Earth’s surface as often as four times per day.

For access to the images and animations from this press release,
visit NASA’s
Earth Observatory web site at http://earthobservatory.nasa.gov.