NCAR Analysis Shows Widespread Pollution from 2004 Wildfires

Jun 29, 2005

Wildfires in Alaska and Canada in 2004 emitted about as much carbon monoxide as did human-related activities in the continental United States during the same time period, according to new research by the National Center for Atmospheric Research (NCAR). The fires also increased atmospheric concentrations of ground-level ozone across much of the Northern Hemisphere.

The NCAR study, which indicates the extent to which wildfires contribute to atmospheric pollution, was published this month in Geophysical Research Letters. The researchers used a novel combination of observing instruments, computer models, and numerical techniques that allowed them to distinguish between carbon monoxide coming from the wildfires and from other sources.

The team concluded that the Alaskan and Canadian wildfires emitted about 30 teragrams of carbon monoxide from June through August of last year. Because of the wildfires, ground-level concentrations of ozone increased by 25% or more in parts of the northern continental United States and by 10% as far away as Europe.

"It is important to see how the influence of these fires can reach large parts of the atmosphere, perhaps even over the entire Northern Hemisphere," says NCAR scientist Gabriele Pfister, the study's lead author. "This has significant implications as societies take steps to improve air quality."

Carbon monoxide, a toxic gas that can affect human health even at low levels, is emitted by wildfires as well as by motor vehicles, industrial facilities, and other sources that do not completely burn carbon-containing fuels. Ground-level ozone, which affects human health in addition to damaging plants and influencing climate, is formed from reactions involving atmospheric pollutants, including carbon monoxide, in the presence of sunlight. Both pollutants are monitored by the Environmental Protection Agency. However, scientists have been unable to precisely determine regional emissions of carbon monoxide or the extent to which human and natural activities contribute to atmospheric concentrations of the gas.


Image: This MOPITT image shows plumes of carbon monoxide streaming from Alaskan fires across North America and the Atlantic during mid-July 2004. (Image courtesy the NCAR MOPITT Team.)

Wildfires in Alaska and western Canada were particularly intense in the summer of 2004, largely because of unusually warm and dry weather. To quantify carbon monoxide emissions from the fires, the research team used a remote sensing instrument known as MOPITT (Measurements of Pollution in the Troposphere) that is operated by NCAR and the University of Toronto and flown on NASA's Terra satellite. The scientists simulated the transport of the pollutants emitted by the fires and the resulting production of ozone with an NCAR computer model called MOZART (Model for Ozone and Related Chemical Tracers).

The team confirmed its results by using numerical techniques to compare simulated concentrations of carbon monoxide in the atmosphere with measurements taken by MOPITT. The researchers were able to get further confirmation by analyzing data from aircraft-mounted instruments that were taking part in a field project over North America and Europe.

Pfister says the team is continuing to look at data taken last year at observing stations as far away as the Azores in order to track the movement of carbon monoxide and ozone from the wildfires. As a follow-up, she and other scientists plan to use a similar combination of observations, modeling, and numerical techniques to look at both natural and human-related emissions of carbon monoxide in South America.

The research was funded by a NASA grant in partnership with the National Science Foundation, which is the primary sponsor of NCAR.

Source: National Center for Atmospheric Research/University Corporation for Atmospheric Research

Explore further: Partial solar eclipse sweeps across North America

add to favorites email to friend print save as pdf

Related Stories

NASA, partners target megacities carbon emissions

Sep 24, 2014

Driving down busy Interstate 5 in Los Angeles in a nondescript blue Toyota Prius, Riley Duren of NASA's Jet Propulsion Laboratory, Pasadena, California, is a man on a mission as he surveys the vast urban ...

The origin of Uranus and Neptune elucidated?

Sep 24, 2014

A team of French-American researchers led by the UTINAM Institute (CNRS/Université de Franche-Comté) has just proposed a solution to the problematic chemical composition of Uranus and Neptune, thus providing ...

Recommended for you

China launches first mission to moon and back

1 hour ago

China launched its first space mission to the moon and back early Friday, authorities said, the latest step forward for Beijing's ambitious programme to one day land a Chinese citizen on the Earth's only ...

Close encounters: Comet siding spring seen next to mars

11 hours ago

(Phys.org) —This composite NASA Hubble Space Telescope Image captures the positions of comet Siding Spring and Mars in a never-before-seen close passage of a comet by the Red Planet, which happened at 2:28 ...

User comments : 0