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June 3 - 6, 2011
The smoke that is clouding skies in much of the Midwest contains a mix of gases and fine particles. One of the gases released when a fire burns is carbon monoxide, a colorless, odorless gas that damages human health by limiting the flow of oxygen through the body. It is also a key ingredient in the production of harmful ground-level ozone and urban haze.
This series of images shows high concentrations of carbon monoxide moving across the United States from the Wallow Fire in eastern Arizona between June 3 and June 6, 2011. The images were made from data from the Atmospheric Infrared Sounder (AIRS) on the Aqua satellite. High concentrations of carbon monoxide are shown in red. Pale gray areas are places where the sensor did not collect data.
On June 3, carbon monoxide flows northeast directly from eastern Arizona. By the next day, concentrations are higher north of the fire. A natural color satellite image showed dense smoke over Colorado that day. Over the following two days, pulses of carbon monoxide drifted east. Carbon monoxide in Canada may be from wildfires in Alberta.
While much of the carbon monoxide shown here is from the Wallow Fire, some may also be from urban pollution. In the United States, vehicles and other gasoline-powered equipment generate the bulk of carbon monoxide pollution.
NASA Earth Observatory image created by Jesse Allen, using data provided by the AIRS science team at NASA/JPL. Caption by Holli Riebeek.