Alaska and Canada Pollute Texas

Pollutants traveling even thousands of miles can impact air quality, scientists using NASA satellites and other data suggest.

The study concludes that ozone pollution levels increased significantly in the air above Houston on July 19 and 20, 2004. Researchers attribute this increase in part as a result of smoke transported into the area over the course of a week from forest fires raging in Alaska and Canada. The above image from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Aqua satellite shows forest fires (outlined in red) and thick smoke over Alaska and Canada on July 13, 2004.

They sampled a variety of trace gases and aerosols--tiny particles suspended in the air -across North America. During the time of the study, forest fires in western Canada and eastern Alaska were consuming more acres than at any time during the last 50 years. Meteorological conditions carried smoke from these intense fires eastward and southward to the U.S. Gulf Coast.

Such pollution episodes will continue. Therefore, understanding the transport and transformation of gases and aerosols over long distances is needed for improved understanding and air quality forecasting, scientists suggest.

This study is detailed in the September issue of the American Geophysical Union's Journal of Geophysical Research - Atmospheres.

--LiveScience Staff

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Credit: NASA/GSFC