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La Niña Conditions Lead to a Dry and Cool Winter, Trapping Dust Pollution

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La Niña Conditions Lead to a Dry and Cool Winter, Trapping Dust Pollution

During the winter a brown cloud often hangs over the Valley and, according to a recent article in the Arizona Republic, this winter could be worse than usual. This is a La Niña year, meaning a cool, dry winter in Arizona with no wind and rain to clear the air, creating perfect conditions for trapping winter dust-pollution. Winter pollution is caused by both by fine particles (PM2.5) responsible for haze, and coarse dust (PM10) which accumulates in the upper respiratory tract of humans and is thus thought to contribute to chronic bronchitis, decreased lung function, coughing, painful breathing and premature death. Since 1996, Maricopa County has been classified as a serious PM10 nonattainment area. In 2007, Maricopa County submitted a plan to reduce PM10 pollution by 5% each year. Inability to meet this goal has led to a proposal for new off road vehicle restrictions as a further measure to decrease dust. Failure to reach EPA attainment can lead to the loss of federal transportation funds in addition to increased health threats for the citizens of Maricopa County.