Atmospheric carbon dioxide content for March 4 2017 -- 407.46 parts per million
One year ago -- 403.79 ppm
February 2017 -- average 406.42 ppm
February 2016 -- 404.04 ppm
January 2017 was warmest January since 1893
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jim williams
Special report: Go behind Minnesota's pro-athlete curtain to see how the best athletes in our state get ready for their biggest moment: gameday.