AP - Ozone levels over the Earth's far north dipped sharply early last year when polar winds trapped nitrogen pollutants, researchers reported Tuesday.{br}{br}View the Entire Article (http://us.rd.yahoo.com/dailynews/rss/science/*http://story.news.yahoo.com/news?tmpl=story2&u=/ap/20050301/ap_on_sc/arctic_ozone){br}