Map shows trends in levels of artificial light at night (ALAN) across the Western Hemisphere from 1992 to 2013. Pink and red dots show increases; blue dots show where light levels are decreasing. Graphic by Frank La Sorte.
Map shows trends in levels of artificial light at night (ALAN) across the Western Hemisphere from 1992 to 2013. Pink and red dots show increases; blue dots show where light levels are decreasing. Graphic by Frank La Sorte.