Green summer tundra and the rolling Mulgrave Hills in northwestern Alaska's Cape Krusenstern National Monument are seen on July 11, 2011. The Mulgrave Hills are the farthest west extension of the ...

WASHINGTON—The icy region at the top of the globe, lashed by wildfire and pelted with increasingly heavy precipitation, has tipped into “uncharted territory,” scientists reported Tuesday. The Arctic ...

Arctic tundra, which has stored carbon for thousands of years, has now become a source of planet-warming pollution. As wildfires increase and hotter temperatures melt long-frozen ground, the region is ...

Arctic tundra is releasing greenhouse gases into the atmosphere as hotter temperatures melt frozen ground and wildfires increase. Arctic tundra, which has stored carbon for thousands of years, has now ...