Courtesy of Christopher Arp/USGS
Arctic warming signs
Climatologists pointing to the Arctic as the leading barometer of global change have plenty of new evidence that wholesale warming is under way. Observational data indicate that the region’s air, soils and water have warmed substantially since 2006, suggesting that the climate has established a “new normal” (SN Online: 12/2/11). Among the symptoms: An anomalous pool of freshwater (27 meters deep in places) fed by inland meltwater has been found floating atop Arctic Ocean seawater (SN Online: 4/5/11). Erosion is also up across the Arctic, with area coastlines retreating on average by a half-meter per year (SN: 5/21/11, p. 13).
This year’s summer sea ice extent, a comm