PLEA Network

15 December 2015, YALE Climate Connections, More Glum News on Arctic Warming.  Arctic’s trailing climate indicators are seen as the leading indicators for climate elsewhere on Earth. News from the Arctic hasn’t gotten any better in the 10 years since NOAA began producing an annual Arctic Report Card, and this year’s collection of results and essays is no exception. NOAA released its latest report December 15 at the meeting of the American Geophysical Union in San Francisco. “The Arctic is warming twice as fast as other parts of the planet,” said Rick Spinrad, NOAA chief scientist, adding “what happens in the Arctic doesn’t stay in the Arctic.” The average Arctic temperature change, 2.3 degrees F (1.3 degrees C) above average, continues to outpace change in the rest of the world, a phenomenon known as “Arctic amplification.” Since the beginning of the 20th century, Arctic warming is now a hefty 5.4 degrees F (3.0 degrees C), leading to significant changes to the region. “One could argue that the trailing indicators in the Arctic are the leading indicators for the rest of the climate,” Spinrad said. Two items from the report, which was written by 72 authors from 11 different countries, were highlighted here: a mysterious browning of Arctic tundra, and the impact of change on walruses. “Greenness” – a measure of photosynthetic activity by satellites — has been declining since 2001 (see Figure below), with a sharp drop-off in the past two to four years, running counter to the notion that more carbon dioxide is unequivocally good for plant life. “We don’t have an answer yet” to the declining greenness, said Howard Epstein, a scientist from the University of Virginia. “A drop in greenness for any given year isn’t alarming, or even two years in a row.” But four years makes for a noticeable trend. Read more here