We’re witnessing the fastest decline in Arctic sea ice in at least 1,500 years

We’re witnessing the fastest decline in Arctic sea ice in at least 1,500 years

SOURCE: Vox and Inside Climate News DATE: February 17, 2018 SNIP: Vox: The Arctic Ocean once froze reliably every year. Those days are over. Arctic sea ice extent has been measured by satellites since the 1970s. And scientists can sample ice cores, permafrost records, and tree rings to make some assumptions about the sea ice extent going back 1,500 years. And when you put that all on a chart, well, it looks a little scary. “The Arctic is going through the most unprecedented transition in human history,” Jeremy Mathis, director of NOAA’s Arctic research program, said at a press conference. “This year’s observations confirm that the Arctic shows no signs of returning to the reliably frozen state it was in just a decade ago.” The report, which you can read in full here, compiles trends that scientists have been seeing for years. The Arctic is warming at twice the rate of the rest of the world. And 2017 saw a new record low for the maximum sea ice extent (i.e., how much of the Arctic ocean freezes in the coldest depths of winter). That huge drop-off at the end? That’s “the largest magnitude decline in sea ice, and the greatest sustained rate in sea ice decline in that 1,500-year record,” said Emily Osborne, the NOAA scientist who compiled the data for the chart. Inside Climate News: In just eight days in mid-February, nearly a third of the sea ice covering the Bering Sea off Alaska’s west coast disappeared. That kind of ice loss and the changing climate as the planet warms is affecting the lives of the people who...
Sea ice tracking low in both hemispheres

Sea ice tracking low in both hemispheres

SOURCE: National Snow and Ice Data Center (NSIDC) DATE: February 6, 2018 SNIP: January of 2018 began and ended with satellite-era record lows in Arctic sea ice extent, resulting in a new record low for the month. Combined with low ice extent in the Antarctic, global sea ice extent is also at a record low. The linear rate of decline for January is 47,700 square kilometers (18,400 square miles) per year, or 3.3 percent per...
Sea ice algae blooms in the dark

Sea ice algae blooms in the dark

SOURCE: AAAS EurekAlert DATE: February 6, 2018 SNIP: Researchers from Aarhus University have measured a new world record: Small ice algae on the underside of the Arctic sea ice live and grow at a light level corresponding to only 0.02% of the light at the surface of the ice. Algae are the primary component of the Arctic food web and produce food far earlier in the year than previously thought. The general view has been that ice algae do not obtain sufficient light for growth when they are covered by a more than 30-50 cm deep cover of snow and ice. The new measurements completely change that view and show that ice algae may play an important role much earlier in the spring in the Arctic than hitherto assumed. Temperatures are rising in the Arctic. When the snow on top of the ice gets warmer, the algae residing on the underside of the ice receive more light. This may significantly impact the growth of the algae and the extent of the ‘spring bloom’. This new knowledge must be considered in the puzzle of how the Arctic will respond to a warmer...
Polar Bears Really Are Starving Because of Global Warming, Study Shows

Polar Bears Really Are Starving Because of Global Warming, Study Shows

SOURCE: National Geographic DATE: February 1, 2018 SNIP: Because of melting sea ice, it is likely that more polar bears will soon starve, warns a new study that discovered the large carnivores need to eat 60 percent more than anyone had realized. Turns out they are high-energy beasts, burning through 12,325 calories a day—despite sitting around most of the time, according to a unique metabolic analysis of wild bears published Thursday in Science. “Our study reveals polar bears’ utter dependence on seals,” said lead author Anthony Pagano, a wildlife biologist with the U.S. Geological Survey (USGS). If these results hold up, then it shows that the loss of sea ice may have a bigger impact on the bears than previously thought, said Amstrup, a former USGS polar bear expert. Amstrup’s own 2010 study projected that continued decline in sea ice would reduce the global population of bears by two thirds, to less than 10,000 by 2050. Climate change is heating up the Arctic faster than anywhere else, and sea ice is shrinking 14 percent per decade. Even today, in the middle of the bitter cold Arctic winter, satellites show there is about 770,000 square miles less sea ice than the 1981 to 2010 median (That’s an area larger than Alaska and California combined). In the late spring, the ice is breaking up sooner and forming later in the fall, forcing bears to burn huge amounts of energy walking or swimming long distances to get to any remaining ice. Or they stay on land longer, spending the summer and, increasingly, the fall fasting, living off their fat from the seals...
Alaska just had its warmest December on record

Alaska just had its warmest December on record

SOURCE: Anchorage Daily News DATE: January 9, 2018 SNIP: Last month was the warmest December on record in Alaska, according to a federal report released Monday. The statewide average temperature in December was 19.4 degrees, 15.7 degrees above the 20th century average, the National Oceanic and Atmospheric Administration’s report said. Records for Alaska go back to 1925. The report also found that 2017 was the third warmest year on record for the U.S. as a whole since record-keeping began in 1895. But December in Alaska specifically “was really quite remarkable,” said Rick Thoman, climate science and services manager for the National Weather Service. “Alaska, of course, being the only Arctic part of the U.S. … it’s often referred to as polar amplification, that climate is warming much more rapidly at high latitudes,” Thoman said. “We are the U.S.’s canary in that coal mine.” Last year was also the seventh warmest year in Alaska on record. The last four years are all in the top seven warmest on record. “There’s no comparable period like that,” said Thoman. “This is unique in our 93-year temperature...