Global Warming

Arctic Is Heating Up Twice as Quickly as Rest of World

Bad news for polar bears: The Arctic is still warming at twice the pace of the rest of the planet, according to a new federal report.

Last year, air temperatures in the northernmost regions of the globe were, on average, 1.8 degrees Fahrenheit (1 degree Celsius) higher than normal. Unusually warm years like 2014 have only become more frequent in the Arctic in the past decade, even as the rate of temperature increase slowed for the rest of the world.

In 2014, the Greenland Ice Sheet's heat-deflecting brightness hit a low; spring snow cover dwindled to record lows in Eurasia; polar regions had a below-average extent of summer sea ice, and as for the polar bears that depend on that ice to survive, some populations have declined, according to the report.

The findings are included in the National Oceanic and Atmospheric Association's (NOAA) annual "Arctic Report Card," a comprehensive review of the North Pole's health that is assembled by more than 60 scientists.

The Arctic warms at a higher rate than lower latitudes because of a well-documented effect known as Arctic amplification of global warming, Richter-Menge told reporters. Arctic amplification is a self-feeding cycle. Because of their light colour, sea ice and snow bounces radiation from the sun back into the atmosphere. But when more ice and snow melts, more of the dark-coloured patches of earth and ocean are exposed, locking more heat into the already-warming planet's surface.

Rising temperatures in the Arctic are thought to affect the rest of the planet. Some research has suggested that warming around the North Pole can cause the typical path of the jet stream to go haywire, though scientists have yet to reach a consensus. Without data for a long period of time, it's difficult to tell whether this phenomenon is really a trend or part of the "normal chaos" of the atmosphere, said James Overland, an oceanographer with NOAA's Pacific Marine Environmental Laboratory. Regardless of the cause, a wavy jet stream can have a huge influence on weather, the report illustrates. For example, a twisted jet stream led to remarkable temperature spikes in Alaska in January, when the region experienced temperatures as much as 18 degrees F (10 degrees C) higher than normal.