Comparisons of today to prehistoric “paleo” climates reveal the Arctic is changing faster than at any time in at least 1,500 years, altering familiar weather patterns in distant southern latitudes, the U.S. National Oceanic and Atmospheric Administration (NOAA) reports in an annual assessment of the region.
The comparison with the distant past was a new element in the agency’s yearly look to the Far North. So was the assertion that the fast-warming Arctic is beginning to disturb weather in the lower 48 American states.
“We’re fairly confident now that the warming that’s occurring, the loss of sea ice that’s occurring, are creating conditions where more extreme weather events are beginning to show up in North America,” said Jeremy Mathis, director of NOAA’s Arctic Research Program, while presenting the agency’s Arctic Report Card to the 2017 meeting of the American Geophysical Union in New Orleans.
“These changes will have an impact on all of our lives,” Mathis said. “They will mean living with more extreme weather events, paying higher food prices, and dealing with the impacts of climate refugees.”
The section of the report comparing the present to the past found that the recent decline of Arctic sea ice is “outside the range of natural variability and unprecedented” in the last 1,450 years. Surface temperatures are rising faster than at any time in (at least) the last 2,000 years.
Otherwise, the Report Card largely echoed earlier ones in its litany of disturbing symptoms of a collapsing cryosphere. 2017 was the second-warmest year on record in the Arctic, after last year. The extent of sea ice at its maximum was at a new record low. Tundra is growing trees and bushes, permafrost is rapidly melting, and plankton are blooming in the Arctic ocean.
And the course of change appears irreversible, NOAA states. The Arctic “shows no sign of returning to reliably frozen region of recent past decades,” headlined the news release announcing the report’s release.
Rather “observations in 2017 continue to indicate that the Arctic environmental system has reached a ‘new normal’, characterized by long-term losses of sea ice, winter snow cover, and the mass of ice in the Greenland Ice Sheet, and warming sea and permafrost temperatures.”
Other research suggests this “new ‘normal” may also be short-lived, as irreversible warming and melting test no fewer than 19 potential climate “tipping points,” any one of which could lead to catastrophic climate impacts around the world.
The NOAA report was the second in recent weeks to catalogue empirical observations of climate instability that challenge the denialist orthodoxy of many in the top ranks of the current U.S. administration.
“The Report Card dispassionately documents an array of striking changes in the Arctic environment, which it attributes to increasing greenhouse gases in the atmosphere.” observed Phil Duffy, president of the Woods Hole Research Center. “Like the Climate Science Special Report released in November, [it] is completely at odds with the policies and statements of the Trump administration, which continues to question the reality of human-caused climate change.”