NOAA released its 2018 Arctic Report Card on December 11. This year’s report shows – once again – how the climate of Earth’s north polar region is changing. Measurements include warmer air and ocean temperatures and declines in sea-ice that are driving shifts in animal habitats.
The annual Arctic Report Card – now in its 13th year – is a peer-reviewed report that provides an update on the region and compares these observations to the long-term record. The 2018 report was compiled from the research of 81 scientists working for governments and academia in 12 nations.
This year’s report shows that the Arctic region experienced the second-warmest air temperatures ever recorded; the second-lowest overall sea-ice coverage; lowest recorded winter ice in the Bering Sea; and earlier plankton blooms due to early melting of sea ice in the Bering Sea.
NASA’s Operation Icebridge captured this image of the town of Narsaq in Greenland in April 2018. Image via NOAA.
Here are some highlights from the report:
– Surface air temperatures in the Arctic continued to warm at twice the rate relative to the rest of the globe. Arctic air temperatures for the past five years (2014-18) have exceeded all previous records since 1900.
– Atmospheric warming continued to drive broad, long-term trends in declining terrestrial snow cover on land, melting of the Greenland Ice Sheet and lake ice, increasing summertime Arctic river discharge, and the expansion and greening of Arctic tundra vegetation.
– Despite increase of vegetation available for grazing, herd populations of caribou and wild reindeer across the Arctic tundra have declined by nearly 50 percent over the last two decades.
– In 2018, Arctic sea ice remained younger and thinner, and covered less area than in the past. The 12 lowest extents in the satellite record have occurred in the last 12 years.
– Warming Arctic Ocean conditions are also coinciding with an expansion of harmful toxic algal blooms in the Arctic Ocean, threatening food sources.
– Microplastic contamination is on the rise in the Arctic, posing a threat to seabirds and marine life that can ingest debris.
Declining Arctic sea ice: The 2018 Arctic Report Card found the Arctic region had the second-lowest overall sea-ice coverage on record. The map shows the age of sea ice in the Arctic ice pack in March 1985 (left) and March 2018 (right). Ice that is less than a year old is darkest blue. Ice that has survived at least 4 full years is white. Image via NOAA/Mark Tschudi./University of Colorado/CCAR.
The Report Card is intended for a wide audience, including scientists, teachers, students, decision-makers and the general public interested in the Arctic environment and science. You can read the 2018 Arctic Report Card here.
In addition to annual updates on ocean temperature, snow cover, tundra greenness and melting on the Greenland Ice Sheet, the report card also includes reports on multi-year environmental changes, including a long-term population decline of the region’s iconic wildlife species, the caribou. Other multi-year essays focused on the expansion northward of toxic harmful algae and significant concentrations of microplastic pollution that are transported by ocean currents into the Arctic Ocean from other parts of the global ocean.
Caribou and wild reindeer numbers drop 56 percent in 20 years: Arctic caribou and wild reindeer populations dropped sharply from 4.7 million to 2.1 million grazing animals in two decades, with the largest declines in Alaska and Canada. Scientists attribute the declines to Arctic warming, which is increasing the frequency of drought, affecting the quality of forage. Longer, warmer summers also increase flies, parasites and disease outbreaks in the herds. These caribou were spotted in Alaska’s Denali National Park and Preserve. Image via Rick Thoman/University of Alaska-Fairbanks.
Bottom line: NOAA released its 2018 Arctic Report Card.
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NOAA released its 2018 Arctic Report Card on December 11. This year’s report shows – once again – how the climate of Earth’s north polar region is changing. Measurements include warmer air and ocean temperatures and declines in sea-ice that are driving shifts in animal habitats.
The annual Arctic Report Card – now in its 13th year – is a peer-reviewed report that provides an update on the region and compares these observations to the long-term record. The 2018 report was compiled from the research of 81 scientists working for governments and academia in 12 nations.
This year’s report shows that the Arctic region experienced the second-warmest air temperatures ever recorded; the second-lowest overall sea-ice coverage; lowest recorded winter ice in the Bering Sea; and earlier plankton blooms due to early melting of sea ice in the Bering Sea.
NASA’s Operation Icebridge captured this image of the town of Narsaq in Greenland in April 2018. Image via NOAA.
Here are some highlights from the report:
– Surface air temperatures in the Arctic continued to warm at twice the rate relative to the rest of the globe. Arctic air temperatures for the past five years (2014-18) have exceeded all previous records since 1900.
– Atmospheric warming continued to drive broad, long-term trends in declining terrestrial snow cover on land, melting of the Greenland Ice Sheet and lake ice, increasing summertime Arctic river discharge, and the expansion and greening of Arctic tundra vegetation.
– Despite increase of vegetation available for grazing, herd populations of caribou and wild reindeer across the Arctic tundra have declined by nearly 50 percent over the last two decades.
– In 2018, Arctic sea ice remained younger and thinner, and covered less area than in the past. The 12 lowest extents in the satellite record have occurred in the last 12 years.
– Warming Arctic Ocean conditions are also coinciding with an expansion of harmful toxic algal blooms in the Arctic Ocean, threatening food sources.
– Microplastic contamination is on the rise in the Arctic, posing a threat to seabirds and marine life that can ingest debris.
Declining Arctic sea ice: The 2018 Arctic Report Card found the Arctic region had the second-lowest overall sea-ice coverage on record. The map shows the age of sea ice in the Arctic ice pack in March 1985 (left) and March 2018 (right). Ice that is less than a year old is darkest blue. Ice that has survived at least 4 full years is white. Image via NOAA/Mark Tschudi./University of Colorado/CCAR.
The Report Card is intended for a wide audience, including scientists, teachers, students, decision-makers and the general public interested in the Arctic environment and science. You can read the 2018 Arctic Report Card here.
In addition to annual updates on ocean temperature, snow cover, tundra greenness and melting on the Greenland Ice Sheet, the report card also includes reports on multi-year environmental changes, including a long-term population decline of the region’s iconic wildlife species, the caribou. Other multi-year essays focused on the expansion northward of toxic harmful algae and significant concentrations of microplastic pollution that are transported by ocean currents into the Arctic Ocean from other parts of the global ocean.
Caribou and wild reindeer numbers drop 56 percent in 20 years: Arctic caribou and wild reindeer populations dropped sharply from 4.7 million to 2.1 million grazing animals in two decades, with the largest declines in Alaska and Canada. Scientists attribute the declines to Arctic warming, which is increasing the frequency of drought, affecting the quality of forage. Longer, warmer summers also increase flies, parasites and disease outbreaks in the herds. These caribou were spotted in Alaska’s Denali National Park and Preserve. Image via Rick Thoman/University of Alaska-Fairbanks.
Bottom line: NOAA released its 2018 Arctic Report Card.
EarthSky lunar calendars are cool! They make great gifts. Order now. Going fast!
Want to see 2018’s brightest comet? How to see comet 46P/Wirtanen
from EarthSky https://ift.tt/2R3Hn0U
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