Arctic report card 2017


The 2017 Arctic Report Card was released today (December 12, 2017) at the annual American Geophysical Union fall meeting in New Orleans. The NOAA-sponsored report, now in its 12th year, is a peer-reviewed report that brings together the work of 85 scientists from 12 nations.

According to the report, the warming trend transforming the Arctic persisted in 2017, resulting in the second warmest air temperatures, above average ocean temperatures, loss of sea ice, and a range of human, ocean and ecosystem effects.

While 2017 saw fewer records shattered than in 2016, the Arctic shows no sign of returning to the reliably frozen region it was decades ago, according to the report authors. Arctic temperatures continue to increase at double the rate of the global temperature increase.

See the 2017 Arctic Report Card here.

An iceberg floats in the Chukchi Sea in the Arctic Ocean. Image via NOAA.

The Arctic Report Card provides an annual update on how the region is faring environmentally, and compares these observations to the long-term record. One chapter in the Arctic Report Card uses historical data to show that the current observed rate of sea ice decline and warming temperatures are higher than at any other time in the last 1,500 years, and likely longer than that.

A NOAA statement listed major findings in this year’s report:

Warmer air temperature. Average annual air temperature over land was the second highest after 2016 in the observational record, with a temperature 2.9 degrees Fahrenheit (1.6 Celsius) above the average for 1981 to 2010.

Declining sea ice. This year’s maximum winter sea ice area, measured each March, was the lowest ever observed, while this year’s minimum area, measured each September, was eighth-lowest on record. Sea ice is also getting thinner each year, with year-old ice comprising 79 percent of coverage, and multi-year ice just 21 percent. In 1985, multi-year ice accounted for 45 percent of sea ice.

Above average ocean temperature. Sea surface temperatures in August 2017 were 7.2 degrees Fahrenheit (4 Celsius) above the average in the Barents and Chukchi seas. Surface waters of the Chukchi Sea have warmed 1.26 degrees Fahrenheit (0.7 Celsius) per decade since 1982.

Increasing Arctic ocean plankton blooms. Springtime melting and retreating sea ice which allows sunlight to reach the upper layers of the ocean, continues to stimulate increased chlorophyll as measured by satellite, which indicates more marine plant growth across the Arctic. This increase has occurred since measurements began in 2003.

Greener tundra. Overall vegetation, including plants getting bigger and leafier, and shrubs and trees taking over grassland or tundra, increased across the Arctic in 2015 and 2016, as measured by satellite. The greatest increases over the last three decades are occurring on the North Slope of Alaska, Canada’s tundra and Taimyr Peninsula of Siberia. The annual report on vegetation is based largely on data from sensors aboard NOAA weather satellites.

Snow cover up in Asia, down in North America. For the 11th year in the past 12, snow cover in the North American Arctic was below average, with communities experiencing earlier snow melt. The Eurasian part of the Arctic saw above average snow cover extent in 2017, the first time that’s happened since 2005.

Less melt on Greenland Ice Sheet. Melting began early on the Greenland Ice Sheet in 2017, but slowed during a cooler summer, resulting in below-average melting when compared to the previous nine years. Overall, the Greenland Ice Sheet, a major contributor to sea level rise, continued to lose mass this past year, as it has since 2002 when measurements began.

Icebergs, Ilulisat, Vestgronland, Greenland. Image via Greenland Travel/Flickr.

This year’s report card also includes special reports on how the warming trend is affecting valuable fisheries in the eastern Bering Sea; compromising roads, homes and infrastructure due to permafrost thaw; and threatening the high latitudes with increasingly frequent wildfires.

EarthSky’s 2018 lunar calendars are here! Get yours while they last.

Bottom line: The 2017 Arctic Report Card was released on December 12, says the Arctic saw the 2nd warmest year and the smallest winter sea ice coverage on record in 2017.

Read more from NOAA



from EarthSky http://ift.tt/2l5MZZZ

The 2017 Arctic Report Card was released today (December 12, 2017) at the annual American Geophysical Union fall meeting in New Orleans. The NOAA-sponsored report, now in its 12th year, is a peer-reviewed report that brings together the work of 85 scientists from 12 nations.

According to the report, the warming trend transforming the Arctic persisted in 2017, resulting in the second warmest air temperatures, above average ocean temperatures, loss of sea ice, and a range of human, ocean and ecosystem effects.

While 2017 saw fewer records shattered than in 2016, the Arctic shows no sign of returning to the reliably frozen region it was decades ago, according to the report authors. Arctic temperatures continue to increase at double the rate of the global temperature increase.

See the 2017 Arctic Report Card here.

An iceberg floats in the Chukchi Sea in the Arctic Ocean. Image via NOAA.

The Arctic Report Card provides an annual update on how the region is faring environmentally, and compares these observations to the long-term record. One chapter in the Arctic Report Card uses historical data to show that the current observed rate of sea ice decline and warming temperatures are higher than at any other time in the last 1,500 years, and likely longer than that.

A NOAA statement listed major findings in this year’s report:

Warmer air temperature. Average annual air temperature over land was the second highest after 2016 in the observational record, with a temperature 2.9 degrees Fahrenheit (1.6 Celsius) above the average for 1981 to 2010.

Declining sea ice. This year’s maximum winter sea ice area, measured each March, was the lowest ever observed, while this year’s minimum area, measured each September, was eighth-lowest on record. Sea ice is also getting thinner each year, with year-old ice comprising 79 percent of coverage, and multi-year ice just 21 percent. In 1985, multi-year ice accounted for 45 percent of sea ice.

Above average ocean temperature. Sea surface temperatures in August 2017 were 7.2 degrees Fahrenheit (4 Celsius) above the average in the Barents and Chukchi seas. Surface waters of the Chukchi Sea have warmed 1.26 degrees Fahrenheit (0.7 Celsius) per decade since 1982.

Increasing Arctic ocean plankton blooms. Springtime melting and retreating sea ice which allows sunlight to reach the upper layers of the ocean, continues to stimulate increased chlorophyll as measured by satellite, which indicates more marine plant growth across the Arctic. This increase has occurred since measurements began in 2003.

Greener tundra. Overall vegetation, including plants getting bigger and leafier, and shrubs and trees taking over grassland or tundra, increased across the Arctic in 2015 and 2016, as measured by satellite. The greatest increases over the last three decades are occurring on the North Slope of Alaska, Canada’s tundra and Taimyr Peninsula of Siberia. The annual report on vegetation is based largely on data from sensors aboard NOAA weather satellites.

Snow cover up in Asia, down in North America. For the 11th year in the past 12, snow cover in the North American Arctic was below average, with communities experiencing earlier snow melt. The Eurasian part of the Arctic saw above average snow cover extent in 2017, the first time that’s happened since 2005.

Less melt on Greenland Ice Sheet. Melting began early on the Greenland Ice Sheet in 2017, but slowed during a cooler summer, resulting in below-average melting when compared to the previous nine years. Overall, the Greenland Ice Sheet, a major contributor to sea level rise, continued to lose mass this past year, as it has since 2002 when measurements began.

Icebergs, Ilulisat, Vestgronland, Greenland. Image via Greenland Travel/Flickr.

This year’s report card also includes special reports on how the warming trend is affecting valuable fisheries in the eastern Bering Sea; compromising roads, homes and infrastructure due to permafrost thaw; and threatening the high latitudes with increasingly frequent wildfires.

EarthSky’s 2018 lunar calendars are here! Get yours while they last.

Bottom line: The 2017 Arctic Report Card was released on December 12, says the Arctic saw the 2nd warmest year and the smallest winter sea ice coverage on record in 2017.

Read more from NOAA



from EarthSky http://ift.tt/2l5MZZZ

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