“It’s another sign that the Arctic is unraveling. We had heat waves in the central Arctic last winter, record-low winter sea ice coverage, and even periods of ice retreat when it should be growing,” said Mark Serreze, director of the National Snow and Ice Data Center.
The Arctic’s record-warm winter has allowed thousands of square miles of sea ice off Alaska to melt more than a month early, leaving the shoreline vulnerable to waves and exposing dark ocean water to absorb more heat from the sun…As of May 24, the ice cover on the Chukchi Sea had melted away from the shore along a 300 mile stretch, from Point Hope all the way to Barrow, the northernmost town in the United States. Satellite and radar data show the ice-free area totaled about 54,000 square miles.
The huge area of open water off the coast is something you would normally see in early July, said Mark Serreze, director of the National Snow and Ice Data Center. The rapid disintegration of the Chukchi Sea ice is an “exclamation point” on a remarkable series of rapid fire Arctic changes, he said.
“It’s another sign that the Arctic is unraveling. We had heat waves in the central Arctic last winter, record-low winter sea ice coverage, and even periods of ice retreat when it should be growing. These extremes are moving from place to place,” Serreze said. The Arcticclimate change underway is caused by the buildup of heat-trapping greenhouse gases.
…The rapid recent decline in ice coverage and thickness has led researchers to believe that most of the Arctic Ocean will be free of ice in the summers as soon as the mid-2020s.
NSIDC researcher Julienne Stroeve, currently based at University College, London, said at a recent science conference that each of the last 10 years saw record-low sea ice coverage, and that there were seven months of record-low sea ice conditions during 2016, setting the stage for a Chukchi Sea meltdown.
Sea ice conditions were so unusual in late 2016 that NSIDC lead scientist Ted Scambos called it a black swan event in December, after reporting record low ice extent in the Arctic and Antarctica, far below natural historic variations. In mid-November 2016, much of the Arctic—spanning an area as large as the lower 48 states—was 30 to 35 degrees above average.
…a large part of the world’s coast is Arctic, and that erosion, on average, is taking a 1.5-foot bite out of that coastline each year, said Michael Fritz, a polar and ocean researcher with the Alfred Wegener Institute in Potsdam, Germany.
Evidence continues to mount that climate change has pushed the Arctic into a new state. Skyrocketing temperatures are altering the essence of the region, melting ice on land and sea, driving more intense wildfires, altering ocean circulation and dissolving permafrost.
A new report chronicles all these changes and warns that even if the world manages to keep global warming below the targeted 2°C threshold, some of the shifts could be permanent. Among the most harrowing are the disappearance of sea ice by the 2030s and more land ice melt than previously thought, pushing seas to more extreme heights.
This past winter is just the latest in a string of bizarre years and the report, authored by 90 Arctic experts, is the latest in a long line of increasingly dire warnings for the fastest-warming region on the planet. If carbon pollution isn’t slowed, parts of the Arctic could warm a whopping 16°F by the 2050s….
…The new analysis shows that the average number of days with sea ice cover has dropped by 10-20 days per decade since 1979….
The massive rush of freshwater into the Arctic Ocean is also reshaping ocean circulation and the ecology of the region. Researchers have seen a marked slowdown in North Atlantic circulation as cold, fresh water off Greenland’s southern tip has acted as a roadblock to the currents that steer water through the region. That has the potential to mess with ocean circulation as well as weather patterns, particularly in Europe.
The changes in the Arctic are a harbinger of what’s in store for the planet if we continue to emit carbon pollution. Some of these changes are likely irreversible. But the report does note that if the world sticks to its goal in the Paris Agreement, the region could reach an equilibrium that while different from its present state, is still less radical than the fate it faces if we keep going down the current carbon path.
Very heavy precipitation expected across Southern California on Friday and Northern California on Monday (including the Feather River watershed). NCEP
California is currently experiencing one of its wettest winters on record. Precipitation has been especially remarkable across the Northern Sierra watersheds, where liquid equivalent (rain+melted snow) is presently above 200% of average. Widespread flooding has already occurred across Northern California in recent weeks, and supersaturated soils are now leading to slope failures (mudslides and landslides) across much of the state. In additional to the “typical” flooding of regional rivers and streams that one might expect with prolonged heavy precipitation, California’s vast water storage and conveyance infrastructure is starting to crack under the strain–in some cases, quite literally….
Last month was easily the hottest November on record globally, according to satellite data sets.
…In fact, satellite data, ground-based weather stations, sea-based buoys, and even weather balloons all reveal a steady long-term warming trend. These satellites have documented a steady warming of the troposphere (the lower atmosphere). It always bears repeating that the satellites indirectly measure the temperature where we don’t live (the troposphere), so the data need a whole bunch of (easily screwed up) adjustments before it is useful to anyone. If you want a direct measure of the temperature at the surface where we actually live and grow food, you need NASA’s land and ocean temperature index (LOTI) from the Goddard Institute for Space Studies (GISS):
So, no matter how we look at it, we are warming rapidly. And carbon pollution is the primary cause. In fact, as I’ve written, the best estimate by climate scientists is that humans are responsible for all of the warming we have suffered since 1950…
Despite this, the denier-led House Science Committee tweeted out an erroneous Breitbart story last week about some satellites showing cooling. The story was quickly debunked by actual scientists here and everywhere.
Political people in the United States are watching the chaos in Washington in the moment. But some people in the science community are watching the chaos somewhere else — the Arctic. It’s polar night there now — the sun isn’t rising in much of the Arctic. That’s when the Arctic is supposed to get super-cold, when the sea ice that covers the vast Arctic Ocean is supposed to grow and thicken.
But in fall of 2016 — which has been a zany year for the region, with multiple records set for low levels of monthly sea ice — something is totally off. The Arctic is super-hot, even as a vast area of cold polar air has been displaced over Siberia.
At the same time, one of the key indicators of the state of the Arctic — the extent of sea ice covering the polar ocean — is at a record low. The ice is freezing up again, as it always does this time of year after reaching its September low, but it isn’t doing so as rapidly as usual.
In fact, the ice’s area is even lower than it was during the record-low 2012…
The hottest year on record globally in 2015 could be just another average year by 2025 if carbon emissions continue to rise at their current rate, according to new research…And no matter what action we take, human activities had already locked in a “new normal” for global average temperatures that would occur no later than 2040…
The results revealed that while global average temperatures would inevitably enter a new normal under all emissions scenarios, this wasn’t the case at seasonal and regional levels.
“It gives us hope to know that if we act quickly to reduce greenhouse gases, seasonal extremes might never enter a new normal state in the 21st Century at regional levels for the Southern Hemisphere summer and Northern Hemisphere winter,” Dr Lewis said….
Sophie C. Lewis, Andrew D. King, Sarah E. Perkins-Kirkpatrick. Defining a new normal for extremes in a warming world. Bulletin of the American Meteorological Society, 2016; DOI: 10.1175/BAMS-D-16-0183.1