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Accelerating Warming of the Arctic Ocean

Desember 23, 2016 Add Comment

Stronger Winds causing further Warming of the Arctic Ocean

Warming is accelerating in the Arctic. On December 22, 2016, the Arctic was on average 3.33°C or 5.99°F warmer than it was in 1979-2000.

Within the Arctic, the Arctic Ocean is warming most rapidly. The image below gives a snapshot of the situation on December 22, 2016 at 06:00 UTC. The Arctic as a whole was as much as 3.34°C or 6.01°F warmer than in 1979-2000. At the same time, temperatures over much of the Arctic Ocean were at the top end of the scale, i.e. as much as 30°C or 54°F warmer than in 1979-2000 (pink color at 90°N latitude).

The temperature in the Arctic (north of 80°N Latitude) is also illustrated by the image below. The red line of the temperature for 2016, up to December 22, 2016. The green line is the 1958-2002 temperature.

Over the entire year 2016, warming was most profound over the Arctic Ocean, which was more than 2.5°C or 4.5°F warmer than 1981-2010, as illustrated by the image below.

The animation below illustrates how this anomaly developed over the past few years, each time showing a 365-day period, starting in 2014 and each time shifted by roughly one month.

These high temperatures over the Arctic Ocean reflect warm water of the Arctic Ocean, with heat added from the Atlantic Ocean and the Pacific Ocean. The image below shows ocean warming, with temperatures rising particularly rapidly on the Northern Hemisphere.

[ Ocean warming, from earlier post ]

Warmer water of the Atlantic Ocean is pushed by the Coriolis force toward the Arctic Ocean. The huge amounts of energy entering the oceans translate not only into higher temperatures of the water and of the air over the water, but also into higher waves and stronger winds.

Above image shows winds on December 29, 2016.

[ click on images to enlarge ]

As above image shows, waves were as high as 7.65 m or 25.1 ft in between Norway and Svalbard on December 29, 2016.

Sea surface temperatures west of Svalbard were as high as 14.6°C (58.2°F) on December 29, 2016. Sea surface temperature went up at the end of December at this spot, while the longer-term average went down in line with the change in seasons.

Underneath the surface of the North Atlantic, the water is much warmer than at the surface, and this temperature difference increases as winds get stronger and cause stronger evaporation, which has a cooling effect on the sea surface. This is illustrated by the image below, showing both the North Pacific and the North Atlantic on November 28, 2016.

The fact that the North Pacific shows a huge cold area, while the cold area in the North Atlantic has virtually disappeared, suggests that the cold area in the North Pacific is not the result of melt-water. The path of the cold areas and the low temperatures over the continents at higher latitudes, give further indications that strong winds are causing such cold areas. The image below shows that a cold area reappearing in the North Atlantic as it gets hit by strong winds (see video further below).

Above images and the image below, from an earlier post, illustrate how stronger evaporation and the resulting precipitation, at times in combination with melt-water, could create cold freshwater lids on both the North Atlantic and the North Pacific. The situation in the North Atlantic is very dangerous, as such a lid can cause much more heat to get carried into the Arctic Ocean underneath the sea surface of the North Atlantic, due to reduced heat transfer to the atmosphere from water on its way to the Arctic Ocean.

The image below, from an earlier post, shows the depth of Barents Sea, which is relatively shallow around Svalbard.

As the image on the right shows, this spot warms up due to a sea current that brings warm water from the North Atlantic into the Arctic Ocean.

Above images give an indication of the temperature of the water in the Atlantic Ocean underneath the sea surface, as the water comes to the surface near Svalbard, as also illustrated by the plot on the right.

The Arctic Ocean is now warming underneath the sea ice due to the inflow of warm water from the Atlantic Ocean and the Pacific Ocean.

The Arctic Ocean is also warming due to feedbacks such as increased levels of water vapor in the atmosphere, warmer river water running into the Arctic Ocean and soot from wildfires that can settle on snow and ice, resulting in further albedo changes.

Further feedbacks of global warming include warmer air temperatures, higher waves and stronger winds that all speed up the demise of snow and ice.

Stronger winds are pushing warm water from the North Atlantic into the Arctic Ocean. Why are these winds getting stronger? As the Arctic warms faster than the rest of the world, the temperature difference between the Arctic and the Equator decreases, making the Jet Stream wavier, with longer loops extending to the north and to the south. At the same time, the temperature difference between the oceans and the continents (Europe, Asia and North America) is increasing, speeding up the Jet Stream as it travels, e.g., over the North Atlantic towards the Arctic Ocean.

[ click on images to enlarge ]

The above 14.6°C SST on December 29, 2016, near Svalbard is the result of warm water being pushed from the North Atlantic into the Arctic Ocean. The situation is illustrated by the above combination image that shows that the Jet stream is forecast to reach speeds as high as 319 km/h or 198 mph in between North America and Greenland on December 31, 2016 (left panel). At the same time, surface winds are forecasts to reach speeds as high as 95 km/h or 59 mph (center panel) and waves as high as 8.96 m or 29.4 ft in between Norway and Svalbard (right panel).

The situation is further illustrated by the video below, showing winds over the North Atlantic from December 27, 2016 to January 3, 2017, as forecasts by cci-reanalyzer.org.

The fact that this is not a one-off event is also illustrated by the image on the right, showing that the Jet Stream reached speeds of 384 km/h or 239 mph over the Pacific Ocean on December 27, 2015. At the same day and time in 2015, the Jet Stream reached speeds as high as 430 km/h or 267 mph as it moved over North America on its way over the North Atlantic.

In conclusion, increasingly stronger winds are causing huge amounts of heat to enter the Arctic Ocean from the North Atlantic, and also from the Pacific Ocean. As the water of the Arctic Ocean keeps warming, the danger increases that methane hydrates at the bottom of the Arctic Ocean will destabilize.

The danger is illustrated by the two images above and below, recorded by the MetOp2 satellite on the afternoon of Christmas eve and Christmas.

Continued warming could trigger huge abrupt methane eruptions leading to mass destruction and extinction.

Potential warming by more than 10°C or 18°F by 2026 (from: Climate Plan Summary, see also: the extinction page)

The image below shows the associated temperature rise from preindustrial to 2026, with figures discussed in more detail on the Temperature page.

The situation is dire and calls for comprehensive and effective action as described at the Climate Plan.

Two videos complement this. Have a look at the video entitled Abrupt Climate Disrupting Arctic Changes: Part 2 of 2 by Paul Beckwith, in particular the segment from 8:30 to 12:00 minutes where Paul discusses how wind patterns are changing over the Arctic.

For further thoughts on the situation, also have a look at the video below in which Jennifer Hynes interviews Peter Wadhams.

Arctic Sea Ice Collapse Threatens

albedo Arctic heat melting methane ocean sea ice sea surface temperature soot thickness wildfires

Juli 10, 2015 Add Comment

The image below compares the Arctic sea ice thickness on July 14, 2012 (left panel) and on July 14, 2015 (right panel), using Naval Research Laboratory images.

The Naval Research Laboratory's 30-day animation below shows how this situation developed, ending with a forecast for July 17, 2015, run on July 9, 2015.

The dramatic decline of the sea ice, especially north of North America, is the result of a combination of factors, including:

very high levels of greenhouse gases over the Arctic Ocean
very high levels of ocean heat
heatwaves over North America and Siberia extending high air temperatures over the Arctic Ocean
wildfires triggered by these heatwaves resulting in darkening compounds settling on snow and ice
very warm river water running into the Arctic Ocean, as illustrated by the image below.

With still two months of melting to go before the sea ice can be expected to reach its minimum for 2015, the threat of sea ice collapse is ominous. The Arctic-News Blog has been warning for years about the growing chance of a collapse of the sea ice, in which case huge amounts of sunlight that previously were reflected back into space, as well as heat that previously went into melting the ice, will then instead have to be absorbed by the water, resulting in a dramatic rise of sea surface temperatures.

The image below shows the already very high sea surface temperature anomalies as at July 10, 2015.

More open water will then come with an increased chance of storms that can cause high sea surface temperatures to be mixed down all the way to seafloor of the Arctic Ocean, which in many cases is less than 50 m (164 ft) deep.

Meanwhile, ocean heat is accumulating off the coast of North America, as illustrated by the image below showing sea surface temperature as high as 31.8°C (89.24°F) on July 8-9, 2015.

Massive amounts of ocean heat will be carried by the Gulf Stream into the Arctic Ocean over the next few months. The combined result of high sea surface temperatures being mixed down to the seafloor and the ocean heat entering the Arctic Ocean from the Atlantic and Pacific Oceans can be expected to result in dramatic methane eruptions from the Arctic Ocean seafloor by October 2015.

Currently, methane levels are high, especially north of Greenland, as illustrated by the image below showing that on July 10, 2015 (am), levels as high as 2416 parts per billion were recorded at 6,041 m (19,820 ft) altitude, while mean methane levels also reached 1831 parts per billion at this altitude.

The situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan.

ARCTIC SEA ICE COLLAPSE THREATENSThis image compares the Arctic sea ice thickness on July 14, 2012 (left panel) and on...
Posted by Sam Carana on Friday, July 10, 2015

Arctic Methane Skyrocketing

anomaly Arctic climate methane Paul Beckwith sea surface temperature SST temperature

Mei 31, 2015 Add Comment

The map below shows observatories in the Arctic.

'Arctic methane skyrocketing' is the title of a video by Paul Beckwith discussing recent rises in methane levels in the Arctic.

Paul's description: "I discuss how ground level flask measurements of methane have been spiking upwards over the last few years. I analyze the implications to the breakdown of climate stability, causing jet stream fracturing and weather regime change. I believe that this behaviour will rapidly worsen as Arctic temperature amplification continues, leading our planet to a much warmer and unrecognizable climate over the next 5 to 10 years."

Below are some NOAA images showing methane levels (surface flasks) recorded at Arctic observatories.

Below is an image showing hourly average in situ measurements at Barrow, Alaska, including one very high reading, from an earlier post.

The image below shows sea surface temperature anomalies in the Arctic on May 30, 2015.

The situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan page.

Sea surface temperature anomalies in the Arctic on May 30, 2015. From the post: 'Arctic Methane Skyrocketing' http://arctic-news.blogspot.com/2015/05/arctic-methane-skyrocketing.html
Posted by Sam Carana on Sunday, May 31, 2015

Mackenzie River Warming

Arctic heat Mackenzie River ocean sea ice sea surface temperature warming

Mei 15, 2015 Add Comment

On May 12, 2015, a temperature of 80.1°F (or 26.7°C) was recorded in the north of Canada, at a location just north of latitude 63°N.

High temperatures in such locations are very worrying, for a number of reasons, including:

They are examples of heatwaves that can increasingly extend far to the north, all the way into the Arctic Ocean, speeding up warming of the Arctic Ocean seabed and threatening to unleash huge methane eruptions.
They set the scene for wildfires that emit not only greenhouse gases such as carbon dioxide and methane, but also pollutants such as carbon monoxide (that depletes hydroxyl that could otherwise break down methane) and black carbon (that when settling on ice causes it to absorb more sunlight).
They cause warming of the water of rivers that end up in the Arctic Ocean, thus resulting in additional sea ice decline and warming of the Arctic Ocean seabed.

The image below shows increased sea surface temperature anomalies in the area of the Beaufort Sea where the Mackenzie River is flowing into the Arctic Ocean.

The image below further illustrates the situation, with sea ice thickness (in m) down to zero where the Mackenzie River flows into the Arctic Ocean.

Things look set to get worse. The forecast for May 16, 2015, shows high temperatures extending all the way to the coast where the Mackenzie River flows into the Arctic Ocean.

Updates follow below:
Alaska is hit by high temperatures as well. The image below shows temperatures as high as 25.3°C (77.54°F) at a location just north of latitude 66°N in Alaska.

Below a forecast for May 23, 2015, showing temperatures in Alaska and neighboring parts of Canada that are 36°F (20°C) higher than they used to be (1979-2000 baseline).

The image below shows that temperatures as high as 30.2°C (86.36°F) are forecast for Alaska for May 23, 2015, along the path of the Yukon River, at a latitude of ~66 degrees North (65.98°N).

Furthermore, temperatures as high as 24.2°C (75.56°F) are forecast for the coast, close to where the Mackenzie River flows into the Arctic Ocean. Off the coast, over the water of the Arctic Ocean, temperatures as high as 8°C (46.4°F) are forecast, for a location just north of latitude 70°N, while temperatures as high as 15°C (59°F) are forecast for a location over the water of the Arctic Ocean closer to land.

As the image below illustrates, the jet stream is forecast to move across Alaska on May 23, 2015, bringing warm air into the atmosphere over the Arctic Ocean. The image gives the jet stream's speed at three locations, i.e. the jet stream is forecast to reach speeds as high as 262 km/h (162.8 mph, bottom green circle) over the Pacific Ocean, 165 km/h (102.5 mph, middle green circle) south of Alaska, and 172 km/h (106.9 mph, top green circle) over the Arctic Ocean.

Looking at salinity is a way to see the impact of rivers. The animation below, created with Naval Research Laboratory images over the period May 16 to 20, 2015 (run on May 18, 2015), shows salinity levels falling where the Mackenzie River flows into the Arctic Ocean.

Salinity works in several ways. Falling salinity will increase the temperature at which the sea ice melts. However, such an increase can only temporarily hold back melting, as illustrated by the combination image below, comparing sea ice thickness between May 7 and May 18, 2015.

Let's have a look at some of the feedbacks that haven't been discussed much in earlier posts. The potential for rivers to contribute to sea ice decline is depicted in the diagram below (feedback #24), i.e. extreme weather causing warming of rivers that flow into the Arctic Ocean. Furthermore, evaporation rates are higher over fresh water surfaces than over saline water surfaces (feedback #26) and the resulting increase in water vapor and clouds contributes to further warming (feedback #25), while rain falling on the sea ice will also cause its albedo to decline. The latter feedback also closes some loops. in that sea ice retreat results in more open water, in turn resulting in more water vapor and clouds.

Another feedback is that, as more sea ice turns into open water, less infrared radiation will be emitted and sent out into space, since open oceans are less efficient than sea ice when it comes to emitting in the far-infrared region of the spectrum (feedback #23). Furthermore, as sea ice declines, the increase in Arctic phytoplankton warms the ocean surface layer through direct biological heating (feedback #22).

For more discussion of these feedbacks, see the feedbacks page. In conclusion, the situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan page.

Forecast for May 16, 2015, showing high temperatures extending all the way to the coast where the Mackenzie River flows...
Posted by Sam Carana on Friday, May 15, 2015