Accelerated Warming in the Arctic

Warming in the Arctic is accelerating. On June 25, 2015, high temperatures hit North America. Temperatures as high as 30.3°C (86.54°F) were recorded where the Mackenzie River is flowing into the Arctic Ocean.

June 25, 2015 - High temperatures over North America, close to the Arctic Ocean

On July 1, 2015, temperatures are forecast to be as high as 111.4°F (or 44.1°C) near Chico, north of San Francisco. Temperatures are forecast to be high over most of North America and Eastern Siberia, threatening to further warm up waters of the Arctic Ocean.

Forecast for July 1, 2015 - High temperatures over North America, close to the Arctic Ocean

The image below shows that on June 27, 2015, temperatures of well over 40°C (104°F) were recorded in Europe and in Pakistan, where temperatures earlier this month had reached 49°C (120.2°F) in some places. The heat wave reportedly killed 1233 people in Karachi alone. This in addition to the 2500 people killed earlier in India by high temperatures.

June 27, 2015 - High temperatures over Russia, close to the Arctic Ocean

High temperatures at 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. 

June 24, 2015 - Smoke from wildfires in Alaska - from: wunderground.com

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

Very warm water is also flowing from the Pacific Ocean through the Bering Strait into the Arctic Ocean.  As the image below shows, the water that is flowing into the Arctic Ocean from the Pacific is much warmer than it used to be, as much as 6.1°C (10.98°F) warmer.

View the flow of the water on the animated version of above image at earth.nullschool.net

As said above, warm water flowing from rivers into the Arctic Ocean is a major contributor to these sea surface temperature anomalies. As also illustrated by the NOAA image below, rivers carrying warm water into the Bering Strait include the Kobuk River, the Naotak River and the Yukon River that flows all the way from British Columbia, Canada, through Alaska and ends in the Bering Strait. Sea surface temperatures near the coast of Alaska were as high as 19°C (66.2°F) from June 21-24, 2015.

Sea surface temperatures near the coast of Alaska as high as 19°C (66.2°F) from June 21-24, 2015

The Naval Research Laboratory animation below shows changes to Arctic sea ice thickness. Sea ice thickness (in m) down to zero where the Mackenzie River flows into the Arctic Ocean and in the Bering Strait where warm water from the Pacific is entering the Arctic Ocean.

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


Related

- Gulf Stream brings ever warmer water into Arctic Ocean
http://arctic-news.blogspot.com/2015/06/gulf-stream-brings-ever-warmer-water-into-arctic-ocean.html

- High Temperatures in the Arctic

http://arctic-news.blogspot.com/2015/06/high-temperatures-in-the-arctic.html

- Heat Wave Forecast For Russia Early June 2015http://arctic-news.blogspot.com/2015/06/heat-wave-forecast-for-russia-early-june-2015.html

Sea surface temperature anomalies in the Arctic. Note the warming in the area of the Beaufort Sea where the Mackenzie...
Posted by Sam Carana on Thursday, June 25, 2015

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Mackenzie River Warming

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

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River ice reveals new twist on Arctic melt

A new study led by Lance Lesack, a Simon Fraser University geographer and Faculty of Environment professor, has discovered unexpected climate-driven changes in the mighty Mackenzie River’s ice breakup. This discovery may help resolve the complex puzzle underlying why Arctic ice is disappearing more rapidly than expected.

Lance Lesack,
photo by Simon Fraser University

Lesack is the lead author on Local spring warming drives earlier river-ice breakup in a large Arctic delta. Published recently in Geophysical Research Letters, the study has co-authors at Wilfrid Laurier University, the University of Alberta and Memorial University.

Its goal was to understand how warming global temperatures and the intensifying Arctic hydrological cycle associated with them may be driving increasing water discharges and more rapid ice breakup in the Arctic’s great rivers.

But the researchers stumbled upon an unexpected phenomenon while trying to figure out why the Mackenzie River’s annual ice breakup has been shortening even though its water discharge isn’t increasing, as in Russian rivers.

Just slightly warmer springs with unexpected snowfall declines — rather than warmer winters or increasing river discharge, as previously suspected — can drive earlier-than-expected ice breakup in great Arctic rivers.

The Mackenzie exemplifies this unexpected phenomenon. The researchers discovered this by accessing records dating back to 1958 of the river’s water levels, snow depths, air temperatures and times of ice breakup.

This finding is significant, as Arctic snow and ice systems are important climate-system components that affect the Earth’s ability to reflect solar radiation.

Mackenzie delta river, before (top) and after
(bottom, one day later) onset of dynamic ice
breakup in the central Mackenzie's delta middle
channel. Photos by Simon Fraser University.

“Our surprising finding was that spring temperatures, the period when river-ice melt occurs, had warmed by only 3.2 degrees Celsius. Yet this small change was responsible for more than 80 per cent of the variation in the earlier ice breakups, whereas winter temperatures had warmed by 5.3 degrees but explained little of this variation,” says Lesack.

“This is a strong response in ice breakup for a relatively modest degree of warming, but further investigation showed that by winter’s end snow depths had also declined by one third over this period. The lesser snow depths mean less solar energy is needed to drive ice breakup.”

Lesack says this is the first field-based study to uncover an important effect of reduced winter snowfall and warmer springs in the Arctic — earlier-than-expected, climate-change-related ice breakup.

“The polar regions have a disproportionate effect on planetary reflectivity because so much of these regions consist of ice and snow,” says Lesack. “Most of the planetary sea ice is in the Arctic and the Arctic landmass is also seasonally covered by extensive snow. If such ice and snow change significantly, this will affect the global climate system and would be something to worry about.”

Lesack hopes this study’s findings motivate Canadian government agencies to reconsider their moves towards reducing or eliminating ground-based monitoring programs that measure important environmental variables.

There are few long-term, ground-based snow depth records from the Arctic. This study’s findings were based on such records at Inuvik dating back to 1958. They significantly pre-dated remote sensing records that extend back only to 1980. Without this longer view into the past, this study’s co-authors would still be in the dark about the more rapid than expected Arctic melt and planetary heat-up happening.



Backgrounder:

Quotes by Lance Lesack

• “Our work suggests that the effects of reduced winter snowfall should be further investigated in other aspects of the changing Arctic, such as the surprisingly rapid reduction in sea-ice cover and the unexpected collapses of several Canadian ice shelves.” 
• “Our findings should also be of interest to people and industries that exist in the Arctic, where changes in the growth and decay of rivers, lakes or sea-ice may affect their daily lives. Ice roads and shipping over them depend on knowing when the ice roads can be travelled upon or when ferry crossings can be operated during open water.”

Facts:

• Canada’s Mackenzie and several Russian rivers are among the Arctic’s gigantic waterways. The hydrological cycle is the cycling of water from the oceans to the atmosphere and back down to the continents, which the rivers then drain back to the ocean. Planetary warming hastens this cycle, which should lead to higher river discharge, more rapid river ice breakup, and ultimately more extreme weather patterns. 
• About a third of the size of Switzerland and reaching 200 kilometres inland, the Mackenzie River delta sits at the end of Canada’s longest river and sustains 45,000 lakes. 
• The Mackenzie River delta and other Arctic deltas are considered biological hotspots because their sites have much higher biological productivity and biodiversity than their surrounding Arctic environment. Their peak river levels enhance marine ecosystems by flushing nutrients and organic matter from vast deltas that sit at freshwater-ocean water interfaces into the ocean. 
• In 2007 SFU geographer Lance Lesack co-authored a study that found rising water levels in the Mackenzie River delta, induced by climate-related sea-level rise, were three times higher than predicted. The authors worried that the faster-than-expected changes could have important impacts on the region’s human and animal life, and industry.

Press release by Simon Fraser University

http://www.sfu.ca/pamr/media-releases/2014/river-ice-reveals-new-twist-on-arctic-melt.html

Local spring warming drives earlier river-ice breakup in a large Arctic delta
Lance F. W. Lesack, Philip Marsh, Faye E. Hicks and Donald L. Forbes

http://onlinelibrary.wiley.com/doi/10.1002/2013GL058761/abstract

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