Last year, the Arctic was some 3.5°C warmer than it was at the start of the Industrial Revolution. Was this 3.5°C a spike or was it part of a trend pointing at even higher temperature anomalies this year and the following years?

Above image shows NASA annual mean 64°N-90°N land-ocean temperature anomalies from 1951-1980, with +0.59°C added for the rise from 1750 to 1951-1980. A polynomial trend is added (based on 1880-2016 data), pointing at 4.5°C anomaly by 2019.

Will the Arctic keep warming over the coming years in line with this trend? Let's have a look at what affects temperatures in the Arctic most, specifically Ocean Heat, Sea Ice, Land Temperatures and Emissions.

1. Ocean Heat

Warmer Oceans on the Northern Hemisphere will contribute strongly to warming in the Arctic. Here's a graph showing a trend pointing at continued warming of the oceans on the Northern Hemisphere.

Will oceans keep warming like that, in particular the North Atlantic? The Coriolis force keeps pushing warm water of the North Atlantic along the Gulf Stream toward the Arctic Ocean.

On the image on the right, the Gulf Stream shows up as the warmer water (orange and yellow) off the coast of North America.

Thus, as oceans keep warming, warmer water will reach the Arctic Ocean, melting the sea ice from below.

The image on the right shows that the sea surface was 9.3°C or 16.8°F warmer than 1981-2011 on May 7, 2017, at the location marked by the green circle.

2. Sea ice

Meanwhile, the sun will warm up the sea ice from above. The sea ice acts as a barrier, insulating the water of the Arctic Ocean from the heat from above. As long as there is sea ice, water just underneath the sea ice will stay close to freezing point.

Sea ice can strongly affect the amount of heat that is retained by Earth. Sea ice reflects most sunlight back into space, but in the absence of sea ice, most sunlight will instead be absorbed by oceans.

For almost a year now, global sea ice extent has been way below what it used to be, meaning that huge amounts of sunlight that were previously reflected back into space, are now instead getting absorbed by Earth, as shown by the graph below (by Wipneus).

Over the past 365 days, most of the Arctic has been more than 2.5°C or 4.5°F warmer than it was in 1981-2010, as the image on the right illustrates. Note also the anomalies around Antarctica. Decline of the snow and ice cover contributes strongly to these temperature anomalies.

When looking at albedo changes, sea ice area is an even more critical measure than sea ice extent. For a discussion of the difference between area and extent, see this NSIDC page. The image below shows trends for both Arctic and Antarctic sea ice area pointing downward.

When looking at sea ice volume, zero sea ice in September 2017 is within the margins of the trendline below on the right.

[ Arctic sea ice, gone by Sept. 2017? ]

Given the speed at which many feedbacks can kick in and the interaction between warming elements, Arctic sea ice volume could be zero by September 2017.

Arctic sea ice is at a record low volume for the time of the year (see graph below by Wipneus). This means that there is very little sea ice left to act as a buffer this year. Therefore, heat that won't be consumed in the process of melting the ice will instead speed up Arctic warming.

As said - less sea ice additionally makes that less sunlight will be reflected back into space, and that instead more heat will speed up Arctic warming.

As the sea ice gets thinner, it becomes more fragile. Furthermore, changes to the Jet Stream can fuel strong winds and waves, which are also more likely to hit the ice as the size of the open water increases.

The satellite image below of the Beaufort Sea shows that the sea ice is cracked in many places and broken into pieces by winds, waves, currents and ocean heat. A huge crack can be seen running along the Canadian Archipelago toward Greenland (bottom right on the image).

An animation (1.3 MB) is added at the end of this post showing the sea ice breaking into pieces in the Beaufort Sea from April 26 to May 10, 2017. It illustrates that a combined force of winds, waves, currents and ocean heat can break even the thicker ice into pieces, with the danger that all ice can be pushed out of the Arctic Ocean.

3. Temperatures on land

High temperatures on land will affect the Arctic in a number of ways. What kind of temperatures can be expected over the coming months, which are so critical for Arctic sea ice?

- Heatwaves

Heatwaves over the continents can more easily extend over the Arctic Ocean as the Northern Polar Jet Stream becomes more wavy. Heatwave conditions are more likely to occur as the jet stream is changing due to accelerated warming of the Arctic.

- Wildfires

High temperatures on land can also cause wildfires that can in turn cause huge quantities of emissions, including soot that when settling on snow and ice, can strongly speed up melting. The image below shows carbon dioxide as high as 607 ppm and carbon monoxide as high as 24.84 over Laos on May 4, 2017.

- Warm water from rivers flowing into the Arctic Ocean

Furthermore, high temperatures on land will warm up the water of rivers flowing into the Arctic Ocean.

- El Niño

An El Niño event can dramatically boost temperatures of the atmosphere. What are the projections for an El Niño in 2017? The image on the right, by the ECMWF (European Centre for Medium-Range Weather Forecasts), indicates an El Niño that is gaining strength.

4. Emissions and Greenhouse Gas Levels

Continued emissions and high greenhouse gas levels are responsible for warming of the planet. Have efforts to cut emissions been successful? Is growth in greenhouse gas levels slowing down? The image below shows accelerating growth of carbon dioxide levels recorded at Mauna Loa, Hawaii.

The image below shows carbon dioxide levels recorded at Barrow, Alaska.

The image below shows methane levels at Barrow, Alaska.

In conclusion, indications are that warming in the Arctic will continue in 2017, which spells bad news for Arctic sea ice and for the world at large, as discussed in earlier posts.

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


The animation below shows the break up of the sea ice in the Beaufort Sea from April 26 to May 10, 2017. It illustrates that a combined force of winds, waves, currents and ocean heat can break even the thicker ice into pieces, with the danger that all ice can be pushed out of the Arctic Ocean.

An intensely warm winter and spring are melting climate records across Alaska, reports NOAA in the post 'Arctic set for record-breaking melt'. The January-April 2016 period was 11.4°F (6.4°C) warmer than the 20th century average, reports NOAA. The NOAA image below further illustrates the situation.

The sea ice is melting rapidly. Warm water from the Mackenzie River contributes to dramatic melting in the Beaufort Sea, as illustrated by the image below, showing that on May 20, 2016, the Arctic Ocean was 5°F (2.8°C) warmer than in 1981-2011 at the delta of the Mackenzie River.

The image below shows that on May 20, 2016, sea ice extent was 10.99 million square km, compared to the 12.05 million square km extent of the sea ice in May 20, 2012, as measured by JAXA. 

Sea ice reached a record minimum extent of 3.18 million square km on September 15, 2012, and chances are that the sea ice will be largely gone by September 2016.

The year 2016 is an El Niño year and insolation during the coming months of June and July is higher in the Arctic than anywhere else on Earth. Higher temperatures come with increased danger of wildfires. Greenhouse gases are at record high levels: in April and may, CO2 was about 408 ppm, with hourly peaks as high as 411 ppm (on May 11, 2016). Methane levels are high and rising, especially over the Arctic. Smoke and methane are speeding up sea ice melting, as illustrated by the image below showing smoke from wildfires in Canada extending over the Beaufort Sea (main image), in addition to high methane levels that are present over the Beaufort Sea (inset). 

Ocean heat is also very high and rising. Oceans on the Northern Hemisphere were 0.93°C (or 1.7°F) warmer in the most recent 12-months period (May 2015 through April 2016) than the 20th century average.

The image below shows sea ice extent as measured by the NSIDC, confirming that melting of the sea ice in 2016 is way ahead on previous years.

Here's an animation comparing sea surface temperatures of the North Atlantic between May 25, 2015, and May 25, 2016.

Arctic sea ice extent was 10.7 million km² on May 25, 2016, 1.1 million km² less than it was on May 25, 2012, as the update below shows.

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

Arctic sea ice extent is very low, much lower than it was in other years at this time of year. On May 11, 2016, Arctic sea ice extent was 12.328 million square km, according to the National Snow and Ice Data Center (NSIDC), while JAXA's figure for extent on May 11, 2016, was only 11.57 million square km.

[ based in image from JAXA ]

JAXA figures show that Arctic sea ice extent on May 9, 2016, was 11.68 million square km, more than 18 days ahead on 2012 and 1.1 million square km smaller than it was on May 9, 2012.

The image on the right compares the Beaufort Sea and the northern part of Alaska between May 9, 2012 and May 9, 2016. As the image illustrates, there now is a lot less ice and snow cover than there was on 2012.

The situation looks set to deteriorate further over the coming months. The image below shows temperature forecast to reach anomalies as high as 5.19°C or 9.34°F for the Arctic as a whole (forecast for May 19, 2016, 0300 UTC), with temperature anomalies at the top end of the scale forecast for Alaska and eastern Siberia.

These temperature anomalies go hand in hand with a very wavy jet stream, as illustrated by the image on the right, showing loops extending all the way over the Arctic Ocean (in particular over the Beaufort Sea), taking along warm air in their path.

At the same time, the jet stream can extend far south at other places, making that cold air is moving south, out of the Arctic.

The result is a rapidly warming Arctic, which in turn makes the jet stream even more wavier, as one out of numerous feedbacks that are all  hitting the Arctic at the same time.

The image below compares sea ice thickness between May 13, 2012, and May 13, 2016.

The image on the right shows that sea surface temperatures near Svalbard were as high as 55°F (12.8°C) on May 11, 2016, an anomaly of 21.2°F (11.8°C) from 1981-2011. In other words, the temperature of the sea surface was 1°C in that spot from 1981 to 2011, and now this spot is 11.8°C warmer.

The image below compares sea surface temperature anomalies from 1961-1990 between May 12, 2015, and May 12, 2016.

Sea surface temperatures in the Arctic Ocean are higher than they used to be, in particular in the Bering Strait, the Beaufort Sea, in Baffin Bay and the Kara Sea.

[ click on images to enlarge ]

In summary, Arctic sea ice is in a very bad shape, while ocean heat is very high and rising. Greenhouse gas levels are at record high levels, as discussed in an earlier post and as further illustrated by the image below.

The image below shows that, over the past 365 days, warming over the Arctic have been much stronger than over the rest of the world. Air temperature anomalies of more than 2.5°C (4.5°F) show up over most of the Arctic Ocean. Furthermore, as discussed above, high temperatures are forecast to hit the Arctic over the next week.

From November 2015 to April 2016, global temperatures over land and oceans were 1.48°C (or 2.664°F) higher than in 1890-1910 (left map of the image below). On land, it was 1.99°C (or 3.582°F) warmer (right map of the image below).

[ also see comments ]

Since some 0.3°C (0.54°F) greenhouse warming had already taken place by the year 1900, warming was well above the 1.5°C (or 2.7°F) guardrail the Paris Agreement had pledged wouldn't be crossed.

Given the above, chances are that the sea ice will be largely gone by September 2016.

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