High methane levels over the Arctic Ocean on February 17, 2014

Above image shows IASI methane readings over the last day or so, when levels as high as 2223 ppb were recorded.

Where does the methane come from?

On above image, methane shows up prominently along the faultline that crosses the Arctic Ocean from the northern tip of Greenland to the Laptev Sea. This indicates that the methane originated from the depths of the Arctic Ocean, where sediments contain large amounts of methane in the form of free gas and hydrates, which have become destabilized.

High methane concentrations have persistently shown up over the Arctic Ocean since October 1, 2013. On January 19, 2014, levels as high as 2363 ppb were recorded over the Arctic Ocean, as illustrated by the image below, from an earlier post.

[ from earlier post, click on image to enlarge ]

Below is a comparison of methane readings for the week from February 9 to 16, 2014, compared to the same period in 2013.

[ from earlier post, click on image to enlarge ]

The above comparison shows that there is a lot of methane over the Arctic Ocean that wasn't there last year. 

Furthermore, high methane readings show up where currents move the sea ice out of the Arctic Ocean, in areas such as Baffin Bay. This indicates that methane that is released from the seafloor of the Arctic Ocean appears to be moving underneath the ice along with exit currents and entering the atmosphere where the sea ice is fractured or thin enough to allow the methane to pass through. 

Also note that more orange areas show up on the southern hemisphere in 2014, indicating that more methane from the northern hemisphere is now spreading south beyond the equator. This in addition to indications that more methane is rising and building up at higher altitudes, as discussed in an earlier post.

Causes

What made these high releases from the seafloor of the Arctic Ocean persist for so long? At this time of year, one might have thought that the water in the Arctic Ocean would be much colder than it was, say, on October 1, 2013.

Actually, as the combination image below shows, sea surface temperatures have not fallen much at the center of the Arctic Ocean between early October, 2013 (left) and February 17, 2014 (right). In the area where these high methane concentrations occured, sea surface temperatures have remained the same, at about zero degrees Celsius.

[ click on image to enlarge ]

The above comparison image shows that, while surface temperatures in the Atlantic Ocean may have fallen strongly with the change of seasons, surface temperatures in the Arctic Ocean have changed only little.

In this case of course, what matters more than surface temperatures are water temperatures at greater depth. Yet, even here temperatures in the Arctic Ocean will have decreased only slightly (if at all) compared to early October 2013, since the Gulf Stream has continued to push warmer water into the Arctic, i.e. water warmer than the water in the Arctic Ocean, so the heating impact of the Gulf Stream continues. Also, sea surface temperature anomalies along the path of the Gulf Stream continue to be anomalously high, as the image below shows.

The situation looks even more grim on the Climate Reanalyzer image below, showing sea surface temperature anomalies that are far more profound in the Arctic Ocean.

Note also that, as the sea ice extent increased, there have been less opportunities for the heat to evaporate on the surface and for heat to be transferred from the Arctic Ocean to the air.

Finally, what matters a lot is salinity. The combination image below compares salinity levels between October 1, 2013 (left), and February 17, 2014 (right).

[ click on image to enlarge ]

Salinity levels were low on October 1, 2013, as a lot of ice and snow had melted in the northern summer and rivers had carried a lot of fresh water into the Arctic Ocean. After October 1, 2013, little or no melting took place, yet the Gulf Stream continued to carry waters with higher salt levels from the Atlantic Ocean into the Arctic Ocean.

Annual mean sea surface salinity

Seawater typically has a salinity level of over 3%; it freezes and melts at about −2°C (28°F). Where more saline water from the Atlantic Ocean flows into the Arctic Ocean, the water in the Arctic Ocean becomes more saline. The freezing and melting point of fresh water (i.e. zero salinity) is 0°C (or 32°F). More salinity makes frozen water more prone to melting, i.e. at temperatures lower than 0°C, or as low as −2°C.

As the salinity levels of the water on the seafloor of the Arctic Ocean increased, the ice that had until then held the methane captive in hydrates on the seafloor of the Arctic Ocean started to melt. Indeed, the areas in the Arctic Ocean where the high methane releases occurred on January 14, 2014 (top image) show several practical salinity units (psu) increase since October 1, 2013.

Higher salinity levels are showing up closer to the faultline that runs through the Arctic Ocean from the top of Greenland to the Laptev Sea.

Extreme weather strikes around the globe - update

As the weather gets more extreme, disaster strikes around the globe. The Guardian reports three people killed as storms continue to batter southern UK. The Vancouver Sun reports that a U.S. Northeast snowstorm kills 25. And the Sacramento Bee reports Six dead and 1,000 injured in fresh Japan snow storm.

What is the story behind these extreme weather events? The image below tells the story. The Arctic has been much warmer than it used to be, due to numerous feedbacks that accelerate warming in the Arctic. This reduces the temperature differential between the Arctic and lower latitudes, which changes the Jet Stream and Polar Vortex, in turn making the weather at many places ever more extreme.

 earlier forecasts by cci-reanalyzer.org

Above image illustrates the situation, showing an Arctic Ocean that is warmer than the higher latitudes of the Asian and North American continents.

Arctic sea ice has meanwhile reached record lows, as illustrated by the image below.

The situation can be expected to get even worse. The image below shows sea ice extent, as measured by the NSIDC, which is one day ahead compared to above image.

Below, two regular contributors to the Arctic-news blog comment on the situation.

Extreme weather strikes around the globe

Editorial note: this post has meanwhile been updated as Extreme weather strikes around the globe update.

As the weather gets more extreme, disaster strikes around the globe.

Here's a snapsnot from today's news. In London, the BBC reports, flooded homes along the River Thames are being evacuated and thousands more are at risk. In Japan, reports Reuters, eleven people died, more than a thousand were injured and tens of thousands lost power when the worst snowstorm in decades hit Tokyo and areas around the Japanese capital before heading north to blanket the tsunami-hit Pacific coast. Many countries in the Middle East were hit by snow. The BBC reports that heavy snow in northern Iran has left around 480,000 homes without power and some towns and villages cut off.

What is causing these extreme weather events? The image below tells the story. While at times it has been cold at many places around the world, when averaged over the past 30 days, temperatures around the globe have actually been several degrees higher than they used to be. The Arctic has been hit hardest, with anomalies as high as 21°C over this 30 day period. This affects the Jet Stream and Polar Vortex, which in turn is making the weather ever more extreme.

The situation is further illustrated by the cci-reanalyzer.org forecasts below.

And while the sea ice didn't look too bad at the start of the year, growth has meanwhile stopped, as illustrated by the image below.

Added below are two videos by Paul Beckwith, further discussing the situation.

Editor's note: Reanalysis of temperature anomaly Jan 12 - Feb 10, 2014.

Meanwhile, I've added another image (above), created with NOAA's reanalysis, which compares temperatures to a larger dataset, and the colors look a lot different, so NOAA may indeed have mixed the colors up somewhat in the initial image, as Albert suggested at the Facebook discussion (click on image below).

Anyway, the point made in the post remains, i.e. that as global warming continues, warming in the Arctic accelerates more rapidly than at lower latitudes, which weakens the polar vortex and jet stream in a self-reinforcing feedback that causes the Arctic to warm up even further compared with lower latitudes.

As said, the situation calls for comprehensive and effective action, as discussed at the Climate Plan blog.

High methane readings over Greenland

High methane readings have been recorded over Greenland since the start of February 2014. The image below shows methane readings of 1950 ppb and higher in yellow on February 9, 2014.

The animation below shows that high methane readings (1950+ ppb in yellow) have been showing up over Greenland since the start of February 2014.

[ Note: this animation is a 3.28 MB file that may take some time to fully load ]

What could have caused these high methane readings? The persistence with which the methane shows up over Greenland indicates that it did indeed originate from Greenland.

The above animation also illustrates that high methane readings show up every other image. The IASI readings come from a satellite that is orbiting the poles twice daily, with a 12-hour interval, so the satellite passes the North Pole twice every day. This makes that the images follow a day-versus night pattern, indicating that the high methane readings follow a circadian rhythm, suggesting a pattern that is in line with temperature differences between day and night.

There often is a difference in methane readings between day and night, but rarely is it as distinct as is currently the case over Greenland. And indeed, more is currently happening to temperatures over Greenland than mere differences in temperature between day and night.

As discussed in earlier posts such as this one, the once-common temperature difference between the Arctic and lower latitudes has been shattered, and this is weakening the Jet Stream and the Polar Vortex, in turn making it easier for cold air to flow down to lower latitudes and for warmer air to enter the Arctic. As a result, temperatures over Greenland can go from one extreme to another and back, as illustrated by the image with selected cci-reanalyzer.org forecasts below.

[ click on image to enlarge ]

Above image shows that, in some areas over Greenland, temperature anomalies may go down as low as as minus 20 degrees Celsius one day, then climb as high as 20 degrees Celsius a few days laters, to hit temperature anomalies as low as minus 20 degrees Celsius again some days later. These are swings of 40 degrees Celsius that can hit an area over the course of a few days. 

This could explain the methane over Greenland. Methane is present in the Greenland ice sheet in the form of hydrates and free gas. These huge temperature swings are causing the ice to expand and contract, thus causing difference in pressure as well as temperature. The combined shock of wide pressure and temperature differences is causing movement and fractures in the ice allowing methane to rise to the surface and enter the atmosphere.

The image below puts things in perspective, comparing methane over Greenland with methane over the Arctic Ocean.

Above image shows that the amounts of methane over Greenland are huge, while methane is still being released from the seafloor of the Arctic Ocean, in particular along the faultline that runs from the north of Greenland to the Laptev Sea. 

Few people seem to have anticipated these methane releases from the mountains of Greenland. Even worse, similar processes could be going at times on Antarctica, the Himalayas and the Qinghai-Tibet Plateau. I warned about this danger, e.g. in the May 2013 post Is Global Warming breaking up the Integrity of the Permafrost?. The danger that methane will be released in large (and growing) quantities from hydrates and free gas contained in the ice over mountains appears to have been ignored by the IPCC, which puts more weight on my estimate that methane release from hydrates currently amounts to 99 Tg annually, vastly more than the most recent IPCC estimates of 6 Tg per year. 

Without action on climate change, these methane releases threaten to rise even further and cause runaway global warming. This calls for comprehensive and effective action as discussed at the Climate Plan blog.