The Methane Monster

At no time in the past did humans exist under conditions that we are facing now, no matter how far back you go in history.

Global mean methane levels as high as 1840 parts per billion were recorded on August 4, 2015. This is the highest mean level since records began and this new record is likely to be superseded by even higher levels soon.

The carbon dioxide that is released now will only reach its peak impact a decade from now. Methane's high immediate impact makes it more important than carbon dioxide emissions in driving the rate of global warming over the coming decade.

The Pacific Ocean is very warm at the moment. Warm water flows from the Pacific Ocean through the Bering Strait into the Arctic Ocean. Sea surface temperatures in the Bering Strait were as high as 20.5°C (or 69.1°F) on August 4, 2015. That is 8.7°C (or 15.6°F) warmer than the water used to be. Sea surface temperatures as high as 11.8°C (53.2°F) were recorded in between Greenland and Svalbard on August 7, 2015, an anomaly of 8.5°C (15.3°F).

[ click on image to enlarge ]

The danger is that further warming will cause collapse of the sea ice, which in turn will lead to even more rapid warming of the Arctic Ocean, while the presence of more open water will also increase the opportunity for powerful storms to develop that can mix high sea surface temperatures all the way down to the seafloor, resulting in destabilization of sediments and triggering releases of methane that can be contained in such sediments in huge amounts.

Methane releases from the seafloor of the Arctic ocean threaten to cause rapid local warming that in turn will trigger further methane releases, in a vicious cycle of runway warming that could destroy habitat for humans within decades.

[ click on image to enlarge ]

The situation is dire and calls for comprehensive and effective action as discussed at the Climate Plan at the Arctic-News Blog.


References

-  Sea surface temperatures in the Bering Strait on August 4, 2015. 

http://arctic-news.blogspot.com/2015/08/record-high-methane-levels.html

- Sea surface temperatures in between Greenland and Svalbard on August 7, 2015.
http://earth.nullschool.net/#2015/08/07/0000Z/ocean/surface/currents/overlay=sea_surface_temp_anomaly/orthographic=18.75,79.02,3000

- Maximum warming occurs about one decade after a carbon dioxide emission, by Katharine L Ricke and Ken Caldeira (2014)
http://iopscience.iop.org/1748-9326/9/12/124002/article

- Methane's Global Warming Potential

http://arctic-news.blogspot.com/p/faq.html#13

THE METHANE MONSTER - by Sam Carana At no time in the past did humans exist under conditions that we are facing now,...
Posted by Sam Carana on Sunday, August 9, 2015

Record High Methane Levels

[ click on images to enlarge ]

As the top image shows, sea surface temperature anomalies in the Bering Strait on August 4, 2015, were as high as 8.7°C (15.6°F). Such high anomalies are caused by a combination of ocean heat, of heatwaves over Alaska and Siberia extending over the Bering Strait, and of warm river water run-off.

As the image on the right shows, sea surface temperatures in the Bering Strait were as high as 20.5°C (69.1°F) on August 4, 2015.

As warm water flows through the Bering Strait into the Arctic Ocean, it dives under the sea ice and becomes harder to detect by satellites that typically measure water temperatures at the surface, rather than below the surface.

The image below shows sea surface temperature anomalies from 1971 to 2000, for August 6, 2015, as visualized by Climate Reanalyzer.

Climate Reanalyzer applies a mask over sea-ice-covered gridcells, reducing anomalies in such cells to zero.

Below is a NOAA image, for August 5, 2015, also with anomalies from 1971 to 2000.

Below is another NOAA image, showing anomalies for August 6, 2015. Because the base period is 1961 to 1990, the anomalies are higher. Nonetheless, the yellow areas that feature around the North Pole on above image do not show up on the image below.

In other words, looking at sea surface temperatures alone may lead to underestimations of the temperatures of the water underneath the sea ice. Keeping that in mind, have a look again at the high anomalies on the image below.

The danger is that further decline of the sea ice will lead to rapid warming of the Arctic Ocean, while the presence of more open water will also increase the opportunity for strong storms to develop that can mix high sea surface temperatures all the way down to the seafloor, resulting in destabilization of sediments and triggering releases of methane that can be contained in such sediments in huge amounts.

The image below shows that global mean methane levels as high as 1840 parts per billion (ppb) were recorded on August 4, 2015. Peak methane levels that day were as high as 2477 ppb.

This peak level of 2477 ppb isn't the highest recorded the year. As the image below shows and as discussed in a previous post, methane levels as high as 2845 ppb were recorded on April 25, 2015. The average of the daily peaks for this year up to now is 2355 ppb. Very worrying about the above image are the high levels of methane showing up over the Arctic Ocean.

As above image also shows, the mean methane level of 1840 ppb is in line with expectations, as methane levels rise over the course of the year, to reach a maximum in September. This mean level of 1840 ppb is higher than any mean level since records began.

The image below shows all the World Meteorological Organisation (WMO) annual means that are available, i.e. for the period 1984 through to 2013.

As above image shows, a polynomial trendline based on these WMO data (for the period 1984 through to 2013) points at a doubling of mean global methane levels by about 2040. The added NOAA data are the highest mean in 2014, i.e. 1839 ppb recorded on September 7, 2014, and the above-mentioned level of 1840 ppb recorded on August 4, 2015.

As said, mean global methane levels last year reached its peak in September and the same is likely to occur this year. In other words, this new record is likely to be superseded by even higher levels soon.

The image on the right shows the steady rise of the highest mean daily methane levels that have been recorded recently, indicating that a continued rise can be expected that would put another highest mean level for 2015 on the trendline of above image soon.

Again, the danger is that a warming Arctic Ocean will trigger further methane releases from the seafloor, leading to rapid local warming that in turn will trigger further methane releases, in a vicious cycle of runway warming.

As illustrated by the image on the right, at a 10-year timescale, the current global release of methane from all anthropogenic sources exceeds all anthropogenic carbon dioxide emissions as agents of global warming.

Over the next decade or so, methane emissions are already now more important than carbon dioxide emissions in driving the rate of global warming, and this situation looks set to get worse fast.

Unlike carbon dioxide, methane's GWP does rise as more of it is released. Higher methane levels cause depletion of hydroxyl, which is the main way for methane to be broken down in the atmosphere.

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

The image shows all the World Meteorological Organisation (WMO) annual means that are available, i.e. for the period...
Posted by Sam Carana on Friday, August 7, 2015

Arctic Sea Ice Collapse Threatens - Update 3

The image below is based on a nullschool.net forecast for August 6, 2015, run on August 2, 2015. It shows temperatures as high as 26.4°C (or 79.4°F) in the north of Canada (green circle). The inset, based on a Climate Reanalyzer forecast for that date, shows that this is as much as 20°C (or 36°F) higher than temperatures that were common in the area only recently, i.e. from 1979-2000.

The satellite image below, captured on August 2, 2015, shows a close-up of the area, with the green circle in the same location as on above image.

Above image shows that there still is some solid ice present to the right of the green circle. This ice may not be able to survive such high temperatures for long. Furthermore, above image shows what looks like smoke plumes from wildfires to the left of the green circle, another sign of the high temperatures in the area and another feedback that will accelerate decline of the snow and ice cover.

Disappearance of sea ice thicker than 4 meters is now taking place north of Canada and Greenland. It looks set to virtually disappear soon, as shown by the 30-day Naval Research Laboratory animation below, ending with a forecast up to August 10, 2015.

In my experience, sea ice thickness hasn't looked this bad for this time of the year since records began, especially when taking the loss of multi-year ice into account. Until now, the thicker multi-year sea ice used to survive the melting season, giving the sea ice strength for the next year, by acting as a buffer to absorb heat that would otherwise melt away the thinner ice. Without multi-year sea ice, the Arctic will be in a bad shape in coming years. Absence of thick sea ice makes it more prone to collapse, and this raises the question whether a collapse could occur not merely some years from now, but even this year.

Above image below shows sea surface temperature anomalies in the Arctic on August 2, 2015.

Greenland's dramatic loss of ice mass over the past few years and the subsequent meltwater may have caused the sea ice to be larger than it would otherwise have been.

Nonetheless, this has not halted the overall decline of the sea ice. As the image on the right shows, sea ice area now is about as low for the time of the year as it was for the three lowest years on record. Furthermore, thick sea ice is shattered if not gone altogether in many places. Meanwhile, ocean heat is at a record high and there's an El Nino that's still gaining strength.

In conclusion, Arctic sea ice looks set to take a further battering over the next few weeks and could end up at a record low around half September 2015. If things get really bad, sea ice collapse could occur and the remaining pieces of sea ice could be driven out of the Arctic Ocean altogether by storms, resulting in a blue ocean event as early as September this year.

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

Arctic sea ice area on July 31, 2015.
Posted by Sam Carana on Sunday, August 2, 2015

Arctic Sea Ice Collapse Threatens - Update 2

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

Due to warm ocean waters and to heatwaves on land that extended over the Arctic Ocean, while warming up rivers ending into the Arctic Ocean, the sea ice has taken a battering over the past few weeks, as illustrated by the images below.

Above image shows the last bit of thick (5 m) sea ice in the Canadian Archipelago, which became dislodged on July 8, 2015. It looks set to be virtually gone by August 7, 2015, according to the 30-day Naval Research Laboratory animation below, and as also discussed in greater detail in a recent post.

The situation at the north-eastern tip of Greenland doesn't look much better, as illustrated by the image below.

The comparison image below also shows the north-eastern tip of Greenland on July 5, 2015 (top), and on July 31, 2015 (bottom). The bottom image shows water in many places, pushing the last pieces of thick ice into the Wandel Sea and Fram Strait .

[ click on images to enlarge ]

Until now, the thicker multi-year sea ice used to survive the melting season, giving the sea ice strength for the next year, by acting as a buffer to absorb heat that would otherwise melt away the thinner ice. Without multi-year sea ice, the Arctic will be in a bad shape in coming years. 

[ click on images to enlarge ]

What caused the dramatic melting of this thick ice? The left panel of above image shows temperatures. On July 29, 2015, temperatures as high as 23.1°C (or 73,7°F) were recorded on the north coast of Victoria Island, in the Canadian Archipelago (green circle where the arrow points at). The satellite image on the right, captured that same day, shows that hardly any ice was left in the waters surrounding the area.

So, will the sea ice collapse this year? Consider the following four points:

Volume - The image on the top right shows sea ice volume as calculated by PIOMAS at the University of Washington. It shows that in June, volume was less than 2015 in only four years, i.e. 2010 through to 2013. The situation has deteriorated much in July 2015, and looks set to deteriorate even further.

Thickness - Volume is calculated by looking at both thickness and extent. Thickness is looking much worse than it did in the years 2012 through to 2014, as illustrated by above image.

In my experience, sea ice thickness hasn't looked this bad for this time of the year since records began, especially when taking the loss of multi-year ice into account, as also illustrated by the full-width above image.


Extent - Sea ice extent on July 31 was only outside the 2 standard deviations (shaded area) in the years 2007, 2011 and 2012, as illustrated by the image mid right. The dark blue line marks the 2015 extent, with the dot indicating extent on July 31, 2015.

Area - Similarly, Arctic sea ice area is illustrated by the image on the right. For a description of the difference between extent and area, view this NSIDC FAQ page. The bottom right image marks Arctic sea ice area as on July 30, 2015. The yellow marker indicates the situation for the year 2015 on this date. The only years with less sea ice area at this time of the year were 2007, 2011 and 2012.

Also consider that 2015 features very high sea surface temperatures and an El Niño that is still gaining in strength. Thick sea ice appears to be shattered, as illustrated by the satellite images. In conclusion, sea ice looks set to take a further battering over the next few weeks and could end
up at a record low thickness, extent, area and volume around half September 2015.

With that in mind, let's take a look at the image below.

Above image shows a trendline (shaded area) based on satellite data from 1979-2014, with annual minimum volume figures calculated by PIOMAS. The shaded area points at a total disappearance of the sea ice as early as September 2018. The width of the shaded area reflects natural variability, but natural variability could be wider than that, as illustrated by the fact that minimum volume in the years 2007, 2010, 2011 and 2012 was lower than the shaded area. In other words, disappearance of the sea ice could occur even earlier than September 2018 and if things get really bad, collapse could even occur as early as September this year.

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

Will the sea ice collapse this year? Firstly, consider that sea ice volume now hasn't been this bad for any day in July...
Posted by Sam Carana on Friday, July 31, 2015