Saturday, April 26, 2014

M5.1 Earthquake hits Greenland Sea

An earthquake with a magnitude of 5.1 on the Richter scale hit the Greenland Sea on April 26, 2014, at 03:55:33 UTC at a depth of 10.00 km (6.21 mi). The epicenter of the earthquake is located right on the faultline that crosses the Arctic Ocean, at 73.479°N 7.974°E, some 567km (352mi) SSW of Longyearbyen, Svalbard.

[ click on image to enlarge ]
This follows four further recent earthquakes close to Svalbard or on the faultline north of Greenland, as indicated on above map. All these earthquakes struck at a depth of 10.00 km (6.21 mi).

Some of these earthquakes have also been discussed in earlier posts:
M4.6 - North of Franz Josef Land, 2014-04-13 02:12:19 UTC, also discussed in this post
M4.2 - North of Franz Josef Land, 2014-04-04 07:01:30 UTC
M4.4 - 262km NE of Nord, Greenland, 2014-04-22 10:30:23 UTC, also discussed in this post
M4.3 - 148km SSE of Longyearbyen, Svalbard, 2014-04-24 08:33:06 UTC
M5.1 - Greenland Sea, 2014-04-26 03:55:33 UTC
M4.5 - Gakkel Ridge, 2014-03-06 11:17.17.0 UTC, also discussed in this post

There have been a large number of earthquakes around Greenland since early 2014, as illustrated by the image below. This could be an indication of isostatic rebound, as also discussed in this earlier post.

[ click on image to enlarge ]

As melting of the Greenland Ice Sheet speeds up, isostatic rebound could cause earthquakes around Greenland to become stronger and occur more frequently. Earthquakes in this region are very worrying, as they can destabilize hydrates contained in the sediment under the seafloor of the Arctic Ocean. Furthermore, one earthquake can trigger further earthquakes, especially at locations closeby on the same faultline.

Tuesday, April 22, 2014

M4.4 Earthquake hits Arctic Ocean north of Greenland

An earthquake with a magnitude of 4.4 on the Richter scale hit the Arctic Ocean north of Greenland on April 22, 2014, at 10:30:23 UTC at a depth of 10.00 km (6.2 mi).

[ click on image to enlarge ]
The epicenter of the quake is located right on the faultline that crosses the Arctic Ocean, at 83.328°N 4.568°W, 262km (163mi) NE of Nord, Greenland.

The earthquake follows another earthquake that hit the Arctic Ocean closeby on this faultline, on April 13, 2014, north of Franz Josef Land.

Earthquakes at this location are very worrying, as they can destabilize hydrates contained in the sediment under the seafloor of the Arctic Ocean. Furthermore, one earthquake can trigger further earthquakes, especially at locations closeby on the same faultline.

Arctic Sea Ice in Steep Descent

Arctic sea ice area is in steep descent, as illustrated by the image below. Sea ice area was only smaller at this time of the year in 2007, for all years for which satellite data are available.

[ click on image to enlarge ]
Earlier this year, on March 9, 2014, Arctic sea ice area was at a record low for the time of the year. Since then, area did show some growth for a while, to the north of Scandinavia. This growth could be attributed largely to strong winds that made the sea ice spread with little or no growth in volume. The 30-day Naval Research Laboratory animation below shows recent sea ice speed and drift.


Indeed, sea ice volume in March 2014 was the 2nd lowest on record. Only March 2011 had a lower volume as discussed in a recent post. The 30-day Naval Research Laboratory animation below shows recent sea ice thickness. 



Low sea ice volume and area jointly suggest there could be a total collapse of the sea ice later this year, in line with observation-based non-linear trends. For years, this blog has warned that observation-based projections point at Arctic sea ice disappearance within years, with dire consequences for the Arctic and for the world at large.

As said, winds are responsible for much of sea ice variability, and winds could either slow down or speed up such a collapse. On this point, it's good to remember what Prof. Peter Wadhams said in 2012:
". . apart from melting, strong winds can also influence sea ice extent, as happened in 2007 when much ice was driven across the Arctic Ocean by southerly winds. The fact that this occurred can only lead us to conclude that this could happen again. Natural variability offers no reason to rule out such a collapse, since natural variability works both ways, it could bring about such a collapse either earlier or later than models indicate.

In fact, the thinner the sea ice gets, the more likely an early collapse is to occur. It is accepted science that global warming will increase the intensity of extreme weather events, so more heavy winds and more intense storms can be expected to increasingly break up the remaining ice, both mechanically and by enhancing ocean heat transfer to the under-ice surface."
The image on the right, produced with NOAA data, shows mean coastal sea surface temperatures of over 10°C (50°F) in some areas in the Arctic on August 22, 2007.

In shallow waters, heat can more easily reach the bottom of the sea. In 2007, strong polynya activity caused more summertime open water in the Laptev Sea, in turn causing more vertical mixing of the water column during storms in late 2007, found a 2011 study, and bottom water temperatures on the mid-shelf increased by more than 3°C (5.4°F) compared to the long-term mean.

Another study found that drastic sea ice shrinkage causes increase in storm activities and deepening of the wind-wave-mixing layer down to depth ~50 m (164 ft) that enhance methane release from the water column to the atmosphere. Indeed, the danger is that heat will warm up sediments under the sea, containing methane in hydrates and as free gas, causing large amounts of this methane to escape rather abruptly into the atmosphere.

Such warming would come on top of ever-warmer water that is carried by the Gulf Stream into the Arctic Ocean and that has already been blamed for large methane releases from the seafloor of the Arctic Ocean last year.

The prospect of an El Niño event, as discussed in an earlier post, makes the situation even more dire.

The consequences of sea ice collapse will be devastating, as all the heat that previously went into transforming ice into water will be asbsorbed by even darker water, from where less sunlight will be reflected back into space. The danger is that further warming of the Arctic Ocean will trigger massive methane releases that could lead to extinction at massive sclae, including extinction of humans.

Hopefully, more people will realize the urgency of the situation and support calls for comprehensive and effective action as discussed at the Climate Plan blog.

Wednesday, April 16, 2014

Near-Term Human Extinction

Global Warming and Feedbacks

Is there a mechanism that could make humanity go extinct in the not-too-distant future, i.e. within a handful of decades?

Most people will be aware that emissions due to human activity are causing global warming, as illustrated by the arrow marked 1 in the image on the left. Global warming can cause changes to the land, to vegetation and to the weather. This can result in wildfires that can in turn cause emissions, thus closing the loop and forming a self-reinforcing cycle that progressively makes things worse.

Furthermore, less forests and soil carbon also constitute a decrease in carbon sinks, resulting in carbon that would otherwise have been absorbed by such sinks to instead remain in the atmosphere, thus causing more global warming, as illustrated by the additional downward arrow in the image on the right. In conclusion, there are a number of processes at work that can all reinforce the impact of global warming.

Emissions can also contribute more directly to land degradation, to changes in vegetation and to more extreme weather, as indicated by the additional arrow pointing upward in the image on the right. A recent study by Yuan Wang et al. found that aerosols formed by human activities from fast-growing Asian economies can cause more extreme weather, making storms along the Pacific storm track deeper, stronger, and more intense, while increasing precipitation and poleward heat transport.

Accelerated Warming in the Arctic

Similar developments appear to be taking place over the North Atlantic. Huge pollution clouds from North America are moving over the North Atlantic as the Earth spins. In addition, the Gulf Stream carries ever warmer water into the Arctic Ocean. As the image below shows, sea surface temperature anomalies at the highest end of the scale (8 degrees Celsius) are visible off the coast of North America, streching out all the way into the Arctic Ocean.


As said, feedbacks as are making the situation progressively worse. Feedback loops are causing warming in the Arctic to accelerate. Warming in the Arctic is accelerating with the demise of the snow and ice cover in the Arctic, and this is only feedback #1 out out many feedbacks that are hitting the Arctic, as described in an earlier post. As the temperature difference between the equator and the Arctic decreases, the Jet Stream is changing, making it easier for cold air to move out of the Arctic and for warm air from lower latitudes to move in (feedback #10).


Abrupt Climate Change leading to Extinction at Massive Scale

The danger is that, as temperatures over the Arctic Ocean warm up further and as the Gulf Stream carries ever warmer water into the Arctic Ocean, large quantitities of methane will erupt abruptly from the seafloor of the Arctic Ocean, adding a third kind of warming, runaway warming resulting in abrupt climate change, and leading to mass death, destruction and extiction of species including humans.

Persistence of such a progression makes it inevitable that the rest of Earth will follow the huge temperature rises in the Arctic. Massive wildfires will first ignite across higher latitudes, adding further greenhouse gas emissions and causing large deposits of soot on the remaining snow and ice on Earth, with a huge veil of methane eventually spreading around the globe. The poster below, from an earlier post, illustrates the danger.

[ click on image to enlarge - note that this is a 1.8 MB file that may take some time to fully load ]
Views by Contributors

How likely is it that the above mechanism will cause human extinction within the next few decades? What views do the various contributors to the Arctic-news blog have on this?

Guy McPherson has long argued that, given the strengths of the combined feedbacks and given the lack of political will to take action, near-term human extinction is virtually inevitable.

In the video below, Paul Beckwith responds to the question: Can climate change cause human extinction?


Further contributors are invited to have their views added to this post as well. While many contributors may largely share Paul Beckwith's comments, it's important to highlight that contributors each have their own views, and this extends to their preference for a specific plan of action.

Geo-engineering

One of the more controversial issues is the use of geo-engineering. Guy McPherson doesn't believe geo-engineering will be successful. In the video below, Paul Beckwith gives his (more positive) views on this.


I must admit that the lack of political will to act is rather depressing, especially given the huge challenges ahead. So, I can understand that this can make some of us pessimistic at times. Nonetheless, I am an optimist at heart and I am convinced that we can get it right by giving more support to a Climate Plan that is both comprehensive and effective, as discussed at ClimatePlan.blogspot.com

Monday, April 14, 2014

M4.5 Earthquake hits Arctic Ocean

An earthquake with a magnitude of 4.5 on the Richter scale hit the Arctic Ocean on April 13, 2014, at 02:12:19 UTC at a depth of 10.00 km (6.21 mi).


The epicenter of the quake is located right on the faultline that crosses the Arctic Ocean, at 86.687°N 45.393°E, some 800 km north of Franz Josef Land.

Earthquakes at this location are very worrying, as they can destabilize hydrates contained in the sediment under the seafloor of the Arctic Ocean. Furthermore, one earthquake can trigger further earthquakes, especially at locations closeby on the same faultline.

Saturday, April 12, 2014

Methane buildup in the atmosphere

Levels of carbon dioxide (CO2) in the atmosphere are now firmly above the 400 parts per million (ppm) level, as illustrated by the graph below, from keelingcurve.ucsd.edu.
As above graph shows, levels of CO2 go up and down with the seasons. Even higher levels are expected to be reached in May 2014. Importantly, 400 ppm is 143% its pre-industrial peak levels of 280 ppm.

Levels of methane (CH4) in the atmosphere are rising even faster. According to IPCC AR5, methane levels were 1798 ppb in 2010 and 1803 ppb for 2011. A graph included in an earlier post shows historic levels of CH4, CO2 and N2O levels, highlighting methane's steep rise (now some 250% its pre-industrial level). The graph below, based on a plot by NOAA, shows the rise of methane over the past few decades and also shows that methane levels similarly go up and down with the seasons.

Globally, IPCC/NOAA figures suggest that abundance of methane in the atmosphere did reach 1814 ppb in 2013 and is rising with some 5 to 6 ppb annually. IASI data show that - at the hight of the northern summer, in August 2013 - mean methane levels rose strongly, to levels well above 1800 ppb, as also discussed in posts such as this one.

Next to seasonal variations, methane levels also differ depending on altitude. Often, when mean methane values are given, readings at 14,383 feet altitude are used, as methane typically reaches its highest levels at this altitude.

The image on the right compares methane levels for 2013 and 2014 at this altitude over six recent days, with a.m readings and p.m. readings for each day.

Around this time of year in 2013, as the graph shows, methane levels went through the 1800 ppb mark. The same thing occurred this year, while levels have meanwhile increased with a few ppb, so at first glance methane's rise appears to continue as anticipated by the IPCC.

While the above is very worrying, the situation may be even more dire than this. The graph below compares methane levels in 2013 and in 2014, averaged over the same six-day period (April 5 through to April 10) and at six different altitudes.

Above image indicates that, while the difference between 2013 and 2014 at lower altitudes (8,367 feet and 14,383 feet) may seem relatively small, increases at higher altitudes may be much stronger. In other words, rather than rising in a similar way across all altitudes, methane may in fact be building up much more strongly at higher altitudes.

This frightening possibility was raised a few times at this blog, such as in the altitude analysis in January 2014 and in the post Quantifying Arctic Methane, which noted that IPCC-estimates of global methane levels may rely too much on low-altitude data collected over the past few decades. Indeed, the total methane burden may already be rising much more rapidly than the IPCC is anticipating, also because methane is rising in the atmosphere, increasing the burden especially at higher altitudes, as evidenced by increasing occurence of noctilucent clouds.

The above analysis uses a limited dataset, just like the previous one, but if verified by further analysis, it could be that a dramatic rise in the presence of methane in the atmosphere is occuring without showing up at lower altitudes. This could also explain how earlier releases of methane from hydrates could have been ignored by many, i.e. relatively small increases in methane levels at relatively low altitudes may have given a false reassurance that such releases were not adding much methane to the atmosphere. Further analysis, comparing satellite data at different altitudes over the years, could give more clarity on these points.




Tuesday, April 8, 2014

March 2014 Arctic Sea Ice Volume 2nd lowest on Record

The March 2014 Arctic sea ice volume, as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center, was the 2nd lowest on record at 21.818 km³. Only March 2011 had a lower volume, at 21.421 km³, as illustrated by the graph below, by Wipneus.
Another way of depicting the continued fall of the sea ice volume is the Arctic Death Spiral below, by Andy Lee Robinson.

This puts the sea ice in a very weak position. This month, the sea ice will reach its highest volume, which may well be the lowest volume on record for April. The Naval Reserach Laboratory 30-day animation below shows recent sea ice thickness.


The lowest sea ice volume for 2014 is expected to be reached in September, and - given the shape the ice is in now - will likely be one of the lowest minima on record. In fact, there is a chance that there will be no ice left whatsoever later this year. As illustrated by the image below, again by Wipneus, an exponential curve based on annual minima from 1979 points at zero ice volume end 2016, with the lower limit of the 95% confidence interval pointing at zero ice end of 2014.
Absence of sea ice will mean that a lot of more heat will be absorbed by the Arctic Ocean.

As NSIDC.org describes, sea ice reflects 50% to 70% of the incoming energy, but thick sea ice covered with snow reflects as much as 90% of the incoming solar radiation. After the snow begins to melt, and because shallow melt ponds have an albedo of approximately 0.2 to 0.4, the surface albedo drops to about 0.75. As melt ponds grow and deepen, the surface albedo can drop to 0.15. The ocean reflects only 6% of the incoming solar radiation and absorbs the rest. Furthermore, all the heat that during the melt went into transforming ice into water will - in the absence of ice - be absorbed by the ocean as well.


Such feedbacks are causing warming to accelerate in the Arctic Ocean, much of which is very shallow and thus vulnerable to warming. The Gulf Stream can be expected to keep carrying warmer water into the Arctic Ocean. Extreme weather events such as heatwaves and cyclones could make the situation a lot worse.

Warming of the Arctic Ocean threatens to destabilize huge amounts of methane held in sediments at the seafloor, in the form of free gas and hydrates. The danger is that release of methane from the seafloor of the Arctic Ocean will warm up the Arctic even further, triggering even more methane releases, as well as heatwaves, wildfires and further feedbacks, in a spiral of runaway warming that will lead to starvation, destruction and extintion at massive scale across the globe.

In conclusion, the situation is dire and calls for comprehensive and effective action, as discussed at the climate plan blog.