Showing posts with label earthquakes. Show all posts
Showing posts with label earthquakes. Show all posts

Sunday, May 14, 2017

Earthquake east of Greenland triggers methane releases


An earthquake with a magnitude of M 4.5 on the Richter scale hit the seafloor 204 km East of Nord, Greenland, on May 8, 2017 at 04:48:53 (UTC). Location: 81.684°N 5.076°W. Depth: 10.0 km.

The inset shows that methane levels over 1950 ppb (magenta color) were recorded on the morning of May 8, 2017, by two satellites.

This is a reminder that earthquakes can destabilize methane hydrates, which can hold huge amounts of methane in sediments at the seafloor of the Arctic Ocean. As temperatures keep rising, snow and ice on Greenland and Svalbard keeps melting, taking away weight from the surface, making that isostatic rebound can increasingly trigger earthquakes on the faultline that crosses the Arctic Ocean.

Methane releases have followed earthquakes in the Arctic before, e.g. see this 2016 post, illustrating the danger of potentially huge methane releases in case of larger earthquakes in the Arctic.

Why is methane so important again? Below follow some images from the methane page


Over a 10-year timescale, methane emissions cause more warming than carbon dioxide emissions, as illustrated by the graph in the left-hand panel of above image.

Methane levels fluctuate with the time of year, higher mean levels are typically reached in September.

On September 14, 2016, methane levels at 367 mb were as high as 2697 ppb (locally), while global mean methane level was as high as 1865 ppb (above image).

On May 13, 2017, am, global mean methane levels were as high as 1844 ppb at altitudes corresponding to 383mb to 469 mb (MetOp-1 satellite), while local levels as high as 2485 ppb were recorded.

Methane levels have risen 256% from 1750 to 2015, as illustrated by the image on the right.

Growth in methane levels has been accelerating recently. Contained in existing data is a trend indicating that methane levels could increase by a third by 2030 and could almost double by 2040, as illustrated by the image below. 


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


Links

• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html

• High Methane Levels Follow Earthquake in Arctic Ocean
https://arctic-news.blogspot.com/2016/07/high-methane-levels-follow-earthquake-in-arctic-ocean.html

• Methane
https://arctic-news.blogspot.com/p/methane.html


Friday, October 17, 2014

U.S. hit by numerous earthquakes?

During the past decade from December 2004 to present, no less than 18 great (Mw ≥ 8.0) earthquakes occurred globally (~1.8 per year), compared to 71 from 1900 to mid-2004 (~0.68 per year), yielding an effective rate increase of 265%, says seismologist Thorne Lay of the University of California at Santa Cruz.

What about smaller earthquakes? As the image below illustrates, of the 1495 earthquakes that hit the world over a period of seven days up to October 17, 2014, 05:04:30, UTC, 1404 occured in the map area of the image below. However, the U.S. is over-represented, the USGS map doesn't show smaller earthquakes (under magnitude 4) outside the U.S.

[ click on image to enlarge ]
Can we expect more earthquakes to hit the U.S.? If so, why?

First of all, as said, many earthquakes do appear to hit the U.S. when looking at above image, but the above USGS map doesn't show smaller earthquakes (under magnitude 4) outside the U.S.

Nonetheless, there can be other reasons why so many earthquakes have recently hit the U.S., so let's explore some of them further.

It's a well-known phenemenon that, during the northern summer, more earthquakes do hit the Northern Hemisphere, rather than the Southern hemisphere. That's a natural phenomenon, but there can also be ways in which people can contribute to the incidence of earthquakes.

Isostatic rebound and changing stress conditions due to meltwater run-off can trigger seismic events. For months now, a huge amount of seismic activity has hit faultlines along the boundaries of the North American Plate, as earlier discussed in the earlier post Ring of Ice.

Bill McGuire, Emeritus Professor of Earth Sciences at the University College London, recently said the following in post at ClimateState.com:

“There may be a threat of submarine landslides around the margins of Greenland, which are less well explored. Greenland is already uplifting, reducing the pressure on the crust beneath and also on submarine methane hydrates in the sediment around its margins, and increased seismic activity may be apparent within decades as active faults beneath the ice sheet are unloaded. This could provide the potential for the earthquake or methane hydrate destabilisation of submarine sediment, leading to the formation of submarine slides and, perhaps, tsunamis in the North Atlantic.

We see evidence of the Earth ‘waking up’ specifically in relation to seismic activity in areas of Alaska where dramatic ice loss (up to 1km vertical thickness) has occurred over the last 100 years, and also in relation to the correlation in many high mountains terrains of increased landslide occurrence and heatwaves.

There is no unequivocal evidence for a specific volcanic response, unless the high level of recent activity at the Icelandic volcanoes is a reflection of unloading due to melting of the Vatnajokull Ice Cap. Certainly this whole region is uplifting by a few centimetres a year, so such a suggestion would not be completely unreasonable, even if we don’t (yet?) have any hard evidence.”


Particularly dangerous in this respect are earthquakes along the fault that crosses the Arctic Ocean, such as the 4.5 M earthquake indicated by the blue dot on the top map, also indicated on the map below. The danger here is that such earthquakes could destabilize methane hydrates that are highly prominent in sediments under the Arctic Ocean.

Map, created with methanetracker.org, with recent earthquakes on the northern boundery of the North American Plate
[click on image to enlarge]
As discussed in earlier posts, wild weather swings could also contribute to destabilization of methane hydrates. Furthermore, a study published this year suggests that human-caused groundwater depletion contributed to the prominence of earthquakes in California. Similar suggestions were made in a study focusing on a 2011 earthquake in Spain.

[ click on image to enlarge ]
Besides the above wild weather swings, wild weather itself could similarly be destructive. As hurricane Sandy approached the U.S. coast in 2012, the force of waves slamming into other waves shook the seafloor, which was recorded by earthquake sensors. The energy generated by Sandy was similar to small earthquakes between magnitudes 2 and 3, seismologists at the University of Utah estimated.

Did typhoon VongFong cause earthquakes around Japan? The image on the right shows earthquakes that occured around Japan during the seven days up to October 16, 2014. Again, the map doesn't show the smaller quakes, so further studies may be needed to shed more light on this.

[ click on image to enlarge ]
As above image shows, some 1500 earthquakes hit the world over a period of seven days up to October 17, 2014, 03:59:21, UTC. Of all these earthquakes, some 1300 hit the U.S. alone. This points at a further cause, i.e. fracking. A recent study has confirmed that fracking is linked to more earthquakes than previously believed.

“Earth to Obama . . .”

from: FAQs
Rob Howarth, Ph.D. and Professor of Ecology and Environmental Biology at Cornell University, comments:

“By once again failing to announce strong, decisive action to combat methane at the recent Climate Summit at the United Nations, Obama missed a major opportunity to demonstrate global leadership on climate change. Global emissions of methane equal or exceed the global emissions of carbon dioxide, when the methane emissions are converted to their equivalency for causing global warming using an integrated 10-year time period.”

Meanwhile, the EPA is still underreporting methane's Global Warming Potential, as earlier discussed at Myth #7 and despite a call by Rob Howarth and other methane experts to accurately account for warming effects of methane.

Update

Below is an updated map with more recent data, showing that over a period of 7 days up to October 18, 2014, 01:39:12 UTC, some 1400 earthquakes hit the U.S. Again, note that the USGS map doesn't show earthquakes under magnitude 4 outside the U.S.




References

- A global surge of great earthquakes from 2004-2014 amd implications for Cascadia - by Thorne Lay
https://gsa.confex.com/gsa/2014AM/webprogram/Paper242140.html

- Ring of Ice
http://arctic-news.blogspot.com/2014/08/ring-of-ice.html

- Methane hydrate destabilisation is clearly a real worry, particularly in the context of warming ocean waters in the East Siberian Continental Shelf
http://climatestate.com/2014/10/16/methane-hydrate-destabilisation-is-clearly-a-real-worry-particularly-in-the-context-of-warming-ocean-waters-in-the-east-siberian-continental-shelf

- Wild Weather Swings
http://arctic-news.blogspot.com/2014/10/wild-weather-swings.html

- Uplift and seismicity driven by groundwater depletion in central California
http://www.nature.com/nature/journal/v509/n7501/full/nature13275.html

- The 2011 Lorca earthquake slip distribution controlled by groundwater crustal unloading
http://www.nature.com/ngeo/journal/v5/n11/full/ngeo1610.html

- Superstorm Sandy's Energy Jolted U.S., Detected By Earthquake Sensors In Pacific Northwest
http://www.huffingtonpost.com/2013/04/18/superstorm-sandy-energy_n_3112814.html

- Sandy Shook US Like an Earthquake
http://www.livescience.com/24726-sandy-earthquake-movie.html

- Fracking Linked to More Ohio Earthquakes
http://www.livescience.com/48294-fracking-caused-ohio-earthquakes.html

- Characterization of an Earthquake Sequence Triggered by Hydraulic Fracturing in Harrison County, Ohio
http://srl.geoscienceworld.org/content/early/2014/10/09/0220140127.extract

- Climate change, Obama, and methane
http://thehill.com/blogs/congress-blog/energy-environment/219704-climate-change-obama-and-methane




Saturday, August 30, 2014

Ring Of Ice



Prominence of earthquakes in North America and around Greenland has prompted a team of researchers led by Arctic-news blog editor Sam Carana to coin the phrase “Ring Of Ice” to describe what they see happening in the Arctic.

“Melting of ice in north Canada and on Greenland is causing pressure changes, resulting in seismic activity”, explains Sam Carana.

Heavy seismic activity is ocurring along the faultlines that constitute the border of the North American Plate, similar to the the heavy activity along the Ring Of Fire around the Pacific Ocean.

Seismic activity roughly follows the borders of the North American Plate, which includes Greenland. However, where the major fault bends away to the west following the Aleutian Islands, seismic activity continues north through Alaska along a line that extends over the North Pole toward Svalbard.

This northward path through Alaska is illustrated by the earthquakes on the image below.


“Earthquakes are prominent along the entire border of the North American Plate”, Sam Carana adds, “but they increasingly appear to be taking this shortcut through Alaska and the underlying cause of this is melting of ice in north Canada and on Greenland”.

“This Ring Of Ice spells danger, just like the name Ring Of Fire indicates danger”, Sam Carana concludes. “The name Ring Of Fire warns about possible volcanoes, earthquakes, landslides and tsunamis. The Ring Of Ice seems even more dangerous, since seismic activity could destabilize methane hydrates contained in sediments under the Arctic Ocean, and could trigger huge methane eruptions. The fault line running from Greenland to Siberia is the most dangerous area on Earth in that respect”.

From the earlier post High Methane Levels over Laptev Sea







Friday, August 8, 2014

The Arctic Methane Monster's Rapid Rise


Researcher Jennifer Hynes recently gave a frightening presentation about the situation in the Arctic and the odds that things will rapidly spiral out of control soon, escalating into runaway global warming a few decades from now. 




Above, a slide from the presentation, warning about the danger of earthquakes causing methane hydrate destabilization (from: Smoke Blankets North America). As the map below shows, 77 M4+ earthquakes did hit locations around Greenland in the year 2014 up until August 4.


Below is Jennifer's presentation, also on youtube at youtube.com/watch?v=a9PshoYtoxo



The image below shows sea surface temperature anomalies in the Arctic at August 7, 2014.


Warm water is carried into the Arctic Ocean by the Gulf Stream, as illustrated by the image below.
[ click on image to enlarge ]
The image shows how the Gulf Stream brings warm water to the edge of the sea ice. Waters close to Svalbard reached temperatures as high as 15.6°C (60.1°F) on August 8, 2014 (green circle). Note that what the image shows are sea surface temperatures only. At greater depths (say 300 m), warm water is pushed through the Greenland Sea by the Gulf Stream. Since the passage west of Svalbard is rather shallow, a lot of this warm water comes to the surface there. The high sea surface temperatures west of Svalbard thus indicate that the Gulf Stream is carrying very warm water (warmer than 15°C) at greater depths and is pushing this underneath the sea ice north of Svalbard.

As said, the situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan blog at climateplan.blogspot.com and as illustrated by the image below.



Tuesday, June 24, 2014

Earthquakes and Warm Water threaten Arctic

[ soucre: NOAA image - click to enlarge]
A major earthquake hit the Aleutian Islands, Alaska, on June 23, 2014.

The earthquake occurred at 51.797°N 178.760°E, 15 miles (24 km) southeast of Little Sitkin Island, Alaska, at a depth of 66.8 miles (107.5km).

The U.S. Geological Survey (USGS) earlier listed the earthquake at a magnitude of 8 on the Richter scale, but eventually gave the quake a magnitude of 7.9.

Initial tsunami warnings, as reflected by the two NOAA images on the right, were later cancelled, e.g. the Pacific Tsunami Warning Center in Hawaii said the earthquake’s epicenter was too deep to pose a tsunami threat to its coasts.

Indeed, earthquakes that occur at less depth, i.e. closer to the seafloor, pose a greater tsunami threat, as more energy will enter the sea as kinetic energy pushing up wave height propelled in the form of a tsunami.

Earthquakes that occur at greater depth pose other kinds of threats. When earthquakes hit deep under the sea floor, more energy will translate into shockwaves that can propagate over great distances through the Earth crust, particularly along fault lines.

[ source: NOAA image - click to enlarge]
In this case, the situation is particularly threatening for the Arctic Ocean. As the map below shows, the fault line where this earthquake hit extends through Siberia into the Laptev Sea and was hit by three earthquakes recently:

M 4.9 - East of Severnaya Zemlya
2014-06-22 23:58:24 UTC
Location 78.520°N 125.942°E
Depth 10.00 km (6.21 mi)

M 4.7 - Laptev Sea
2014-06-01 08:52:43 UTC
Location 75.012°N 133.665°E
Depth 10.00 km (6.21 mi)

M 4.8 - 172km N of Deputatskiy, Russia
2014-05-29 05:07:33 UTC
Location 70.844°N 139.761°E
Depth 10.00 km (6.21 mi)


A cluster of earthquakes that recently hit the Aleutian Islands shows up in green in the top right corner op above map. Also note the red dot on the right, respresenting a M 4.1 earthquake that hit the Sea of Okhotsk on June 22, 2014 (at 09:47:47 UTC, location 51.843°N 151.310°E), at a depth of 527.66 km (327.87 mi).

Earthquakes are a major threat for the Arctyic as they can destabilize methane hydrates contained in sediments under the seafloor of the Arctic Ocean.

The situation is the more dangerous given the warm sea water that threatens to enter the Arctic Ocean, as illustrated by the image below.


As the recent NOAA overview of the climate situation in May 2014 describes, combined average temperature over global land and ocean surfaces reached a record high for May, at 0.74°C (1.33°F) higher than the 20th century average. Across the oceans, the global monthly-averaged sea surface temperature was 0.59°C (1.06°F) higher than the 20th century average, marking the highest May temperature on record. This is further illustrated by the image below.

Meanwhile, the situation hasn't improved, as illustrated by the image below.


The NOAA image below shows sea surface temperature anomalies in the Arctic Ocean on June 23, 2014, with many areas showing anomalies above 8 degrees Celsius.



According to NOAA's Climate Prediction Center, there is about a 70% chance that El Niño conditions will develop during the Northern Hemisphere summer 2014 and an 80% chance it will develop a few months later.

As discussed in earlier posts, the sea ice is already very thin, and while ocean heat is melting the sea ice from beneath, the sun is warming up the ice from above. At this time of year, insolation in the Arctic is at its highest, as Earth reaches its maximum axial tilt toward the sun of 23° 26'. In fact, insolation during the months June and July is higher in the Arctic than anywhere else on Earth, as discussed at this earlier post.

Feedbacks further accelerate warming in the Arctic, as described in the earlier post Feedbacks in the Arctic. Temperature rises of the water close to the seafloor of the Arctic Ocean is very dangerous, as heat penetrating sediments there could cause hydrate destabilization, resulting in huge amounts of methane entering the atmosphere over the Arctic Ocean.

In conclusion, the situation is the Arctic is threatening to escalate into runaway warming and urgently requires comprehensive and effective action as discussed at the Climate Plan blog.

Tuesday, April 1, 2014

Earthquakes in the Arctic Ocean

Earthquakes in the Arctic Ocean
indications of imminent catastrophic methane eruptions?

1. Methane over Greenland

The image below shows high methane concentrations over Greenland and over the Arctic Ocean.

[ Yellow areas indicate methane readings of 1950 ppb and higher - click on image to enlarge ]
The large yellow areas on this image indicate that the methane entered the atmosphere there. This is especially likely when such large yellow areas keep appearing in the same area over a few days. In the case of the large yellow areas around Novaya Zemlya, the methane is likely to have travelled there underneath the sea ice, from the Gakkel Ridge, to enter the atmosphere where the sea ice was thin or fractured enough for the methane to pass through, as discussed in earlier posts.

As described in the post High methane readings over Greenland, huge temperature swings can hit areas over Greenland over the course of a few days. Temperature anomalies may go down as low as as -20°C one day, then climb as high as 20°C a few days later, to hit temperature anomalies as low as -20°C again some days later.

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 wild pressure and temperature swings is causing movement and fractures in the ice, and this enables methane to rise to the surface and enter the atmosphere.

To further illustrate this, the image below shows recent temperature anomaly forecasts over Greenland.

[ click on image to enlarge ]
2. What is causing these extreme weather events?

Frigid cold weather in the U.S., torrential rain and flooding in the U.K., and wild temperature swings over Greenland. What is causing these extreme weather events? 

As discussed in many previous posts, the Arctic has become warmer than it used to be and temperatures in the Arctic are rising several times faster than global temperatures. This decreases the temperature difference between the areas to the north and to the south of the Jet Stream, which in turn decreases the speed at which the Jet Stream circumnavigates the globe, making the Jet Stream more wavier and increasing opportunities for cold air to descend from the Arctic and for warm air to enter the Arctic.

3. Did temperature swings also trigger earthquakes?

[ click on image to enlarge ]
These wild temperature swings may be causing even further damage, on top of the methane eruptions from the heights of Greenland. Look at the above map, showing earthquakes that hit the Arctic in March 2014.
Topographic map of Greenland
without the Greenland Ice Sheet.

BTW, above map doesn't show all earthquakes that occurred in the Arctic Ocean in March 2014. An earthquake with a magnitude of 4.5 on the Richter scale hit the Gakkel Ridge on March 6, 2014.

Importantly, above map shows a number of earthquakes that occurred far away from faultlines, including a M4.6 earthquake that hit Baffin Bay and a M4.5 earthquake that hit the Labrador Sea. These earthquakes are unlikely to have resulted from movement in tectonic plates. Instead, temperature swings over Greenland may have triggered these events, by causing a succession of compression and expansion swings of the Greenland ice mass, which in turn caused pressure changes that were felt in the crust surrounding the Greenland Ice Sheet.

Glaciers could be the key to make this happen. Glaciers typically move smoothly and gradually. It could be, however, that such wide temperature swings are causing glaciers to come to a halt, temporarily, causing pressure to build up over a day or so, to then suddenly start moving again with a shock. Intense cold can literally freeze a glacier in its track, to be shocked into moving again as temperatures rise abruptly by 40°C or so. This can send shockwaves through the ice sheet into the crust and trigger earthquakes in areas prone to destabilization. The same mechanism could explain the high methane concentrations over the heights of Greenland and Antarctica.

Ominously, patterns of earthquakes can be indicators of bigger earthquakes yet to come.

4. Situation looks set to get a lot worse

This situation looks set to get a lot worse. Extreme weather events and wild temperature swings look set to become more likely to occur and hit Greenland with ever greater ferocity. Earthquakes could reverberate around the Arctic Ocean and destabilize methane held in the form of free gas and hydrates in sediments underneath the Arctic Ocean.

Meanwhile, as pollution clouds from North America move (due to the Coriolis Effect) over the Atlantic Ocean, the Gulf Stream continues to warm up and carry warmer water into the Arctic Ocean, further increasing the likelihood of methane eruptions from the Arctic seafloor.


The above image shows the Gulf Stream off the coast of North America, while the image below shows how the Gulf Stream continues, carrying warmer water through the Atlantic Ocean into the Arctic Ocean.


Feedbacks, such as the demise of the Arctic's snow and ice cover, further contribute to speed up the unfolding catastrophe. Methane eruptions from the seafloor of the Arctic Ocean have become especially noticeable over the past half year. The big danger is that this will develop into runaway global warming, as discussed in the recent post Feedbacks in the Arctic.

Furthermore, as-yet-unknown feedbacks may start to kick in. As an example, submarine earthquakes and volcanoes could add nutrients into the water that feed methane-producing (methanogenic) microbes. A recent study found that expansion of such microbes could have played a large role in the end-Permian extinction, and that it was catalyzed by increased availability of nickel associated with volcanism. Authors support their hypothesis with an analysis of carbon isotopic changes leading up to the extinction, phylogenetic analysis of methanogenic archaea, and measurements of nickel concentrations in South China sediments.

5. Need for comprehensive and effective action

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




Related

- Methane Release caused by Earthquakes
http://arctic-news.blogspot.com/2013/09/methane-release-caused-by-earthquakes.html

- Seismic activity
http://arctic-news.blogspot.com/p/seismic-activity.html

- Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html





Saturday, October 5, 2013

Methane over deep waters of Arctic Ocean

The image below shows a lot of methane over deeper parts of oceans, in particular the Arctic Ocean.

[ click on image to enlarge ]
Let's zoom in and take a closer look at what's happening.

[ click on image to enlarge ]
As earlier discussed in the post Methane release caused by earthquakes, there has been a lot of seismic activity in the Aleutian Islands region all the way up into Alaska, including an earthquake with a magnitude of 7 on the Richter scale on August 30, 2013, and several more recent earthquakes with a higher magnitude than 6 on the Richter scale.

An earthquake with a magnitude of 4.6 on the Richter scale hit the Laptev Sea on September 28, 2013. Furthermore, there have been several earthquakes in Siberia, while an earthquake with a magnitude of 6.7 on the Richter scale recently hit the Sea of Okhotsk, which occurred at a depth of 359.3 miles (578.24 km). Earthquakes at such a depth can be felt at great distances from the epicenter and can destabilize methane hydrates.

The presence of methane over the deeper parts of the Arctic Ocean has been discussed in a number of post at this blog recently (see under related, below). It should serve as a warning to those who believed that all methane escaping from deep-sea hydrates would be oxidized in the water by microbes before entering the atmosphere.

The IPCC appears to still close its eyes for such scenarios. Look at this screenshot from IPCC AR5 WGI TS.3.7:

Low release this century? Well, the danger may seem low now in many places, but the situation is already very dangerous in the Arctic, where hydroxyl levels in the atmosphere are very low, where water temperatures can show huge anomalies and where seas can be very shallow and at times become super-saturated with methane, to the extent that oxygen depletion in the water prevents methane oxidation. In the case of large abrupt release, waters will soon become super-saturated with methane locally, especially in the shallow parts of the Arctic Ocean. Furthermore, low sea temperatures and the peculiarities of currents create conditions in the Arctic Ocean that are not beneficial to the kind of growth of microbes that would decompose methane in oceans elsewhere.

How much methane are we talking about? One look at the top image shows that there's a huge amount of methane over the Arctic Ocean. On October 3, 2013, a peak reading was recorded of 2283 ppb and that wasn't even the highest recent reading, as illustrated by the graph below.


Where were these large amounts of methane released? The animation below shows methane methane readings of over 1950 ppb on October 3, 2013, on the afternoon only and with readings at only four relatively low altitudes, with methane over the Arctic Ocean dominating the picture.

Saturday, September 28, 2013

Arctic Methane Monster

The Intergovernmental Panel on Climate Change (IPCC) has just released the Summary for Policymakers of Working Group I.

Sadly, the document contains little or no warning on the looming Arctic Methane Monster.

The IPCC does warn that people's emissions of carbon dioxide (CO2) must be reduced to avoid dangerous temperature rises.

The IPCC does add that "accounting for warming effects of increases in non-CO2 greenhouse gases, reductions in aerosols, or the release of greenhouse gases from permafrost will also lower the cumulative CO2 emissions for a specific warming target".

Yet, the IPCC fails to warn that huge amounts of methane, contained in sediments under the Arctic Ocean, are ready for release any time.

There are no warnings about high sea surface temperatures in the Arctic Ocean. In August 2013, sea surface temperatures of over 20°C (68°F) were recorded in some areas in the Beauford Sea and up to 18°C in the Bering Strait. Even this late in the melting season (September 28, 2013), sea surface temperatures of over 12°C are still recorded close to Svalbard (image right), in an area where methane hydrates are known to have become destabilized over the past few years. There are no warnings that, wherever the sea ice retreats, sea surface temperature anomalies are coloring the Arctic Ocean scarlet red, with temperature anomalies of over 4°C all over the place (image below). No warnings that earthquakes can destabilize hydrates that have become vulnerable due to temperature rises.

This lack of warning gives the false impression that the situation could only become dangerous until after decades of further emissions.  

Indeed, the IPCC acts as if there was a carbon budget to divide among countries, whereas the reality is that there is a huge carbon debt to our children, while the situation could become catastropic any time soon. It appears that the IPCC has been trying desperately to please those with vested interests in maintaining the status quo.


In reality, the situation calls for comprehensive and effective action, such as proposed at the ClimatePlan blog.


Related

- Just do NOT tell them the moster exists
http://arctic-news.blogspot.com/2013/10/just-do-not-tell-them-the-monster-exists.html


Sunday, September 15, 2013

Methane Release caused by Earthquakes


Methane hydrates can become destabilized due to changes in temperature or pressure, as a result of earthquakes and shockwaves accompanying them, severe storms, volcanic activity, coastal collapse and landslides. As an example, an earthquake followed by methane release was discussed in the post Sea of Okhotsk a few months back. Such events can be both primed and triggered by global warming, particularly in the Arctic, as follows:
  • As more ice melts away on Greenland and more water runs off into the sea, there is less weight on the Earth’s crust under Greenland. The crust and mantle can bounce back during a large melt, an effect that is called 'isostatic rebound'. This rebound can not only trigger earthquakes and landslides, it can also suck up the magma in the Earth’s crust to the surface and trigger volcanic eruptions.
  • The added weight of water from melting glaciers stresses the Earth’s crust underneath the sea, which can cause earthquakes. This is especially the case for coastal waters, where the impact of the water that flows into the sea is huge, not only in terms of weight, but also in terms of the currents they cause. 
  • As the permafrost melts, mountain ranges, soil and submarine sediments all become less robust. Where the permafrost previously held things together, we can now expect more coastal collapse, avalanches and landslides, which can send shockwaves through the sea that in turn trigger earthquakes and hydrate destabilization.
  • Methane hydrates that are on the edge of stabilization can be disturbed by global warming in two additional ways, temperature and pressure: Warming of the Earth's crust as heat penetrates sediments on the seafloor. Thermal expansion of the Earth's crust means that the crust will expand slightly in volume, resulting in expansion of the cavity that holds the hydrates. 
  • Finally, there's the additional impact of methane itself. Permafrost previously kept methane stable in sediments. Methane converting from hydrates into free gas will expand some 160 times in volume; this explosive process can trigger further destabilization. Once released into the atmosphere, the methane has a huge local warming potential, adding to the threat that further methane releases will occur locally.   


Back in 2006, Bill McGuire said: "A particular worry is that this in turn will contribute to large-scale releases of methane gas from the solid gas hydrate deposits that are trapped in marine sediments. Gas hydrates have been identified around the margins of all the ocean basins, and outbursts of gas may occur as sea temperatures climb or as rising sea levels trigger underwater quakes in the vicinity."

For more than a decade, Malcolm Light, contributor to the Arctic-news blog, has been warning about the danger of methane hydrate destabilization due to earthquakes (see the poster at the bottom of the page on seismic activity).

With this in mind, let's take a look at the most recent picture of Earth.

September 13, 2013, 3am - Sep 14, 2013 1am    [ click on image to enlarge ]

The large number of yellow spots in the top left corner are related to the flooding in the Basin of the Amur River (Heilong Jiang). Such extreme weather events are becoming ever more prominent, due to global warming and the feedbacks such as methane releases. Similarly, extreme weather events such as droughts and heatwaves lead to wildfires that also produce large amounts of methane.

The image only shows the Northern Hemisphere, but on the Southern Hemisphere, high levels of methane have been recorded for a long time on Antarctica. While huge amounts of snow fall on Antartica, the amount of snow and ice that melts each year is even larger, widening the difference between the weight the snow and ice exercize between periods. This difference in weight could similarly cause rebounds of the Earth's crust, sucking up the magma and causing methane hydrates to be destabilized, as described in the earlier post Antarctic methane peaks at 2249 ppb.

The image also shows fault lines. Several yellow spots are present on the fault line over the Arctic, including some that point at the coast of Norway; they appear to be caused by seismic activity along the fault line, as discussed in the recent post Methane reaches 2571 ppb.

Meanwhile, methane readings peaked at 2416 ppb on September 14, 2013. Very worrying are also the high methane readings close to the Gakkel Ridge, the fault line at the center of the Arctic Ocean, and the spots closer to the Laptev Sea.

Finally, there are high readings along the Aleutian Islands, Alaska. The islands, with their 57 volcanoes, are in the northern part of the Pacific Ring of Fire and they have experienced a lot of seismic activity lately, including an earthquake with a magnitude of 7 on the Richter scale on August 30, 2013, and several more recent earthquakes with a higher magnitude than 6 on the Richter scale.

[Editor: The images below, added September 24 and 26, 2013, show high methane releases at a spot just north of Greenland that was hit by an earthquake with a magnitude of 4.5 on the Richter scale on September 1, 2013, as also discussed in the post Methane reaches 2571 ppb. The two bottom images also show the magnitude 5 earthquake that hit Russia on September 24, 2013.]

September 20, 2013, 11am - Sep 22, 2013 3pm    [ click on image to enlarge ]

Sept. 25, 2013 am - the orange spot just north of Greenland indicates a recent earthquake [ click on image to enlarge ]

Map specifying details of two recent earthquakes. Size of spots indicating earthquakes on the map is relative. [ click image to enlarge ]

References and related posts

- Climate Change: Tearing the Earth Apart, by Bill McGuire (2006)

- Seismic activity, by Malcolm Light and Sam Carana (2011)
Arctic-news.blogspot.com/p/seismic-activity.html

- Thermal expansion of the Earth's crust necessitates geoengineering (2011)
Arctic-news.blogspot.com/p/thermal-expansion.html

- Runaway Warming (2011)
Arctic-news.blogspot.com/p/runaway-warming.html

- Methane reaches 2571 ppb (2013)

- Sea of Okhotsk (2013)

- Is Global Warming breaking up the Integrity of the Permafrost? (2013)

- Antarctic methane peaks at 2249 ppb (2013)

Thursday, November 15, 2012

Did Sandy trigger major earthquakes off Vancouver?

The NASA image below gives an impression of the strength of hurricane Sandy, as it approached the U.S. coast on October 28, 2012. 

Image produced with data from a radar scatterometer on the Indian Space Research Organization’s (ISRO) Oceansat-2,
showing the strength and direction of Sandy’s ocean surface winds on October 28, 2012.

This animation was created by Alex Hutko, a seismologist at the Incorporated Research Institutions for Seismology (IRIS) in Seattle. It shows how seismic stations lit up as hurricane Sandy continued its path.

The images below are screenshots from the animation, showing how three eathquakes hit the coast off British Columbia in Canada, coinciding with large tremors caused by Sandy. A 7.7 magnitude earthquake (image below) hit the coast off Vancouver on October 28, 2012, at around 2:00 EDT. The USGS later upgraded the earthuake to magnitude 7.8 and gave the time as 3:04 UTC.
 
 
A 6.3 earthquake below hit the area the same day (October 28, 2012) at 17:00 EDT (USGS: 18:54 UTC).
 
 
A 6.2 earthquake (image below) followed on October 30, 2012.
 
 
The USGS image below gives further time and location details of these earthquakes using UTC time. 
 
 
There were more earthquakes than that. At the USGS site, I counted 90 further earthquakes in the area with a magnitude of at least 4 that occurred within days of the first earthquake.
 
Paul Beckwith, regular contributor to this blog, gives the following comments on the question whether Sandy was the trigger for major earthquakes off Vancouver.
“Sandy was a massive storm, packing an enormous amount of energy. According to Jeff Master's Wunderground blog, she carried the energy equivalent of five Hiroshima sized nuclear bombs.
 
As she approached the eastern seaboard of the United States she was detected on the seismic stations in the U.S. As she moved her large size (tropical storm winds within a 900 mile diameter) and extremely low pressure center (940 mb usually indicative of Category 3 or even 4 magnitude hurricanes), she sucked enormous quantities of ocean water upward.
 
Clearly, this adds tremendous stresses onto the earths crust and pushes it downward; this was reflected in the seismic stations. The animation of her progress shows the ground stresses across North America between October 14th and November 1st. On her northward jaunt up the eastern coast the seismic strain lit up to a peak and there was a 7.8 magnitude earthquake (Oct 28th, 3:04 UTC) off Vancouver, as shown in the first image.
 
As she continued northward and just before her extremely unusual left turn (due to extreme waviness of Rossby wave jet streams leading to continental low and northward tilted blocking high), there was another maximum of red seismic activity and a 6.3 magnitude aftershock (October 28, 18:54 UTC).
 
Then she turned left and as she crossed the coastline just south of NYC there was a second large aftershock of 6.2 magnitude (October 30, 2:38 UTC). Again, this aftershock coincided with large seismic activity indicated in red on the east coast.
 
Coincidence? I think not. Stress on one side of a continental plate (North American plate in this case) can deflect the plate downward locally and cause it to bow up or down afar, i.e. on the other side of the plate of the west coast). The precise coincidence of the timing for the main quake and the 2 aftershocks with peaks of seismic activity on the eastern coast seems to match too closely to be a mere coincidence, but more study is required.”

In conclusion, there is a danger that storms and cyclones trigger submarine earthquakes, which can in turn cause shockwaves and landslides over a wide area, destabilizing hydrates and triggering massive releases of methane in the process. As the sea ice disappears, the Arctic Ocean increasingly features open waters which are more prone to cyclones.