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.

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.

Has the descent begun?

On March 9, 2014, Arctic sea ice area was at a record low for the time of the year, at only 12.88731 square kilometers.

Sea ice extent shows a similar descent, as illustrated by the NSIDC image below.

NSIDC update: The image below shows that Arctic sea ice extent was 14.583 square kilometers on March 11, 2014 (light green line), a record low for this time of the year and smaller than it was in 2006 (magenta line) and 2011 (orange line) at this time of the year.

The situation is dire, given that methane concentrations have risen strongly following an earthquake that hit the Gakkel Ridge on March 6, 2014, as illustrated by the image below.

[ click on image to enlarge ]

Huge amounts of methane have been released from the seafloor of the Arctic Ocean over the past half year, and the resulting high methane concentrations over the Arctic will contribute to local temperature rises.

The image below shows that sea surface temperatures are anomalously high in the Arctic Ocean and off the east coast of North America, from where warm water is carried by the Gulf Stream into the Arctic Ocean.

The prospect of an El Niño event makes the situation even more dire. NOAA recently issued an El Niño Watch. This follows a conclusion by an international research team that found a 75% likelyhood of an El Niño event in late 2014.

The consequences of sea ice collapse would 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 is unacceptable and calls for comprehensive and effective action as discussed at the Climate Plan blog.

M4.5 Earthquake hits Gakkel Ridge

The above image shows recent large methane release over the Gakkel Ridge, the faultline that crosses the Arctic Ocean between the northern tip of Greenland and the Laptev Sea (red line on map). Methane readings were as high as 2395 ppb at 586 mb, an altitude that often shows high methane readings originating from the Arctic Ocean.

An earthquake with a magnitude of 4.5 hit the Gakkel Ridge at a depth of 2 km on March 6, 2014, at 11:17.17.0 UTC. The location is shown on the map below.

[ click on image to enlarge ]

The image below shows more recent methane readings, around March 8, 2014.

The image below is a Naval Research Laboratory forecast of sea ice thickness for March 8, 2014, run on March 3, 2014.

Meanwhile, the sea ice is close to record lows (for the time of the year), as illustrated by the images below. The image directly below shows sea ice area.

The image below shows sea ice extent.

The image below, by Wipneus, shows sea ice volume.

The image below, by Andy Lee Robinson, offers a different way of looking at sea ice volume, the Arctic Death Spiral.

Norwegian Sea hit by 4.6M Earthquake

In the early morning of November 9, 2013, the Norwegian Sea was hit by an earthquake with a magnitude of 4.6 on the Richter Scale. Earlier (on October 28, 2013), an earthquake with a 5.3 magnitude hit the Greenland Sea closer to Svalbard.

These earthquakes come at a time when huge amounts of methane are rising from the seabed of the Arctic Ocean, from areas on or close to the fault line that crosses the Arctic Ocean. The location of the earthquake that hit the Norwegian Sea is indicated on the map below with a white circle.

[ click on image to enlarge ]

Related

- Greenland Sea hit by M5.3 Earthquake
http://arctic-news.blogspot.com/2013/10/greenland-sea-hit-by-m53-earthquake.html

- Methane, Faults and Sea Ice
http://arctic-news.blogspot.com/2013/11/methane-faults-and-sea-ice.html

- Earthquake hits waters off Japan
http://arctic-news.blogspot.com/2013/10/earthquake-hits-waters-off-japan.html

- Earthquake hits Laptev Sea
http://arctic-news.blogspot.com/2013/09/earthquake-hits-laptev-sea.html

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

- Earthquake M6.7 hits Sea of Okhotsk
http://methane-hydrates.blogspot.com/2013/10/earthquake-m67-hits-sea-of-okhotsk.html

- Sea of Okhotsk
http://methane-hydrates.blogspot.com/2013/06/sea-of-okhotsk.html

Post by Sam Carana.

Greenland Sea hit by M5.3 Earthquake

An earthquake with a magnitude of 5.3 on the Richter scale hit the Greenland Sea near Svalbard on October 28, 2013.

[ Earthquake indicated by orange dot - click on image to enlarge ]

For a long time, huge sea surface temperature anomalies have shown up in the area where the earthquake hit. The image below compares the situation before and after the earthquake hit.

[ click on image to enlarge ]

These huge sea surface temperature anomalies were discussed before, in the September 19, 2013, post Is the North Pole now ice-free?

This post mentions that sea surface temperatures in some spots close to Svalbard are far higher than even in the waters closer to the Atlantic Ocean. In some of these spots, sea surface temperatures are well over 10°C (50°F).

The post continues: Where does this heat come from? These hot spots could be caused by undersea volcanic activity; this is the more dangerous as this area has seen methane bubbling up from destabilized hydrates before; the dangers of this situation have been discussed repeatedly, e.g. in the April 2011 post Runaway Global Warming.

Indeed, the big danger is large abrupt release of methane from destabilized hydrates. At the moment, the amount of methane entering the atmosphere over the Arctic Ocean is already huge, as illustrated by the image below that shows high methane readings over the past few days.

[ click on image to enlarge ]

We'll keep monitoring the situation.

Earthquake hits waters off Japan

An earthquake with a magnitude of 7.3 on the Richter scale hit the waters 231 miles (371 kilometers) east of Japan on October 25, 2013, reports rt.com, adding that the quake prompted an evacuation at the devastated Fukushima Daiichi plant and that strong tremors could be felt on Japan’s main Honshu Island, as well as on the northern island of Hokkaido.

USGS.gov reported the quake as having a magnitude of 7.1 followed up by several smaller quakes, as indicated on the image below, which also indicates the location of Fukushima.

[ click to enlarge ]

The image below shows that methane readings of 1950+ were recorded on and around the location where the earthquake hit. The image merely shows methane that did enter the atmosphere. More methane will have escaped from the seabed, but much of it will have oxidized in the water.

The occurence of this earthquake is very worrying, due to the situation at the Fukushima Daiichi nuclear plant. It is also relevant to the situation in the Laptev Sea, north of Siberia, for a number of reasons, including: 

1. As the above image clearly shows, earthquakes can trigger methane releases from the seabed, as previously discussed in the post Methane Release caused by Earthquakes.
2. Global warming is contributing to the occurance of earthquakes. For years, geophysical hazard specialist Bill McGuire has studied this impact of global warming, in particular the Earth's crust bouncing and bending in response to the melting of the great ice sheets and the filling of the ocean basins—dramatic geophysical events that triggered earthquakes, spawned tsunamis, and provoked a series of eruptions from the world's volcanoes. Bill McGuire warns that staggering volumes of melt water poured into the ocean basins, warping and bending the crust around their margins. The resulting tossing and turning provoked a huge resurgence in volcanic activity, seismic shocks, and monstrous landslides—the last both above the waves and below.
   
   According to calculations posted by Doyle Doss in January 2012, the increase in weight of the Pacific Ocean over the last 50 years due to freshly introduced water from land ice melt is 10 Trillion 331 Billion 125 Million 200 Thousand TONS. In conclusion, global warming is making methane releases triggered by seismic activity worse. 
3. The fault lines around Japan are interconnected with other fault lines, as illustrated by the image below, from the post High Methane Levels over Laptev Sea, showing methane readings on October 20, 2013 pm. Earthquakes can trigger further earthquakes, especially along the same or interconnected fault lines. 

The image below shows methane readings on October 25, 2013 pm, indicating that high methane readings continue to be recorded over the Laptev Sea.

[ click to enlarge ]

The above image also shows that the Laptev Sea was hit by an earthquake with a magnitude of 4.6 on the Richter scale on September 28, 2013. Earlier, on August 7 and on September 9, earthquakes with similar magnitudes had hit the Laptev Sea closer to land, as described in the post Earthquake hits Laptev Sea.

For more than a month, large amounts of methane have been present over the Arctic Ocean, in particular over the Gakkel Ridge and, more recently, also over the Laptev Rift.

Sediments under the Arctic Ocean contain huge amounts of methane in the form of hydrates and free gas. Some areas, such as the Gakkel Ridge and the Laptev Rift are prone to earthquakes, volcanoes and landslides, as they are part of a tectonic fault line that crosses the Arctic Ocean.

The danger is that, as the permafrost retreats and the snow and ice cover declines rapidly, methane in the Arctic is on the brink of being released abruptly and in large quantities from the seabed. A single earthquake, perhaps even outside of the Arctic Ocean could set this off. There are many more factors that influence seismic activity, such as the position of sun, moon and stars, and the depth at which seismic activity occurs, as tremors can be felt far away from earthquakes that occur at greater depth. Anyway, the danger is that earthquakes will trigger abrupt release of methane from the seabed of the Arctic Ocean, and since methane is a powerful greenhouse gas, such a release could further accelerate local warming, triggering further destabilization of methane in the seabed, escalating into abrupt climate change across the globe.

The depth of the seabed is also important in this regard, since shallow seas can warm up rapidly, while methane that escapes from the seabed has less chance to get oxidized in shallow seas. Large parts of the Arctic Ocean are very shallow, in particular the Laptev Sea, as further descibed in the post methane hydrates.

Earthquake hits Laptev Sea

An earthquake with a magnitude of 4.6 on the Richter scale hit the Laptev Sea on September 28, 2013.

[ click on image to enlarge ]

This follows a number of earthquakes on or close to the fault line that crosses the Arctic Ocean and extends into Siberia, as shown on above map and on the map below.

[ click to enlarge ]

Furthermore, 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.

This is a lot of seismic activity for the Arctic, given that this is a relatively quiet part of the globe in terms of earthquakes.

[ click on image to enlarge ]

As above map shows, there were 1250 earthquakes with a magnitude of 2.5 or higher over the past 30 days globally. About 90% of the world's earthquakes occur along the Ring of Fire, on the edges of the Pacific Ocean.

The fault line that crosses the Arctic Ocean marks the boundery between the North American Plate and the Eurasian Plate. Along this fault, huge amounts of methane are held in sediments, in the form of free gas and hydrates. The danger is that earthquakes along this fault will destabilize methane, causing it to rise abruptly in large amounts and enter the atmosphere.

As the top image shows, a lot of methane is currently present in the atmosphere along this fault line. Methane has shown up there repeatedly, indicating that methane there has been prone to release for some time and warning that even larger releases could occur soon.

Related posts

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

- North Hole (2013)

http://arctic-news.blogspot.com/2013/09/north-hole.html

- Sea of Okhotsk (2013)
Methane-hydrates.blogspot.com/2013/06/sea-of-okhotsk.html

- 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

Post by Sam Carana.

Methane reaches 2571 ppb

Methane as recorded by IASI* reached levels of up to 2571 parts per billion (ppb) on September 11, 2013.

The image below shows the peak levels that have been reached recently, as well as the highest mean methane level for each day.

Where did the methane come from?

IASI data do not identify locations, other than that all locations where methane is present in concentrations higher than 1950 ppb show up in yellow.

Yet, there are some ways to further examine where these high levels came from. To create the top image, only four layers were selected. The yellow spots on the image show locations where methane is present at the selected layers (695-766 mb) at concentrations of 1950 ppb and higher. At these relatively low altitudes, yellow spots will show up at fewer locations than at some of the higher altitudes, yet one can assume that the largest sources will be included among those showing up; and indeed, peak methane levels at these altitudes ranged from 2193 ppb to 2328 ppb, which are extremely high levels.

On the top image, there are several locations that look suspicious, including a large spot north of the New Siberian Islands, while the Kara Sea and the Barents Sea, and many locations around Greenland all feature suspicious yellow spots.

Most worrying are the numerous spots clustered off the coast of Norway, which show up quite prominently at many altitudes. The situation is reminiscent of the Storegga Slides, the underwater landslides that occurred at the edge of Norway's continental shelf thousands of years ago. The latest incident occurred some 8,000 years ago.

Seismic Activity

Earthquakes can cause tremors over long distances, especially along fault lines.

There has been some seismic activity close to Greenland that could have triggered one or more landslides off the cost of Norway, since the fault line points that way. An earthquake with a magnitude of 4.5 on the Richter scale occurred occured on September 1, 2013, 08:49:19 UTC, at a location 214km NE of Nord, Greenland, as illustrated by above image and the image below.

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* IASI (Infrared Atmospheric Sounding Interferometer) is a hyperspectral infrared sounder residing on the European Space Agencys (ESA) MetOp series of polar orbiting satellites.