Monday, November 9, 2015

Ocean Heat

Sea Surface Temperatures

Sea surface temperatures were as high as 15.8°C or 60.4°F near Svalbard on November 7, 2015, a 13.7°C or 24.7°F anomaly. Let this sink in for a moment. The water used to be close to freezing point near Svalbard around this time of year, and the water now is warmer by as much as 13.7°C or 24.7°F.

[ click on image to enlarge ]
Above image further shows that sea surface temperature anomalies as high as 6.7°C or 12.1°F were recorded on November 7, 2015, off the coast of North America, while anomalies as high as 6°C or 10.9°F were recorded in the Bering Strait.

NOAA analysis shows that the global sea surface in September 2015 was the warmest on record, at 0.81°C (1.46°F) above the 20th century average of 16.2°C (61.1°F). On the Northern Hemisphere, the anomaly was 1.07°C (1.93°F).

[ click on image to enlarge ]

How did temperatures get so high near Svalbard? The answer is that ocean currents are moving warm water from the Atlantic Ocean into the Arctic Ocean. The ocean is warmer underneath the sea surface and at that location near Svalbard warm water from below the surface emerges at the surface.

Ocean Heat

The oceans are warming up rapidly, especially the waters below the sea surface. Of all the excess heat resulting from people's emissions, 93.4% goes into oceans. Accordingly, the temperature of oceans has risen substantially over the years and - without action - the situation only looks set to get worse.

NOAA's ocean heat content figures for 0-2000 m are very worrying, as illustrated by the image below.


The image below was created with data for January through to March, while adding non-linear trendlines for ocean heat at depths of 0-700 m and 0-2000 m.

[ click on image to enlarge ]
Growth of ocean heat content for 0-700 m appears to follow a polynomial trend, and growth of ocean heat content for 0-2000 m appears to be rising even more strongly, following an exponential trend.

The danger is that, as ocean heat continues to grow, ocean currents will keep carrying ever warmer water from the Atlantic and Pacific Oceans into the Arctic Ocean.

Merely watching temperatures at the surface of the ocean may underestimate the warming that is taking place below the sea surface. At the sea surface, evaporation takes place that cools the water. Furthermore, melting of sea ice and glaciers will make that a layer of cold freshwater spreads at the surface, preventing much transfer of heat from the ocean to the atmosphere, as discussed at this earlier post. The blue-colored areas on the Northern Hemisphere on the top image are partly the result of this meltwater. There is another reason why these areas are relatively cool, i.e. sulfates, as further discussed in the section below.

Aerosols

Particulates, in particular sulfate, can provide short-term cooling of the sea surface. Large amounts of sulfate are emitted from industrial areas in the east of North America and in East Asia. On the Northern Hemisphere, the Coriolis effect makes that such emissions will typically reach areas over the nearby ocean to the east of such industrial areas, resulting in the sea surface there being cooled substantially, until the particulates have fallen out of the sky. Since the sulfate is emitted on an ongoing basis, the cooling effect continues without much interruption.

[ click on image to enlarge ]
This sulfate has a cooling effect on areas of the sea surface where ocean currents are moving warm water toward the Arctic Ocean. Because the sea surface gets colder, there is less evaporation, and thus less heat transfer from the ocean to the atmosphere during the time it takes for the water to reach the Arctic Ocean. As a result, water below the sea surface remains warmer as it moves toward the Arctic Ocean.


Similarly, as illustrated by above image, sulfur dioxide emitted in industrial areas in North America and East Asia can extend over the oceans, cooling the surface water of currents that are moving water toward the Arctic Ocean.

Methane

The image below shows that atmospheric methane levels in 2014 were 1833 parts per billion (WMO data) or 254% the pre-industrial level. WMO data are for 1984-2014 and are marked in red, while IPCC data (AR5) are for the years 1755-2011 and are marked in blue.



The image below shows the rise of methane levels from 1984 created with World Metereological Organization (WMO) data. The square marks a high mean 2015 level, from NOAA's MetOp-2 satellite images, and it is added for comparison, so it does not influence the trendline, yet it does illustrate the direction of rise of methane levels and the threat that global mean methane levels will double well before the year 2040.


The image below illustrates the danger that large amounts of methane will erupt from the Arctic Ocean, particularly in East Siberian Arctic Shelf, where the sea is quite shallow, so much of the methane can reach the atmosphere without being broken down by microbes on the way up through the water column.


The Threat

Ocean heat threatens to increasingly reach the seafloor of the Arctic Ocean and unleash huge methane eruptions from destabilizing clathrates. Such large methane eruptions will then warm the atmosphere at first in hotspots over the Arctic and eventually around the globe, while also causing huge temperature swings and extreme weather events, contributing to increasing depletion of fresh water and food supply, as further illustrated by the image below, from an earlier post.

[ click on image at original post to enlarge ]

Climate Plan

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

Below is a radio version of this post, read by Debba Kale Earnshaw at this episode of extinctionradio.org


Sea surface temperatures were as high as 15.8°C or 60.4°F near Svalbard on November 7, 2015, a 13.7°C or 24.7°F anomaly....
Posted by Sam Carana on Monday, November 9, 2015

Friday, October 30, 2015

Methane Vent Hole In Arctic Sea Ice?

Methane vent hole in the ice?

In October 2015, an area appeared in the Arctic sea ice where the temperature of the ice was a few degrees Celsius higher and where ice concentration and salinity levels were substantially lower than the surrounding ice. The image below pictures the situation on October 11, 2015.

[ click on image to enlarge ]
Could this have been an iceberg? If so, ice concentration should have been higher, rather than lower. More likely is that this is a vent hole with methane rising through cracks in the sea ice.

Malcolm Light comments: "The whole of the Arctic seabed is covered with methane hydrates and NASA satellites should have long ago defined where the major plumes were coming out. It is clearly a surface methane vent hole in the ocean ice analogous to the large methane vent holes that appeared all over northern Siberia this year. It means we have overheated the Arctic seafloor to the extent where the methane hydrates are now unstable and we could have further major releases at any time. We have already lit the fuse on a giant methane subsea permafrost bomb in the Arctic which can go off at any moment."

Roger Caldwell responds: "I think it's upwelling warm water. There is a ridge right below the spot. I can see warm spots through the ice on the nullschool program. The warm water comes through the Bering Strait and sinks to the mid levels. When it gets to the ridge it flows upward, making a temporary polynya."

The image below shows warm water entering the Arctic Ocean from the Pacific Ocean (through the Bering Strait) and the Atlantic Ocean, with the dark-red color of many areas in the Arctic Ocean indicating warm waters, including an area close to the North Pole marked by the red circle. So, the spot could indeed be a polynya caused by upwelling of warm water. Alternatively to the Pacific Ocean, the warm water could have originated from the Atlantic Ocean. In the Fram Strait, near Svalbard, sea surface temperatures as high as 11.9°C or 53.5°F were recorded on October 28, 2015, i.e. 9.6°C or 17.2°F warmer than 1981-2011 (at the location marked by the green circle).

[ click on image to enlarge ]
Of course, with water this warm reaching the center of the Arctic Ocean, the threat that this will cause (further) destabilization of methane hydrates at the seafloor of the Arctic Ocean is equally ominous. The more recent image below shows warm waters in the Arctic Ocean in a different way, partly because the anomaly is calculated from the period 1961 to 1990.


The image below shows that sea surface temperatures as high as 12°C or 53.5°F were recorded near Svalbard on October 31, 2015, i.e. 9.7°C or 17.4°F warmer than 1981-2011 (at the location marked by the green circle).

[ click on image to enlarge ]
On the image below, Malcolm Light added the Gakkel Ridge, i.e. the fault line that extends on the seafloor of the Arctic Ocean from the northern tip of Greenland to Siberia (red line), and the location of explosive volcanoes (lilac spot), with content from Sohn et al., 2008.

A zone of increased heat near the North Pole which may be related to large quantities of gas released from a group of extremely pyroclastic carbon dioxide-rich volcanoes located at the Gakkel Ridge 
The table below shows the height that emerging carbon dioxide plumes can be expected to reach for a given carbon dioxide volume fraction in the foam at the top of a magma chamber.

Malcolm Light adds:
"Sohn et al. (2007) outlined how the sequence of extreme pyroclastic eruptions occur along the Gakkel Ridge (85°E volcanoes) at an ultra-slow plate spreading rate (<15-20 mm/year). These volcanoes formed from the explosive eruption of gas-rich magmatic foams. Long intervals between eruptions with slow spreading caused huge gas (volatile) build up high storage pressures, deep in the crust. 

Extension of the 85°E seismic swarm occurred over 3 months but later earthquakes were caused by large implosions from the explosive discharge of pressurized magmatic foam from a deep-lying magma chamber through the fractured chamber roof which rapidly accelerated vertically, expanded and decompressed. There were many periods of widespread explosive gas discharge from 1999 over two years detected by small-magnitude sound signals from seismic networks on the ice. 

Pyroclastic rocks contain bubble wall fragments and were widely distributed over an area of more than 10 square km. Deep fragmentation was caused by the accumulation of a gas (volatile) foam within the magma chamber which then fractured, formed a pyroclastic fountain 1-2 km high in the Arctic Ocean and spread the pyroclastic material over a region whose size was proportional to the depth of the magma chamber (see above table). A volatile carbon dioxide content of 14% (Wt./Wt. - volume fraction 75%) is necessary at 4 km depth in the Arctic Ocean to fragment the erupting magma." 

As said, with water this warm reaching the center of the Arctic Ocean from the Atlantic and Pacific Oceans, the threat is that added heat from volcanic activity or pressure shocks from underwater earthquakes or landslides will trigger (further) destabilization of methane hydrates at the seafloor of the Arctic Ocean.

Below follows some more background.

Animations

Naval Research Laboratory 30-day animations are added below for temperature, concentration, salinity and thickness of the sea ice. Click on each of them to view full versions.

Temperature
Concentration

Salinity

Thickness

[ click on animations to enlarge ]

Background on tectonic plates and faults

A major fault line crosses the Arctic Ocean, forming the boundary between two tectonic plates, the North American Plate and the Eurasian Plate. These plates slowly diverge, creating seismic tension along the fault line. From where the Mid-Atlantic ridge enters the Arctic Ocean, it is called the Gakkel Ridge. The fault continues as the Laptev Sea Rift, on to a transitional deformation zone in the Chersky Range in Siberia, then the Ulakhan Fault between the North American Plate and the Okhotsk Plate, and then continues as the Aleutian Trench to the end of the Queen Charlotte Fault system.



The situation in October 2013

High methane readings were recorded for a period of just over one day, October 19 - 20, 2013, as shown in the images below. Indicated in yellow are all methane readings of 1950 ppb and over.


To pointpoint more closely where methane is venting along the Laptev Sea Rift, the image below gives readings for October 20, 2013, pm, at just three altitudes (607 - 650 mb).


Satellite measurements recorded methane readings of up to 2411 ppb on October 20, 2013.

Methane venting in the Laptev Sea in 2005 and 2007

For further reference, large amounts of methane have been venting in the Laptev Sea area in previous years. Added below is an edited part of a previous post, Unfolding Climate Catastrophe.

In September 2005, extremely high concentrations of methane (over 8000 ppb, see image on the right) were measured in the atmospheric layer above the sea surface of the East Siberian Shelf, along with anomalously high concentrations of dissolved methane in the water column (up to 560 nM, or 12000% of super saturation).

The authors conclude: "Since the area of geological disjunctives (fault zones, tectonically and seismically active areas) within the Siberian Arctic shelf composes not less than 1-2% of the total area and area of open taliks (area of melt through permafrost), acting as a pathway for methane escape within the Siberian Arctic shelf reaches up to 5-10% of the total area, we consider release of up to 50 Gt of predicted amount of hydrate storage as highly possible for abrupt release at any time".

In 2007, concentrations of dissolved methane in the water column reached a level of over 5141 nM at a location in the Laptev Sea. For more background, see the previous post, Unfolding Climate Catastrophe.

Methane levels in October 2015

The image below shows high methane concentrations over the Arctic Ocean on October 11, 2015, pm, at 840 mb, i.e. relatively close to sea level.


The image below shows high levels of methane over the Arctic Ocean at higher altitude (469 mb) on October 28, 2015, pm, when methane levels were as high as 2345 ppb. 


Note that the above two images have different scales. The data are from different satellites. The video below shows images from the MetOp-2 satellite, October 31, 2015, p.m., at altitudes from 3,483 to 34,759 ft or about 1 to 11 km (241 - 892 mb).


Peak methane levels were as high as 2450 ppb on November 1, 2015.

Update: Warm Water in Arctic Ocean

On November 5, 2015, sea surface temperatures as high as 8.5°C or 47.3°F showed up in the Bering Strait, an anomaly of 6.6°C or 11.9°F, while sea surface temperatures as high as 14.4°C or 57.9°F showed up near Svalbard on November 5, 2015, a 12.2°C or 22°F anomaly. The situation is illustrated by the image below.

[ click on image to enlarge ]
These high temperatures indicate that the sea can be a lot warmer below the surface than at the surface, and it appears that very warm waters are continuing to enter the Arctic Ocean from both the Pacific Ocean and the Atlantic Ocean. As discussed in previous posts such as this one, the danger is that ever warmer waters will (further) destabilize methane hydrates at the seafloor of the Arctic Ocean, resulting in abrupt methane eruptions that could dwarf the impact of existing greenhouse gases in the atmosphere.

Climate Plan

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


Links

- Explosive volcanism on the ultraslow-spreading Gakkel ridge, Arctic Ocean, Sohn et al. (2007, published 2008)
http://www.nature.com/nature/journal/v453/n7199/full/nature07075.html

- Unfolding Methane Catastrophe
http://arctic-news.blogspot.com/2013/10/unfolding-methane-catastrophe.html

- Further Confirmation of a Probable Arctic Sea Ice Loss by Late 2015, by Malcolm P.R. Light (Sep. 1, 2012)
http://arctic-news.blogspot.com/2012/09/further-confirmation-of-a-probable-arctic-sea-ice-loss-by-late-2015-loss.html

In October 2015, an area appeared in the Arctic sea ice where the temperature of the ice was a few degrees Celsius...
Posted by Sam Carana on Friday, October 30, 2015

Friday, October 23, 2015

September 2015 Sea Surface Warmest On Record

Arctic Sea Ice Extent Growth Seals Off Arctic Ocean



Arctic sea ice increased rapidly in October 2015, after reaching its annual minimum in September. As the image below shows, the growing sea ice extent has effectively sealed off the Arctic Ocean from the atmosphere, resulting in less evaporation and heat transfer from the ocean to the atmosphere.

The Naval Research Laboratory 30-days animation (up to October 22, with forecast added up to October 30) on the right shows that sea ice has grown in extent, adding plenty of very thin sea ice, while the existing ice has hardly increased its thickness.

The Buffer Has Gone

Thick sea ice used to extend meters below the sea surface in the Arctic, where it could consume massive amounts of ocean heat through melting this ice into water. As such, thick sea ice acted as a buffer. Over the years, Arctic sea ice thickness has declined most dramatically. This means that the buffer that used to consume massive amounts of ocean heat carried by sea currents into the Arctic Ocean, has now largely gone.

Latent heat loss, feedback #14 on the Feedbacks page
Cold Freshwater Lid on North Atlantic

Meanwhile, especially from 2012, huge amounts of freshwater have run off Greenland, with the accumulated freshwater now covering a huge part of the North Atlantic, acting as a lid that prevents ocean heat to evaporate from the North Atlantic.


Since it's freshwater that is now covering a large part of the surface of the North Atlantic, it will not easily sink in the very salty water that was already there. The water in the North Atlantic was very salty due to the high evaporation, which was in turn due to high temperatures and strong winds and currents. Freshwater tends to stay on top of more salty water, even though the temperature of the freshwater is low, which makes this water more dense. The result of this stratification is less evaporation in the North Atlantic, and less transfer of ocean heat to the atmosphere, and thus lower air temperatures than would have been the case without this colder surface water.

Cold freshwater lid on North Atlantic, feedback #28 on the Feedbacks page
The cold lid over the North Atlantic has meanwhile expanded. Greenland has been experiencing wild weather swings this month, with temperatures shifting from one extreme end of the scale to the other end. The image below shows temperature anomalies on October 17 (left panel), October 23 (center panel) and a forecast for October 30 (right panel). Temperatures are forecast to swing back to the extreme high end of the scale, pushing up temperature anomalies for the Arctic as a whole to as high as 2.37°C on October 30, 2015.

Wild weather swings causing methane releases, feedback #21 on the Feedbacks page
These wild weather swings over Greenland threaten to cause cracks in the ice, with methane hydrates in the ice becoming destabilized, resulting in releases of huge amounts of methane from hydrates and free gas into the atmosphere, as earlier discussed as feedback #21 on the Feedbacks page.

Strong winds have further contributed to extend the cold lid over the North Atlantic, while also making cold air flow from Greenland over the North Atlantic. This is illustrated by the image below, depicting the situation on October 23, 2015, with the left panel showing surface wind speed, while the right panel shows the resulting sea surface temperature anomalies. 


The video below shows surface wind speed forecasts in the Arctic from October 25 to November 1, 2015.



Ocean Temperature Rise

NOAA analysis shows that the global sea surface in September 2015 was the warmest on record, at 0.81°C (1.46°F) above the 20th century average of 16.2°C (61.1°F). On the Northern Hemisphere, the anomaly was 1.07°C (1.93°F).

[ click on image to enlarge ]
Of all the excess heat resulting from people's emissions, 93.4% goes into oceans. Accordingly, the temperature of oceans has risen substantially over the years and - without action - the situation only looks set to get worse.

The Threat

As ocean temperatures continue to rise, especially in the North Atlantic, the Gulf Stream will keep carrying ever warmer water from the North Atlantic into the Arctic Ocean. Without the buffer of thick sea ice to consume the increasing amount of ocean heat, the threat is that ocean heat will increasingly reach the seafloor and unleash huge methane eruptions from destabilizing clathrates. Such large methane eruptions will then warm the atmosphere at first in hotspots over the Arctic and eventually around the globe, while also causing huge temperature swings and extreme weather events, contributing to increasing depletion of fresh water and food supply, as further illustrated by the image below, from an earlier post.
[ click on image at original post to enlarge ]

October 2015 Sea Surface Temperature Update

The North Atlantic continues to be very warm. Sea surface temperature anomalies were as high as 7.9°C or 14.2°F at a location off the east coast of North America on October 22, 2015. Anomalies were 8.1°C or 14.5°F at that same spot on October 16, 2015.


Sea surface temperature anomalies were as high as 7.5°C or 13.6°F at a location near Svalbard on October 25, 2015. On October 9, 2015, sea surface temperatures were as high as 13.1°C or 55.6°F at that same location near Svalbard (marked by green circle on image below), an anomaly of 9.5°C or 17.2°F. These temperatures indicate that the water can be much warmer below the surface than at the surface, and that this warm water is transported by the Gulf Stream below the surface of the North Atlantic into the Arctic Ocean. The animation below switches between the above two dates and also shows that the cold freshwater lid on the North Atlantic has meanwhile extended further south.


In the Bering Strait, warm water also keeps flowing into the Arctic Ocean. At the location marked by the green circle on the image below, sea surface temperatures were as high as 7.3°C or 45.1°F on October 22, 2015, an anomaly of 5.7°C or 10.2°F.


Methane

The images below show high methane concentrations over the Arctic.


Above image shows methane levels at low altitude on October 22, 2015. Because of its height, there are no data at this altitude for Greenland. The image below shows methane concentrations at a higher altitude, with high methane levels showing up over Greenland on October 16, 2015.


Climate Plan

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

Malcolm Light comments

GLOBAL EXTINCTION IS NOW SIX YEARS CLOSER

The following comments refer to Figure 224 below. All historical floating ice appears to have been lost in the Arctic by September 2015 so we can assume that the 5+ year old ice pack has largely gone by this time. The 5+ year old ice pack was only predicted to melt back by 2021.7 consequently this year's volume of ice melting has occurred 6 years earlier than the previous prediction. The previous estimate of the final loss of 1 year Arctic floating ice from polynomial data was 2037.7 which now corrects to 2031.7, 16 years in the future.

Previous estimates of when the average atmospheric global temperature anomaly increase would reach 6°C was 2034.7, by which time massive global extinction would be proceeding. The new corrected time for this event is 2034.7 - 6 = 2028.7 which is 13 years in the future. During the major Permian Extinction event, which was caused by a massive methane build-up in the atmosphere, the mean surface atmospheric temperature increased by 5°C over 13 years. As the present mean global surface atmospheric temperature is already greater than 1°C hotter than the mean, we will be looking at at least a 6°C temperature increase by 2028 with its associated global extinction event. This is a frightening correlation between the new predicted 6°C average global surface atmospheric temperature rise and what is known to have occurred during the major Permian extinction event, both of which were caused by a massive buildup of methane in the atmosphere. We are clearly in for a very rough-hot ride in the next decade as the terminal global extinction event approaches.

Malcolm P.R. Light (Dr)
Earth Scientist
Figure 224. Arctic sea ice melt back times estimated from area, volume and thickness anomalies compared to various extinction zones defined by the global atmosphere temperature field. Credit: Malcolm Light. Click on image to enlarge.

Related

- Ocean Temperature Rise
http://arctic-news.blogspot.com/2014/10/ocean-temperature-rise.html

- Ocean Temperature Rise Continues

- Gulf Stream brings ever warmer water into Arctic Ocean
http://arctic-news.blogspot.com/2015/06/gulf-stream-brings-ever-warmer-water-into-arctic-ocean.html

- The Mechanism leading to Collapse of Civilization and Runaway Global Warming
http://arctic-news.blogspot.com/p/the-mechanism.html

- The Threat of Global Warming causing Near-Term Human Extinction
http://arctic-news.blogspot.com/p/threat.html

- Warming Arctic Ocean Seafloor Threatens To Cause Huge Methane Eruptions
http://arctic-news.blogspot.com/2015/09/warming-arctic-ocean-seafloor-threatens-to-cause-huge-methane-eruptions.html

- Climate Plan
http://arctic-news.blogspot.com/p/plan.html



NOAA analysis shows that the global sea surface in September 2015 was the warmest on record, at 0.81°C (1.46°F) above...
Posted by Sam Carana on Friday, October 23, 2015

Saturday, October 10, 2015

Arctic Sea Ice 2015 - update 11

Arctic sea ice extent has been growing rapidly recently. The image below shows extent up to October 9, 2015 (marked by red dot).


Below is a comparison of sea ice thickness as on October 6, for the years (from left to right) 2012, 2013, 2014 and 2015. The comparison shows that decline has been strongest where sea ice used to be the thickest, i.e. over 3 meters thick.


One of the reasons why the thickest Arctic sea ice has declined so dramatically over the years is the rising ocean heat that is melting the sea ice from underneath. The image below illustrates the situation on October 5, 2015, when sea surface temperature anomalies were as high as 6.4°C, 7.4°C and 7.3°C (11.5°F 13.2°F and 13.1°F) off the North American coast, and as high as 9.4°C (16.8°F) near Svalbard.


Water temperatures are very high in the Arctic, as further illustrated by the image below showing Arctic sea surface temperature anomalies as at October 9, 2015.



Rising ocean heat is further illustrated by the graph below, showing August sea surface temperature anomalies on the Northern Hemisphere over the years.
The situation is very dangerous, due to feedbacks and their interaction. The thicker sea ice used to act as a buffer, consuming ocean heat in the melting process. Without thicker sea ice, ocean heat threatens to melt the sea ice from below right up to the surface, causing the entire sea ice to collapse. As the sea ice declines, more open water will give rise to stronger winds and waves.

Furthermore, sunlight that was previously reflected back into space will instead be absorbed by the water, causing rapid rise of the temperature of the water. In places such as the East Siberian Arctic Shelf, the water is on a average only 50 m deep, so warmer water is able to reach the seafloor more easily there. As ocean heat keeps rising, there's a growing risk that heat will reach the Arctic Ocean seafloor and destabilize methane hydrates in sediments at the Arctic Ocean seafloor.

The image below shows a non-linear trend that is contained in the temperature data that NASA has gathered over the years, as described in an earlier post. A polynomial trendline points at global temperature anomalies of over 4°C by 2060. Even worse, a polynomial trend for the Arctic shows temperature anomalies of over 4°C by 2020, 6°C by 2030 and 15°C by 2050, threatening to cause major feedbacks to kick in, including albedo changes and methane releases that will trigger runaway global warming that looks set to eventually catch up with accelerated warming in the Arctic and result in global temperature anomalies of 16°C by 2052.

[ click on image to enlarge ]
The situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan.

Comparison of sea ice thickness on October 6, for the years (from left to right) 2012, 2013, 2014 and 2015, shows that...

Posted by Sam Carana on Saturday, October 10, 2015

Thursday, October 1, 2015

Cyclones continue to hit Northern Hemisphere

As the 2015 El Niño gets stronger, the Northern Hemisphere continues to get hit by strong winds and cyclones. The image below shows strong winds over the Arctic Ocean, as hurricane Joaquin approaches the coast of North America.



On above image, hurricane Joaquin is clocked at a speed of 79 mph (127 km/h) on October 1, 2015. NOAA warned that on that day the maximum sustained wind speed had increased to near 120 mph (195 km/h) with higher gusts.

For reference, NOAA uses four categories:
D: Tropical Depression – wind speed less than 39 mph (63 km/h)
S: Tropical Storm – wind speed between 39 mph and 73 mph (63 km/h - 118 km/h)
H: Hurricane – wind speed between 74 mph and 110 mph (118 km/h - 177 km/h)
M: Major Hurricane – wind speed greater than 110 mph (over 177 km/h)

NOAA issued the image below on September 30, 2015, warning that Hurricane Joaquin is likely to cause wind damage across a large part of the eastern coast of North America.


The NOAA animation below gives an idea of the strength of hurricane Joaquin.

[ click on image to enlarge, note that this is a 1.4 MB file that may take some time to fully load ]

Meanwhile, sea surface temperatures off the North American coast, as well as in the Arctic Ocean, are very high, as illustrated with the image on the right.

In the Arctic Ocean, the sea ice in many places is now less thick than it was in 2012, as illustrated by the image further below, showing sea ice thickness on October 7, 2012 (panel left) and a forecast for October 7, 2015 (panel right).

The water in the Arctic Ocean was already very warm this year. The main factor causing both these strong winds and the dramatic decrease in thickness of the multi-year sea ice is ocean heat, as also illustrated by the image below, showing high sea surface temperature anomalies in the Arctic as at September 30, 2015.


As the image below shows, nearly all the thick (over 3 m) multi-year sea ice has now disappeared, setting up a dangerous situation for the future that is much more dangerous than the situation was back in 2012. The thicker sea ice used to act as a buffer, consuming ocean heat in the melting process. Without thicker sea ice, ocean heat threatens to melt the sea ice from below right up to the surface, causing the entire sea ice to collapse as more open water will go hand in hand with stronger winds and waves. In case of such a collapse, sunlight that was previously reflected back into space will instead be absorbed by the water, causing rapid rise of the temperature of the water. In places such as the East Siberian Arctic Shelf, the water is on a average only 50 m deep, so warmer water is able to reach the seafloor more easily there.


The water of the Arctic Ocean is very warm, not only at the surface, but even more so underneath the surface. The danger is that strong winds will mix warm water all the way down to the seafloor, where it could destabilize sediments that can contain huge amounts of methane in the form of hydrates and free gas.

[ click on image to enlarge ]
The image on the right illustrates the impact of winds over the East Siberian Arctic Shelf on September 26, 2015.

NSIDC specialist Julienne Stroeve recently warned"In 2007 more than 3m of bottom melt was recorded by [an] ice mass balance buoy in the region, which was primarily attributed to earlier development of open water that allowed for warming of the ocean mixed layer. But perhaps some of this is also a result of ocean mixing."

As discussed in an earlier post, sea surface anomalies of over 5°C were recorded in August 2007 in the Arctic Ocean. 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 and bottom water temperatures on the mid-shelf increased by more than 3 degrees Celsius compared to the long-term mean.

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



As the 2015 El Niño gets stronger, the Northern Hemisphere continues to get hit by strong winds and cyclones. The image...
Posted by Sam Carana on Thursday, October 1, 2015