Showing posts with label jet stream. Show all posts
Showing posts with label jet stream. Show all posts

Sunday, November 30, 2014

Another Heatwave Hits Arctic

As parts of Canada, Greenland and Russia are hit by -40 degrees temperatures (anomalies at the bottom end of the scale), parts of the Arctic are experiencing temperatures above freezing (anomalies at the top end of the scale), as illustrated by the image below.

[ click on image to enlarge ]
Temperatures in the Arctic are much higher than they used to be and this situation further accelerates warming in the Arctic, due to a number of feedbacks.

One such feedbacks has been coined the ‘open doors feedback’. Indeed, the situation is much like leaving the fridge door open. This allows cold air to more easily move out of the fridge, i.e. the Arctic, resulting in the cold temperatures over North America that have received extensive news coverage in the media. At the same time, warm air can move more easily into the fridge, i.e. the Arctic, and this is one of the reasons why the Arctic is hit by temperatures that are so much higher than what used to be normal.

The situation has been described in a number of earlier posts such as this one, as well in a recent interview with Jennifer Francis. As the Arctic warms more rapidly than the rest of the world, there's less temperature difference between the Arctic and the equator, resulting in the jet stream going around the globe at a lower speed with more elongated loops.

The left chart on above image shows such an elongated loop going north along the east coast of Greenland, then bending before Scandinavia and moving over the north of Greenland, then going around the North Pole and moving back to Scandinavia. This loop is not very visible on the chart, because the jet stream moves faster along straight tracks, and this chart highlights wind speed more than it highlights the path of the jet stream. Yet, the shape of this loop is very important, as it traps warmer air north of Greenland.

BTW, a weaker jet stream also elevates the chance of heat waves elsewhere, which can indirectly warm up the Arctic. Examples of this are heat waves over the Gulf Stream as it crosses the Atlantic Ocean, resulting in warmer water being carried into the Arctic Ocean, and heat waves over Siberia and North America, resulting in warming up of rivers that end in the Arctic Ocean.

Anyway, to get back to the current heatwave, there are a number of reasons why temperatures in the Arctic are so high at the moment. One of the biggest reasons is ocean heat, which has reached very high levels, especially in the North Atlantic, while the Gulf Stream keeps transporting warmer water from the North Atlantic into the Arctic Ocean (i.e. water that is warmer than the water in the Arctic Ocean). This warms up the seafloor of the Arctic Ocean, resulting in methane erupting from the seafloor, with a strong immediate local warming impact in the Arctic, thus further accelerating warming in the Arctic in another one of these self-reinforcing feedback loops, as pictured in the image below.



Further feedbacks that accelerate warming in the Arctic are discussed at the feedbacks page.

Without effective and comprehensive action, these feedbacks threaten to lead to runaway warming, i.e. abrupt climate change causing mass death and destruction, and resulting in extinction at massive scale, as depicted in the image below and as described in this earlier post.



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



Saturday, November 22, 2014

How melting Arctic ice is driving harsh winters

by Nick Breeze

The very least 'global warming' could do for us is to give us warmer winters, right? Wrong, writes Nick Breeze, who met climate scientist and meteorologist Jennifer Francis in his attempt to understand the complex interactions of jet stream, polar vortex, the melting Arctic, and the extreme snowfall that's hitting the northeast US right now.

"Historic" snowfalls have the US northeast this week, with Buffalo, New York under an astonishing 2.4m (8ft) of snow - enough to cause some roofs to cave in under the pressure.

It's just the latest chapter in 2014 unprecedented range of weather extremes - from persistent storms that battered, and flooded much of the UK at the beginning of the year, before going on to record the hottest October since records began.

And in the US, extremes have ranged from California's record drought, to the early snows now under way in the northeast - and let's not forget the 'polar vortex' that hit much of the US in January, bringing Arctic conditions as far south as Texas and Florida, causing flights to be cancelled in Chicago as aviation fuel froze in the -38.3C (-37F) temperatures.



Scientists now have evidence that these persistent extreme weather patterns are increasing in their frequency, due to the rapid heating up of the Arctic that is changing the behaviour of the jet stream, and in turn, the polar vortex.

And Jennifer Francis of Rutgers University, one of the leading US scientists studying the relationship between Arctic warming and changes in the jet stream, believes that it's thanks to 'global warming' that northern hemisphere weather is becoming more extreme - and it's not about to get any better.

Screenshot from Youtube video further below

The 'vast river of wind' that makes our weather

"The Arctic is generally very cold", she told me, "and the areas farther south are warm, and that difference in temperature between those two areas is really what fuels that vast river of wind moving high over our head that we call the jet stream."

"The jet stream in turn creates most of the weather that we feel all around the northern hemisphere and the middle latitudes, so anything that affects this jet stream is going to affect weather patterns. So as the Arctic warms up much faster than the areas farther south, we're seeing this temperature difference between these two regions get smaller."

The result of that, she explains, is that the atmospheric forces driving the jet stream's circular motion are getting smaller - and that means the winds themselves in the jet stream are getting weaker, and moving more slowly.

"When that happens, the jet stream tends to take a wavier path as it travels around the northern hemisphere and those waves are actually what create the stormy patterns and the nice weather patterns. As those waves get larger because of this weakening of those winds of the jet stream, they tend to move more slowly from west to east."

"That means it feels like the weather patterns are sticking around longer, because those patterns are moving much more slowly and this then makes it more likely to have the kind of extreme events that are related to persistent weather patterns."



Are critical findings influencing policy?

These changes in climate have huge implications. As Dr Francis points out, there are "people who worry about whether there is enough fresh water to supply cities, whether there is enough snowpack on mountains to supply reservoirs, and for agriculture ..."

"Drought and agriculture is a big problem. Storminess in certain areas is another big problem. Yes, it has a huge impact for a whole range of issues that affect the way we live."

It's no wonder then that Dr Francis and her colleagues have attracted the attention of President Obama's chief science advisor, Dr John Holdren.

Dr Holdren has been reporting directly to the President on the real time effects of climate change and is keen to understand what this new research tells us about the future impact of changes to the jet stream.

Asked about this sudden interest in her work from the US Presidency, Francis muses thoughtfully. "Yes, we've had a lot of interest from policy makers", she acknowledges.

"I think we're starting to make a lot of progress now in getting policymakers to understand that this is a big problem they have to face ... I think decision makers and the policymakers at the local level get it much better because they're already seeing effects on their local areas.

"Sea level rise is an obvious one. They're already seeing changes in drought and agricultural problems and dealing with fresh water issues. It is really at the local level that we're having more success."

New research supports the case that Arctic sea ice loss is driving climate changes

So to understand the changes in the jet stream it's important to research how the vast atmospheric river of weather above our heads is connected to other climate mechanisms.

"It appears that over the north Atlantic, and towards Asia, there's a mechanism that appears to be quite robust, and several groups have found this mechanism using completely different analysis techniques", says Francis referring to new research by colleagues at the University of Alaska that has emerged in the last couple of months.

"So what we're finding is that there's an area, north of Scandinavia in the Arctic, where the ice has been disappearing particularly rapidly. When that ice disappears ... there is unfrozen ocean underneath, and that ocean absorbs a lot more energy from the sun through the summertime. So it becomes very warm there."

"Then as the fall comes around, all that heat that's been absorbed all summer long, where the ice has retreated, is put back in the atmosphere and that creates a big bubble of hot air ... over that region where the ice was lost."

And in turn, that goes on to disrupt the circumpolar winds whose behaviour determines much the weather across the northern hemisphere.

The gigantic bubble of warm air "tends to create a northward bulge in the jet stream", and in turn, "that creates a surface high pressure area that circulates in the clockwise direction. That sucks cold air down from the Arctic over northern Eurasia, and that creates a southward dip in the jet stream."



The bulging jet stream disrupts the polar vortex

"So what we're getting is this big northward bulge up over Scandinavia and a southward dip over Asia ... creating, first the tendency for a larger wave in the jet stream, which tends to move more slowly, but also we're seeing this mechanism that creates these colder winters that have been observed over Central Asia."

"Once the jet stream gets into this wavier pattern, it sends wave energy up into the highest levels of the atmosphere, which is called the stratosphere, where we have the polar vortex, which is kind of similar to the jet stream but it's much higher up in the atmosphere and it travels much faster."

"So as that wave energy gets sent up from this larger wave below, up into the stratosphere, it breaks down that polar vortex so that it becomes wavier as well. That wavier polar vortex sends energy back down to the lower atmosphere and it creates an even wavier jet stream in February."

"So we're seeing this connection of mechanisms that starts with Arctic sea ice loss and it makes a wavier jet stream for different reasons all the way through winter."

Will the jet stream continue to cause changes in climate?

By identifying these mechanisms and linking them back directly to loss of the Arctic sea ice, Dr Francis and her colleagues are demonstrating how man-made global warming is creating feedbacks that are changing the climate conditions in the northern hemisphere - and not for the better.

It may be counterintuitive, and it when it first happened it took scientists by surprise - but now it looks like this is one of the most important ways in which 'global warming' is hitting North America. Melting ice in the Arctic Ocean is indirectly pushing frigid Arctic air south across the continent, creating the perfect conditions for massive snowfall.

Which is all very well ... but what's coming next? "We are using these climate models, or computer simulations ... to try and project what we're expecting to see happen in the future, as greenhouse gases continue to increase.

"The early indications are that these large wavy patterns in the jet stream are going to become more frequent in the future, as far as we can tell. It is preliminary research that I haven't published yet but it does look as if they are going to increase."



Nick Breeze is a film maker and writer on climate change and other environmental topics. He has been interviewing a range of experts relating to the field of climate change and science for over four years. These include interviews with Dr James Hansen, Professor Martin Rees, Professor James Lovelock, Dr Rowan Williams, Dr Natalia Shakhova, Dr Michael Mann, Dr Hugh Hunt, among others.

Additional articles can also be read on his blog Envisionation.

Jennifer Francis is a research professor at the Institute of Marine and Coastal Sciences at Rutgers University, where she studies Arctic climate change and the link between Arctic and global climates. She has authored more than 40 peer-reviewed publications on these topics. She was also the co-founder of the Rutgers Climate and Environmental Change Initiative.

Article earlier posted at TheEcologist.org




Related





Saturday, September 6, 2014

Antarctica linked to Arctic

Waters in the Arctic Ocean continue to warm up. Very warm waters from the North Atlantic and Pacific Ocean are invading the Arctic Ocean.



Waters in the North Atlantic and in the North Pacific are very warm, due to a number of reasons.

What is happening in the oceans is very important in this respect. As discussed in earlier posts, most of the extra heat caused by people's emissions goes into the oceans.

The great ocean conveyor belt (Thermohaline Circulation), brings warm water from the southern hemisphere to the northern hemisphere.

The Gulf Stream is the North Atlantic leg of the great ocean conveyor belt, and it brings dense, salty water from the North Atlantic into the Arctic Ocean.

Saltier water is denser than fresher water because the dissolved salts fill interstices between water molecules, resulting in more mass per unit volume.

Very dense ocean water can be found in the North Atlantic because the North Atlantic has high salinity, due to high evaporation rates, while salty water is also coming from the Mediterranean Sea.

As also discussed in an earlier post, this dense, saltier water sinks in the North Atlantic, accumulating in deeper water.

By contrast, much of the Arctic Ocean has low salinity, due to ice melt and river runoff.  As it enters the Arctic Ocean, the warm and dense water from the Atlantic thus dives under the under the sea ice and under the less salty surface water in the Arctic Ocean.

In conclusion, much of the heat resulting from people's emissions accumulates in the North Atlantic and also ends up in the Arctic. This partly explains why surface temperatures are rising much faster at the poles, as illustrated by the NOAA image below.


There are further reasons why surface air temperatures elsewhere (other than at the poles) are rising less rapidly than they did, say, a decade ago. As also discussed by Andrew Glikson in the post No Planet B, the increased amounts of sulphur emitted by the growing number of coal-fired power plants and by the burning of bunker fuel on sea is (temporarily) masking the full wrath of global warming.

Another reason is the growth of the sea ice around Antarctica, as illustrated by the CryosphereToday image on the left.

Melting takes place both in the Arctic and on Antarctica, but more so in the Arctic. Recent research of CryoSat-2 data reveals that Greenland alone is now losing about 375 cubic kilometers of ice annually, while in Antarctica the annual volume loss now is about 125 cubic kilometers.

Currents also distribute ocean heat in ways that make the Arctic warm up more than twice as rapidly as the Antarctic. In a recent paper, John Marshall et al. further suggest that ozone depletion also contributes to this.

All this makes that, while the jet streams on the northern hemisphere are circumnavigating the globe at a slower pace, jet streams on the southern hemisphere are getting stronger, making it more difficult for warm air to enter the atmosphere over Antarctica, while the stronger winds also speed up sea currents on the southern hemisphere. This makes the sea ice around Antarctica grow, and as the sea ice spreads further away from Antarctica, temperatures of surface waters around Antarctica are falling.

Growth of the sea ice around Antarctica makes that more sunlight is reflected back into space. There now is some 1.5 million square kilometers more sea ice around Antarctica than there used to be. The albedo change associated with sea ice growth on the southern hemisphere can be estimated at 1.7 W/sq m, i.e. more than the total RF of all CO2 emission caused by people from 1750 to 2011 (IPCC AR5).


The rapid growth of sea ice on the southern hemisphere alone goes a long way to explain why, over the past three months, surface air temperatures have not been much higher than they used to be, both globally and in the Arctic, as illustrated by above NOAA image. What has also contributed to warmer temperatures around latitude 60 on the northern hemisphere is the fact that methane has accumulated in the atmosphere at that latitude, as discussed in earlier posts.

Arctic SST far exceed anything ever seen in human history
So, does the sea ice on the southern hemisphere constitute a negative feedback that could hold back global warming? It doesn't.

It may temporarily keep surface temperatures close to what they used to be, as the sea ice reflects lots of sunlight back into space, but at the same time ocean temperatures are rising strongly, as the sea ice also prevents heat from radiating out of the waters around Antarctica.

The latter also helps explaining the colder surface temperatures over those waters.

Much of this additional ocean heat has meanwhile been transported by the great ocean conveyor belt to the northern hemisphere.

No time before in human history has such a huge amount of ocean heat accumulated in the North Atlantic and the North Pacific. This heat is now threatening to invade the Arctic Ocean and trigger huge temperature rises due to methane eruptions from the seafloor.


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

Wednesday, July 2, 2014

What's wrong with the weather?


Above map shows temperatures in NewFoundland and Labrador close to 30°C (86°F), compared to temperatures in Albuquerque, New Mexico of only 20°C (68°F), while temperatures seem to be even lower in Mexico City. What's happening with the weather?

Jet Streams are changing


World climate zones used to be kept well apart by jet streams. On the northern hemisphere, the polar jet stream was working hard to separate the Tundra and Boreal climate zones' colder air in the north from the Temperate climate and the Subtropical climate zones' warmer air in the south.

As the Arctic is warming even faster than the Equator, the falling temperature difference between the two reduces the speed at which warm air is moving from the Equator to the North Pole. This in turn slows the speed at which the jet streams are circumnavigating the globe on the Northern hemisphere and it is deforming the jet streams in other ways as well.

NOAA image ]
As above image shows, the polar jet stream is typically located at about 60°N and the subtropical jet stream at about 30°N. The polar jet stream's altitude typically is near the 250 hPa pressure level, or 7 to 12 kilometres (4.3 to 7.5 mi) above sea level, while the weaker subtropical jet stream's altitude is higher, between 10 and 16 kilometres (6.2 and 9.9 mi) above sea level.

NOAA image
The polar jet stream used to travel at speeds of up to 140 miles per hour, while following a relatively straight track that was meandering only slightly, i.e. with waves that go up and down only a little bit. This fast and relatively straight jet stream kept climate zones well apart. Accordingly, the Northern Temperate Zone used to experience only mild differences between summer and winter weather, rather than the extremely hot or cold temperatures that we're increasingly experiencing now.

Polar jet stream (blue) & subtropical
jet stream (red) - NOAA image
Loss of snow and ice cover in the north is accelerating warming in the Arctic. This is decreasing the difference in temperature between the Arctic and the Northern Temperate Zone, in turn causing the polar jet to slow down and become more wavy, i.e. with larger loops, as illustrated by the animation below.

Imagine a river that at first rapidly runs down a narrow and straight path when its waters fall down from the top of a high mountain. Once that river flows through flat land, though, it becomes slow and curvy.

Similarly, the polar jet stream is now circumnavigating the globe at slower speed and along a wavier tracks. Its waves are now more elongated, more stretched out vertically, making that cold air can move more easily down from the Arctic, e.g. through the middle of North America, as illustrated by the animation below.

At the same time, warm air can move up more easily from the South into the Arctic. This is creating huge temperature anomalies in many places, as also illustrated by the animation below.


[ This animation is a 1.4MB file that may take some time to fully load ]
                Diagram of Doom, Sam Carana
These changes to polar jet stream constitute a self-reinforcing feedback that is further accelerating warming in the Arctic. As the jet stream slows down and its waves become more elongated, cold air can leave the Arctic more easily and descend deep into the Northern Temperate Zone. Conversily, more warm air can at the same time move north into the Arctic. The result is a warmer Arctic.

This 'open doors' feedback further decreases the difference in temperature between the Arctic and the Northern Temperate Zone, in turn further slowing down the jet stream and making it more wavy, and thus further accelerating warming in the Arctic.

This feedback is pictured in the image below as feedback #10.


Diagram of Doom - see Feedbacks in the Arctic for links


Arctic sea ice in steep descent

Global warming and the numerous feedbacks have a devastating impact on the sea ice, which is currently showing an almost vertical fall in extent, as illustrated by the image below.



Oceans are turning red

Arctic sea ice is also under threat from very warm waters. As the image below illustrates, oceans are turning red around the globe.



The image below shows that where the sea ice disappears, sea surface temperature anomalies as high as 8°C and higher show up.


Comprehensive and Effective Climate Action

The situation is dire, as huge amounts of methane are contained in sediments underneath the seafloor of the Arctic Ocean. Loss of sea ice means that huge amounts of heat that was previously reflected back into space will be absorbed by the Arctic Ocean. Furthermore, heat that previously went into melting the ice will also be absorbed by the water. Comprehensive and effective action is needed, as discussed at the Climate Plan blog.




Friday, May 16, 2014

More extreme weather can be expected



The heaviest rains and floods in 120 years have hit Serbia and Bosnia this week, Reuters and Deutsche Welle report.

The animation below shows the Jet Stream's impact on the weather. Cold temperatures have descended from the Arctic to Serbia and Bosnia in Europe and all the way down to the Gulf of Mexico in North America, while Alaska, California, and America's East Coast are hit by warm temperatures. In California, 'unprecedented' wildfires and fierce winds lead to 'firenadoes', reports CNN.



The image below shows that on May 15, 2014, the wind approaching Serbia and Bosnia at 700 hPa reached speeds of up to 120 km per hour (75 mph), as indicated by the green circle on the main image and inset.


The image below, from skeptical science, shows the cyclonic spin that can be expected in a through such as the one that hit Serbia and Bosnia recently.


As the Jet Stream changes, more extreme weather events can be expected. What makes the Jet Stream change? As the Arctic is warming up faster than the rest of the world, the temperature difference between the Arctic and the equator decreases, in turn decreasing the speed at which the Jet Stream circumnavigates the globe. This can cause 'blocking patterns', with extreme weather events hitting an area longer than before.

As the jet stream becomes wavier, cold air can more easily descend from the Arctic down to lower latitudes in a downward through of the Jet Stream, while warm air can more easily reach higher latitudes in an upward ridge of the Jet Stream.

This spells bad news for many areas across the world that can be expected to be hit by more extreme weather events such as heatwaves, wildfires fuelled by stronger winds and more intense drought, storms and floods.

Heatwaves are a huge threat in the Arctic, especially when followed by storms that can cause warm surface water to mix down to the bottom of the sea and warm up sediments under the seafloor that can contain huge amounts of methane in the form of hydrates and free gas. The situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan blog.


Related

- Extreme weather strikes around the globe - update
http://arctic-news.blogspot.com/2014/02/extreme-weather-strikes-around-the-globe-update.html

- Escalating extreme weather events to hammer humanity (by Paul Beckwith)
http://arctic-news.blogspot.com/2014/04/escalating-extreme-weather-events-to-hammer-humanity.html

- Our New Climate and Weather (by Paul Beckwith)
http://arctic-news.blogspot.com/2014/01/our-new-climate-and-weather.html

- Our New Climate and Weather - part 2 (by Paul Beckwith)
http://arctic-news.blogspot.com/2014/01/our-new-climate-and-weather-part-2.html

- Changes to Polar Vortex affect mile-deep ocean circulation patterns
http://arctic-news.blogspot.com/2012/09/changes-to-polar-vortex-affect-mile-deep-ocean-circulation-patterns.html

- Polar jet stream appears hugely deformed
http://arctic-news.blogspot.com/2012/12/polar-jet-stream-appears-hugely-deformed.html



Saturday, April 5, 2014

Escalating extreme weather events to hammer humanity


By Paul Beckwith

Extreme weather events are rocketing upwards in their frequency of occurrence, intensity, and duration and are impacting new regions that are unprepared. These events, such as torrential rains, are causing floods and damaging crops and infrastructure like roads, rail, pipelines, and buildings. Cities, states, and entire countries are being battered and inundated resulting in disruption to many peoples lives as well as enormous economic losses. As bad as this is, it is going to get much worse by at least 10 to 20 times. Why?

Greenhouse gas emissions from humans have changed the chemistry of the atmosphere. The optical absorption of infrared heat has increased in the atmosphere which raises temperature, and thus water vapor content, and therefore fuels more intense storms. The jet streams that guide these storms are slower and wavier and more fractured and cause our weather gyrations and weird behavior. Areas far north can get very warm, while areas far south can get very cold. Some areas get persistent drought. Then, the pattern can flip. The jet streams are much wavier in the north-south direction since the Arctic temperatures have warmed 5 to 8 times faster than the global average. This reduces the temperature difference between the Arctic and equator and basic physics forces the jets to slow and get wavier.

Why is the Arctic warming greatly amplified? The region is darkening and thus absorbing more sunlight, since the land-based snow cover in spring and the Arctic sea ice cover volume are both declining exponentially. The white snow and ice is being replaced by dark surfaces like the ocean and the tundra. The most detailed computer model on sea ice decline is a U.S. Naval Graduate School model, and it shows the sea ice cover could be gone by late summer in 2016. If this happens, the Arctic warming will rocket upwards, the jets will distort much more, and the extreme weather events will rocket upwards in frequency, amplitude, and duration and civilization will be hammered.


Paul Beckwith
Paul Beckwith is part-time professor with the laboratory for paleoclimatology and climatology, department of geography, University of Ottawa. Paul teaches climatology/meteorology and does PhD research on 'Abrupt climate change in the past and present'. Paul holds an M.Sc. in laser physics and a B.Eng. in engineering physics and reached the rank of chess master in a previous life. Below are Paul's earlier posts at the Arctic-news blog.


Paul Beckwith with sign (arrows highlighted by 
Sam Carana, from earlier post)

Below, a recent video in which Paul Beckwith discusses how a weaker Jet Stream lets warmer air move from lower latitudes into the Arctic (feedback #10).


From December, 2013 until early April, 2014 there have been persistent and very large temperature anomalies in the northern hemisphere (+20 C = +36 F in the Arctic, -20 C = -36 F in vast parts of the US and Canada). I claim that this represents a previously unrecognized large positive feedback acting to homogenize the temperature in the northern hemisphere.



Earlier posts by Paul Beckwith

- Abrupt Climate Change

- Our New Climate and Weather - part 2

- Our New Climate and Weather

- Are Alberta’s Tar Sands prepared for a torrential rain event?

- Stop All New Fossil Fuel Megaprojects

- Toward Genuinely Improved Discussions of Methane & Climate

- The Social Tipping Point

- Arctic Cyclone July 2013

- Arctic Ocean Events - Videos by Paul Beckwith

- Climate change fighting town savaged by runaway oil train

- Extreme weather becomes the norm - what can you do?

- Thin Spots developing in Arctic Sea Ice

- The Tornado Connection to Climate Change

- Anthropogenic Arctic Volcano can calm climate

- Hold on folks… the times they are a-changin’

- Hurricane Sandy moving inland

- Open Letter to Canadian MPs

- State of Climate Change October 2012

- Is death by lead worse than death by climate? No.

- You are now entering the nonlinearity zone…

- Vanishing Arctic sea ice is rapidly changing global climate

- Storm enters Arctic region

- Update on September Arctic cyclone

- Arctic cyclone warning for September 7

- Paul Beckwith on ice speed and drift - update 1

- Paul Beckwith on ice speed and drift

- Another Arctic Cyclone brewing

- Sea ice in the Arctic - Shaken and stirred (by a powerful cyclone)

- How to part ways with a climate denier that has incredible stamina...



Tuesday, April 1, 2014

Earthquakes in the Arctic Ocean

Earthquakes in the Arctic Ocean
indications of immiment 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 laters, 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 occured 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 reveberate 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 noticable 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 volcanos 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 calls for comprehensive and effective action as discussed at the Climate Plan blog.





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
http://climateplan.blogspot.com




Saturday, February 15, 2014

Extreme weather strikes around the globe - update

As the weather gets more extreme, disaster strikes around the globe. The Guardian reports three people killed as storms continue to batter southern UK. The Vancouver Sun reports that a U.S. Northeast snowstorm kills 25. And the Sacramento Bee reports Six dead and 1,000 injured in fresh Japan snow storm.

What is the story behind these extreme weather events? The image below tells the story. The Arctic has been much warmer than it used to be, due to numerous feedbacks that accelerate warming in the Arctic. This reduces the temperature differential between the Arctic and lower latitudes, which changes the Jet Stream and Polar Vortex, in turn making the weather at many places ever more extreme.

 earlier forecasts by cci-reanalyzer.org
Above image illustrates the situation, showing an Arctic Ocean that is warmer than the higher latitudes of the Asian and North American continents.

Arctic sea ice has meanwhile reached record lows, as illustrated by the image below.


The situation can be expected to get even worse. The image below shows sea ice extent, as measured by the NSIDC, which is one day ahead compared to above image.


Below, two regular contributors to the Arctic-news blog comment on the situation.




    Paul Beckwith:

Paul Beckwith with sign (arrows highlighted by Sam Carana, from earlier post)
In the video below, Paul Beckwith discusses the above sign and the situation in general.





Dr. Malcolm Light, Earth Scientist, comments:


The volume of water transported by Gulf Stream off the east coast of the United States has increased by three times since the 1940s due to a massive increase in wind drag. This increase in the south westerly wind drag is a result of the continuously increasing pressure difference set up between the continental air mass over North America, heated by fossil - fuel generated carbon dioxide, and the marine air of the Atlantic.

The increased energy entering the Gulf Stream as heat and its associated winds and storm systems are what are now pummeling Great Britain and Europe. This heat is also transported further north by branches of the Gulf Stream into the Arctic Ocean, where it is destabilizing the subsea methane hydrates, releasing increasing volumes of methane into the Arctic atmosphere and causing temperature anomalies this last winter of more than 20 degrees Celsius.

As a consequence of the extremely high Arctic temperatures and pressures, the normal freezing Arctic air has been displaced into Canada and the United States, causing catastrophic blizzards that have never been seen before. When the floating Arctic ice cap melts towards the end of next year, the Arctic Ocean will then become more aggressively heated by the sun and the northern offshoots of the Gulf Stream.

Under these circumstances, the cold Arctic air will be confined over the Greenland ice cap and the Arctic atmosphere will rotate anticlockwise around Greenland, transferring the fast-increasing amounts of its atmospheric methane to Canada and the United States and causing a further increase in the energy of the Gulf Stream.

Therefore the United Kingdom and Europe must brace themselves for even more catastrophic weather systems, widespread flooding and massive wind damage from the start of the last quarter of next year.


Below is a comparison of methane readings for the week from February 9 to 16, 2014, compared to the same period in 2013.


The comparison shows that there is a lot of methane over the Arctic Ocean that wasn't there last year. Furthermore, high methane readings show up where currents move the sea ice out of the Arctic Ocean, in areas such as Baffin Bay. This indicates that methane that is released from the seafloor of the Arctic Ocean appears to be moving underneath the ice and entering the atmopshere where the sea ice is fractured or thin enough to allow the methane to pass through.

Also note that more orange areas show up on the southern hemisphere in 2014, indicating that more methane from the northern hemisphere is now spreading south beyond the equator. This in addition to indications that more methane is rising and building up at higher altitudes, as discussed in an earlier post.

As said before, the situation calls for comprehensive and effective action, as discussed at the Climate Plan blog.



Monday, February 10, 2014

Extreme weather strikes around the globe

  Editorial note: this post has meanwhile been updated as
Extreme weather strikes around the globe update.


As the weather gets more extreme, disaster strikes around the globe.

Here's a snapsnot from today's news. In London, the BBC reports, flooded homes along the River Thames are being evacuated and thousands more are at risk. In Japan, reports Reuters, eleven people died, more than a thousand were injured and tens of thousands lost power when the worst snowstorm in decades hit Tokyo and areas around the Japanese capital before heading north to blanket the tsunami-hit Pacific coast. Many countries in the Middle East were hit by snow. The BBC reports that heavy snow in northern Iran has left around 480,000 homes without power and some towns and villages cut off.

What is causing these extreme weather events? The image below tells the story. While at times it has been cold at many places around the world, when averaged over the past 30 days, temperatures around the globe have actually been several degrees higher than they used to be. The Arctic has been hit hardest, with anomalies as high as 21°C over this 30 day period. This affects the Jet Stream and Polar Vortex, which in turn is making the weather ever more extreme.



The situation is further illustrated by the cci-reanalyzer.org forecasts below.



And while the sea ice didn't look too bad at the start of the year, growth has meanwhile stopped, as illustrated by the image below.


Added below are two videos by Paul Beckwith, further discussing the situation.





Editor's note: Reanalysis of temperature anomaly Jan 12 - Feb 10, 2014.
Meanwhile, I've added another image (above), created with NOAA's reanalysis, which compares temperatures to a larger dataset, and the colors look a lot different, so NOAA may indeed have mixed the colors up somewhat in the initial image, as Albert suggested at the Facebook discussion (click on image below).

Anyway, the point made in the post remains, i.e. that as global warming continues, warming in the Arctic accelerates more rapidly than at lower latitudes, which weakens the polar vortex and jet stream in a self-reinforcing feedback that causes the Arctic to warm up even further compared with lower latitudes.

As said, the situation calls for comprehensive and effective action, as discussed at the Climate Plan blog.