Support the Arctic Sea Ice Forum and Blog

Author Topic: 20 Year Build up of Arctic Fresh Water May Flood N Atlantic & Stall Gulf Stream  (Read 5848 times)

FishOutofWater

  • ASIF Middle Class
  • Posts: 685
    • View Profile
  • Liked: 201
  • Likes Given: 88

"Figure 3 Time series of freshwater content in different layers of the Beaufort Gyre region. Blue bars depict total liquid freshwater content. Black bars show freshwater content in sea ice. Yellow bars – freshwater content in the mixed layer, red bars – in the Pacific and green bars – in the Atlantic water layer. Freshwater content is shown in thousand cubic kilometers. Upper left bars shows total annual freshwater flux into the Arctic Ocean from all rivers; green and black small bars show errors in liquid and sea ice freshwater content estimates. All freshwater contents are calculated relative to 34.8 reference water salinity."

The build up in volume from 2002 to 2015 is about the volume of Lake Michigan which stores 4,918 cubic km of water.


Huge volumes of fresh water have been building up over the past 20 years in the Arctic waters north of Alaska. A volume the size of Lake Michigan built up from 2003 through the end of 2015. Before the 1990’s there were regular cycles of fresh water build up and release within decades as periods of high pressure north of Alaska were followed by periods of stormy weather. Scientists suspect that over the past 20 years large amounts of melt water from Greenland’s glaciers have changed the dynamics of the North Atlantic ocean and the Arctic atmosphere. Since the 1990’s a dome of high pressure has persisted in the Beaufort sea and the anticyclonic winds have pumped fresh water towards the high’s center building up a mound of relatively fresh water over a huge area north of Alaska. The primary source of the fresh water is rivers that flow into the Arctic. Over the past several decades, sea ice melting has added about 20%  to the increase of fresh water in the Beaufort sea.
The freshwater content of the Beaufort gyre  increased by a volume the size of lake Michigan from the 1970s to 2008.

A major 2008 report by a team of scientists led by Wood’s Hole oceanographer Andrey Proshutinsky found an increase of 5000 km3 of fresh water from the 1970s to 2008. www.whoi.edu/

From 2008 to 2015 an additional 2000 km3 was added so the total increase in fresh water is 7,000km3. The total volume of the world’s second largest lake by volume, Lake Michigan, is just under 5,000km3.

The freshwater content of the Beaufort gyre  increased by a volume the size of lake Michigan from the 1970s to 2008.

 Preliminary data from the BGOS 2008 cruise indicate that the FWCL in the BG continued to rise in 2008 and reached 21,000 km3 – a historical maximum from all available years of observations. Compared to 1970s climatology (the pre-90s decade with the most extensive data coverage, (Figure 1) there has been a FWCL increase in the BG of approximately 5,000 km3. This is comparable with the volume of fresh water annually delivered to the Arctic Ocean by rivers and through Bering Strait (5700 km3 per year, Serreze et al., [2006]).
https://www.whoi.edu/beaufortgyre/pdfs/2008JC005104-pip.pdf

The freshwater layer in the Beaufort sea deepened by 3 meters - about 10 feet from 2003 to 2007. Because the Beaufort gyre covers a large area, this is a huge volume of fresh water. Anticyclonic winds associated with persistent high pressure in 2007 caused Siberian and North American river water and water from a record melt of sea ice in 2007 to flow into this Arctic sea north of Alaska.

The persistent anticyclonic Beaufort high pressure builds up a mound of water under it because the direction of a mass of water moves to the right of the wind  direction in the northern hemisphere because  the rotation of the earth gives the water spin. See this post at Neven’s sea ice blog by an Arctic oceanographer for details. neven1.typepad.com/...

On the other hand, cyclonic rotation associated with low pressure areas causes water to well up from below the center of the low. Thus  years of high pressure followed by  years of storminess cause moderate periodic surges of fresh water from the Arctic to the north Atlantic ocean. It was like the Arctic breathed in fresh water then breathed it out in a period of a decade or less. The largest observed freshwater surge called the “Great Salinity Anomaly” happened in the early 1970’s.

The Great Salinity anomaly was one of the likely causes of the brutal American winters of the 1970s. Fresh water tends to float over denser warm salty Gulf Stream water in sub-Arctic seas of the north Atlantic. This keeps the warm salty water from releasing its heat to the atmosphere and sinking thousands of feet into the deep Atlantic. This disruption of the thermohaline circulation is popularly called slowing down the Gulf Stream. The deep overturning circulation brings Gulf Stream water to the subarctic seas, warming Europe and north America. When deep water formation slows brutal winters tend to follow.  This effect, combined with the reflective effects of growing levels of sulfuric acid pollution over the north Atlantic in the 1960s and 1970s caused cold north American and European winters  in those decades. This cool period that broke up the trend of greenhouse gas caused global warming that has been ongoing since the turn of the twentieth century has been intentionally misinterpreted by climate change deniers to confuse politicians and the public about climate change.


Winters were miserably cold in Minnesota and the central and eastern U.S. in the 1970s.

Last spring, following the extremely abrupt collapse of the winter polar vortex in a sudden stratospheric warming a very intense Beaufort high developed driving more fresh water into the gyre. The strong high pressure in the sunny spring months melted out the ice early. Midwinter high pressure under dark skies is favorable for ice growth but under the bright long sunny days of May the ice melted and the water took up enormous amounts of heat. That warm water then opened up the ice plugged channels between the islands of northernmost Canada. If high pressure breaks down now the thick plugs of multi-year ice that used to block the channels won’t be there to impede the fresh water from draining out to the north Atlantic. The largest channels have a thin ice cover.

Arctic scientists fear that a large volume of the stored fresh water could be rapidly released, drastically impacting the northern hemisphere’s weather. http://earthobservatory.nasa.gov/blogs/fromthefield/category/beaufort-gyre-exploration/

    As I said back in my first blog entry, one of the key objectives of the expedition was to produce an up-to-date assessment of the freshwater content of the Beaufort Gyre. Based on a preliminary analysis of the data collected on this cruise, my colleagues reckon the total freshwater content of the Gyre could be at a record high. A chemical analysis of the ocean surface suggests that sea ice melt contributed around 20 percent of the fresh water mixed up within the surface waters, compared to around 80 percent from Canadian and Russian rivers flowing into the Arctic. The sea ice contribution was thought to be neutral a few decades ago, but the ice is now melting more than it’s growing, as we clearly witnessed, causing an imbalance. The wind circulation is also important in driving the ocean circulation that sucks in fresher surface waters into the Gyre (see an earlier blog of mine for more details).

    Why does this all matter? Well, some scientists posited that the Beaufort Gyre oscillates between periods of spinning up and sucking in freshwater, and spinning down and releasing fresh water. A kind of breathing, if you like. The Gyre has been spinning up and sucking in fresh water for a few decades now (2008 saw a big increase) and we keep waiting, with similarly bated breath, for this trend to reverse. If the Gyre does reverse (breathe out), the Arctic Ocean will likely dump a load of fresh water into the Atlantic Ocean (as we think it did in the 1970s), which could cause some big impacts on weather patterns across the Northern Hemisphere. We’re not expecting a scene out of The Day After Tomorrow, but we’re not entirely sure what could happen either.


This dark half of the Arctic year has been by far the warmest to date on record and storms have repeatedly slammed the sea ice to record lows while pulling in heat from both the Atlantic and Pacific oceans. If this stormy weather continues, the fresh water dome will break down and the fresh water rapidly drain towards the north Atlantic through the channels of the Canadian archipelago and through the Fram strait east of northern Greenland.

The weather forecast for the next 10 days by the European model is insane. Deep lows will pull massive amounts of heat into the Arctic, which will keep sea ice extent and volume at record low levels for the date and will work to spin down the currents that keep the dome fresh water in the Beaufort sea.


5 day ECMWF weather forecast shows storms entering the Arctic from both the Atlantic and Pacific. The winds will bring enormous amounts of atmospheric heat, taken from the Atlantic and Pacific oceans, into the Arctic.

The weather pattern developing in the Arctic is the pattern that has drained the fresh water form the Beaufort gyre in the past. Extremely deep lows are moving from the Atlantic into the Arctic. Low pressure is dominating the region from the Atlantic’s subarctic seas to the Arctic ocean. If this pattern continues through this winter, a volume of fresh water greater than lake Michigan could be set in motion towards the north Atlantic and the overturning circulation could stall when the light fresh water caps the Labrador sea. This could cause the Gulf Stream itself to slow while heat would build up in tropical oceans.

Extreme low pressure is forecast by the ECMWF model to cover the Arctic and north Atlantic in 7 days.

Scientists and Arctic observers are shocked by this year’s extraordinarily warm Arctic weather but the sudden release of fresh water to the Atlantic could cause a sudden shift to much colder winter weather towards the end of the decade. This is a very unpredictable situation, but Greenland ice cores show that rapid, extreme climate oscillations may be triggered by north Atlantic salinity cycles. http://www.atmosp.physics.utoronto.ca/~peltier/pubs_recent/W.R.%20Peltier%20and%20G.%20Vettoretti,%20Dansgaard%20Oeschger%20oscillation%20in%20a%20comprehensive%20climate%20model,%202014.pdf

We may be entering a period of extreme climate chaos.







FishOutofWater

  • ASIF Middle Class
  • Posts: 685
    • View Profile
  • Liked: 201
  • Likes Given: 88
I posted this at Dailykos a few days ago and finally found time to get the formatting to (mostly) work over here. My posts are image heavy so it's necessary to post them at a place that will keep on hosting the images. I post too many images to post them directly to the forum. The image attributions/credits are clearly stated at dailykos. Those attributions don't directly translate to the forum. I'm still working on how to post here.

jdallen

  • ASIF Governor
  • Posts: 2951
    • View Profile
  • Liked: 131
  • Likes Given: 154
I'm not convinced.

From my geology, I'm quite aware of fresh water release events which have significantly altered thermohaline circulation and changed current flow between the tropics and the arctic.

However, those events were tied to pretty massive releases of fresh water; in specific massive melt of the continental glaciers and in a few cases, catastrophic release of impounded fresh water in one go (e.g. the end of Glacial Lake Agassiz).

I think it's also pretty important to keep the volume of that lens in context - we're talking about thousands of KM3 vs 10's of millions of KM3 when we consider the arctic as a whole, and when examining that lens if dispersed, not much more than a meter of fresh water over all across the Arctic as a whole.

I'd also contrast that with the current increase in storminess and active surface flow - something which doesn't take place (as much) in ice covered regions.

Before buying into this, I think I want to see an awful lot more supporting data.
This space for Rent.

jai mitchell

  • ASIF Upper Class
  • Posts: 2004
    • View Profile
  • Liked: 48
  • Likes Given: 16
Haiku of Past Futures
My "burning embers"
are not tri-color bar graphs
+3C today

jdallen

  • ASIF Governor
  • Posts: 2951
    • View Profile
  • Liked: 131
  • Likes Given: 154
Still not convinced.   What the table shows is an increase of about 20,000KM3 overall in volume - which is still less than 2/100's of one percent of the total basin volume.  I'm far from convinced that will significantly slow down the Gulf Stream.
This space for Rent.

FishOutofWater

  • ASIF Middle Class
  • Posts: 685
    • View Profile
  • Liked: 201
  • Likes Given: 88
Except for the observation that this dark season's weather is perfect for breaking down the dome of relatively fresh water, none of this theory is mine. The Gulf Stream itself is largely wind driven but the overturning circulation is sensitive to surges of fresh water. In 2010 the Gulf Stream itself had a big slow down while the overturning circulation broke down for months. Warm water built up in the tropical Atlantic is spring 2010 when the Gulf Stream slowed. An intense hurricane season followed.

Altimetry shows the breakdown of the THC and the Gulf Stream in March 2010. High SSH levels built up in the tropical Atlantic while SSH was very low in the Atlantic north of Bermuda.

Melt water from Greenland may be one factor in the decline of the overturning circulation and a surge of Beaufort sea water may be another. Obviously winds and storminess also play a role.

jai mitchell

  • ASIF Upper Class
  • Posts: 2004
    • View Profile
  • Liked: 48
  • Likes Given: 16
I wasn't stating this as a critique of anyone else's post or I would have said so.  I was simply providing additional reference documents to allow you to see some other studies and what they have shown to be the amount of fresh water influx and outflows in the region.

Noticeably, the amounts they are talking about in all 3 papers are greater than the amount mentioned in your journal. 

By the way, I am a little surprised you still post at that "vox news" of the left website.  bunch of partisian hacks remaining there, with little to no interest in either A) reality or B) anything other than their own narrow personal interests.
Haiku of Past Futures
My "burning embers"
are not tri-color bar graphs
+3C today

ktonine

  • ASIF Citizen
  • Posts: 363
    • View Profile
  • Liked: 0
  • Likes Given: 0
FOoW - If you haven't already looked at Response of the Atlantic Ocean circulation to Greenland Ice Sheet melting in a strongly-eddying ocean model, you will find this bit interesting:
Quote
Lacking reliable dynamic projections, we apply an integrated freshwater flux of 0.1 Sv in our simulations [Stouffer et al., 2006; Gerdes et al., 2006]. Being an order of magnitude larger than the flux implied by the current mass deficit of the GrIS, this rate can be considered a worst case scenario if the GrIS were to undergo a catastrophic collapse. To put this value in perspective, freshwater discharge by the Amazon river is of the order of 0.2 Sv [Molinier et al., 1995], the armada of icebergs that entered the North Atlantic ocean during Heinrich Event 4 may have been equivalent to about 0.3 Sv [Roche et al., 2004], while the Lake Agassiz freshwater discharge (thought to have been responsible for the 8.2 kyr climate event) may have been equivalent to 0.17 Sv [Hijma and Cohen, 2010]. A substantial accumulation of fresh water in the Beaufort Gyre has recently been detected [Giles et al., 2012], representing enough fresh water to produce a flux equivalent to 0.1 Sv over a period of nearly 3 years, when the wind forcing that contains it eventually shifts.

Obviously the amount has increased since that 2012 paper and  I don't know if  0.1+ Sv over 3 years is enough to slow the AMOC down, but this does put some context around it.  It should also show that this is not something out of fantasy-land, but a possible result that needs  consideration.

FishOutofWater

  • ASIF Middle Class
  • Posts: 685
    • View Profile
  • Liked: 201
  • Likes Given: 88
Jai, I continue to post there because I have built up a readership. Many smart people who have backed away from the train wreck of the coverage of the recent election there continue to read environmental posts like mine. Over the next few years I expect environmental issues to be in the global spotlight. Trump is a global disaster and everyone with a conscience will need to come together to resist. Thanks to that web site I've met up and worked a bit with DocDawg, real name Bill Busa, who is a national academy of sciences member involved in fighting for better governance in North Carolina.  I'm living mostly in a farm town best known for its Smithfield plant that ships ham, bacon and pork chops to cities across America and China. We have lots of pig farms nearby.

I have started posting here because I need better technical discussion and constructive criticism of my posts and because we need to pick up the slack for Neven so he can enjoy life more.

The criticism here is already helping me dig in deeper to understand how the changes in the Arctic are interacting with global weather. What's really blowing my mind is the stratospheric connection to the oceans and how it stratospheric interactions are affecting the weather in both the Arctic and  Antarctica.

Jim Hunt

  • ASIF Governor
  • Posts: 4051
    • View Profile
    • The Arctic sea ice Great White Con
  • Liked: 131
  • Likes Given: 21
I've been following Proshutinsky et al. on this for years. Quoting Alek Petty's recent article:

Quote
If the Gyre does reverse (breathe out), the Arctic Ocean will likely dump a load of fresh water into the Atlantic Ocean (as we think it did in the 1970s), which could cause some big impacts on weather patterns across the Northern Hemisphere. We’re not expecting a scene out of The Day After Tomorrow, but we’re not entirely sure what could happen either.

An old AMOC article of mine:

http://econnexus.org/the-day-after-tomorrow-coming-soon/

Quoting Stefan Rahmstorf:

Quote
A major change in ocean circulation is a risk with serious and partly unpredictable consequences, which we should avoid. And even without events like ocean circulation changes, climate change is serious enough to demand decisive action.

I also find the film quite successful in giving a flavour of the world of climate science – I did recognise our world, what the work places look like, the pictures on the wall, how the climatologists talk, etc.
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

FishOutofWater

  • ASIF Middle Class
  • Posts: 685
    • View Profile
  • Liked: 201
  • Likes Given: 88
Yes, Jim, that Alec Petty quote is buried deep in my post. Given the political madness in the U.S. I didn't want to highlight his name at a Democratic party oriented web site.

Alec Petty's personal blog is gone. His posts at NASA's earth observatory site are still up.

I once worked for the Feds in the U.S. so may paranoia runs deep.

I read your blog pretty regularly. I enjoy it. I also get a good laugh watching your surf videos. I used to body surf in Hawaii so I, too, have taken abuse from many clean up sets.

jai mitchell

  • ASIF Upper Class
  • Posts: 2004
    • View Profile
  • Liked: 48
  • Likes Given: 16
The criticism here is already helping me dig in deeper to understand how the changes in the Arctic are interacting with global weather. What's really blowing my mind is the stratospheric connection to the oceans and how it stratospheric interactions are affecting the weather in both the Arctic and  Antarctica.

what is blowing my mind is the indication that Tropospheric heat and water vapor is radically changing the teleconnecting global atmospheric circulation patterns, in absence of major structural changes in the Stratospheric circulations.  If any stratospheric influence is to be found it is directly attributable to the minor reductions in Aerosol emissions from SE Asia in the first half of 2016.

I have been a fan of your work. 

Haiku of Past Futures
My "burning embers"
are not tri-color bar graphs
+3C today

etienne

  • ASIF Middle Class
  • Posts: 682
    • View Profile
    • About energy
  • Liked: 30
  • Likes Given: 1
Well, I am not a specialist, but what surprises me in this context is that on one side, there is a slowing down of the Gulf Stream, and on the other side, we have record high sea surface temperature. I have no opinion on on why this happens.

Regarding the link provided by

An old AMOC article of mine:

http://econnexus.org/the-day-after-tomorrow-coming-soon/


if you follow the link, there is the statement that :
"02:20 – 90% of the people living in the Northern Hemisphere above 50° north are living in Europe and in Russia, so if you change the climate then these people will have no more crops to live on and they will have to move, so there will be a gigantic migration of people when the climate is changing here. That's why we should be interested in the stability of our local climate."

Well, righ now, we have record heating in Siberia, and people are rather going the other way, from south to north because of lack of rain and wars that could be related to the water issue.

I don't mean that the concept is wrong, just that it is more complicated than just what is presented here.

Best regards,

Etienne

FishOutofWater

  • ASIF Middle Class
  • Posts: 685
    • View Profile
  • Liked: 201
  • Likes Given: 88
Etienne, based on paleoclimate studies, I suspect that we will see wild oscillations in weather as we go through multiple years of warming followed by episodes of cooling tied to slow downs in the thermohaline circulation. I'm thinking we will see something like D/O cycles. One of the things we need to do to try to understand what's happening now is to understand what happened when things were changing rapidly in the relatively recent geologic past. D/O cycles are relevant, in my opinion.

Clearly the climate models are having trouble resolving the fine details of Arctic climate change. That doesn't mean that their large scale predictions are wrong. The averages of the increasingly extreme weather may be captured by the models while they miss the extreme variability.