Bermuda High No More — Global Warming Shoves North Atlantic Anticyclone Toward Azores

The semi-permanent weather patterns are all out of whack. The Aleutians Low has been shoved into Alaska and the Beaufort. The Pacific California High has shifted north and west to dominate the region previously claimed by the Aleutians Low. And the Bermuda High — a feature famous for directing tropical cyclones northward along the Atlantic Seaboard has packed its bags and fled north and east.

During the late summers of more stable climates, a strong high pressure system tended to form over the region of Bermuda. The high swept warm, moist air up off the Atlantic Ocean and over the Eastern Seaboard of the United States. The high was also a reliable governor of the movements of tropical cyclones — with the position of the high critical in determining whether these powerful summer storms would make landfall or rocket out to sea.

But this August, the Bermuda High is nowhere to be seen. Instead, it’s shifted more toward mid and north Ocean — closer to the Azores and the Flemish Cap.


(The Bermuda High can now also be counted among the growing number of climate change refugees as it emigrates to the Azores and the higher Latitudes of the North Atlantic. Image source: Earth Nullschool.)

In the above image, provided by Earth Nullschool, white denotes areas of high pressure and purple-to-red denotes areas of low pressure. The green circle in the image marks the position of the North Atlantic High in today’s GFS summary map. Note that the high is shifted more than 1,000 miles to the east and north. It sits at the base of a ridge that stretches well north of the Flemish Cap and then extends eastward to just south of Britain, Scotland and Ireland. Near Iceland, a powerful cyclone rages. A fickle storm that alternatively sets its sights along an arc from England to Svalbard.

How Human-Caused Warming Shoves the Bermuda High Northward

A semi-permanent high pressure system north of the Azores and a very stormy North Atlantic in the triangle between Greenland, Svalbard and England is not remotely a normal summer weather pattern. It’s instead a feature of a number of new ocean and atmospheric dynamics that are the upshot of human-caused climate change.

As equatorial heat embodied by the Hadley Cell expands outward from the lower Latitudes, the oceanic highs, including the Bermuda High, are shoved northward. This motion tends to also shift weather tracks into higher Latitude boundaries even as it, at first, enhances waviness in the Jet Stream. Near North America, we can see this dramatic weather alteration in the form of the Ridiculously Resilient Ridge over the Pacific and the Terribly Tenacious Trough over the Eastern Seaboard.

A second feature that influences the displacement of the North Atlantic High is the expansion of a cool pool of water to the south and east of Greenland. This cool pool is an upshot of the ongoing melt of the Great Greenland ice sheet. As fresh water spills out from Greenland’s glaciers it cuts off the northward propagation of the Gulf Stream even as it prevents bottom water formation. This shutting down of ocean circulation causes heat to build further south along the Eastern Seaboard of the United States and in the Caribbean and Gulf of Mexico. The lack of south to north heat transport combines with the expanding fresh water cap to prevent ocean heat ventilation at the surface in the North Atlantic. As a result, we see an expanding pool of cool water in this zone. A signature feature of both human caused climate change and of glacial melt in Greenland.


(Earth Nullschool temperature anomaly map focused in on the North Atlantic with near -5 C readings in an uncanny and freakish cool pool there. This is the mirror opposite of the Hot Blob in the Northeast Pacific. And, eerily enough, it is also a feature of overall global warming. Image source: Earth Nullschool.)

During recent years, we have seen more and more of this cool pool formation as both the Gulf Stream and bottom water formation in the North Atlantic slowed down due to fresh water outflows from Greenland. It’s an oceanic cool pool that forms a kind of atmospheric slot for the Bermuda High to slip north through. It also generates an unstable boundary zone between hot and cold waters and airs — a mechanism that generates very high potential energies for powerful storms cycling in a rough arc around Greenland (climate change driven storms of this kind were the subject of a recent paper by Dr. James Hansen.)

As glacial outflows from Greenland expand due to a continued forced economic dependence on fossil fuels and the dumping of their toxic, heat-trapping emissions into the atmosphere, we are likely to see the Bermuda High continue to shift north. It’s the first of many features that will tend to produce powerful atmospheric bomb-type storms in a great zone within the North Atlantic. Storms of an intensity we likely haven’t seen through all the 10,000 year period of the Holocene.

It is for this reason that the shift of the Bermuda High north and east should be viewed as an ominous atmospheric move. One that is preparatory to far worse weather to come — during a time when the old Bermuda High will, perhaps, be viewed with a kind of fond nostalgia. A gentler weather feature of a once far kinder climate.


Semi-Permanent Weather Patterns

Earth Nullschool

Global Forecast System Model

Hadley Cell

Ridiculously Resilient Ridge

Terribly Tenacious Trough

Warning From Scientists: Stop Fossil Fuel Burning or Age of Storms, Rapid Sea Level Rise is Coming Soon

Leave a comment


  1. Reblogged this on GarryRogers Nature Conservation and Science Fiction (#EcoSciFi) and commented:
    Please read the comments on this and other posts for added information and interpretation.

  2. Here at the Our Heads Are in the Sand Institute, it’s even better than we thought.

  3. climatehawk1

     /  August 10, 2015

    Tweet scheduled.

  4. One concern might be the possibility that at some point the existing atmospheric circulation system breaks down and restructures on a much larger scale, perhaps with less circulation cells (having 3 in each hemisphere currently). If possible, that would transform the world in human terms.

  5. Thank you Robert for this excellent new article, which has educated me.
    I was beginning to think your younger readers might be emboldened to start posting inspirational One Direction videos, but this has not been the case.

  6. Why is the water warmer than normal around Greenland if this year’s cool pool is caused by glacial melting around Greenland? Last winter was extremely stormy around Greenland and cold dense water penetrated the 1000m water layer in the Labrador sea. There was a big impact in 2013 after the big Greenland melt in the summer of 2012. The Gulf Stream slowed in fall 2012 and winter 2013 and the overturning circulation in the Labrador sea pretty much shut down. However, last winter and this summer is very different from 2012-2013. Right now, the hot tropical Pacific is driving a stronger than normal summer jet stream across the Atlantic.

    If this pattern is associated with cold fresh water not sinking it would be related to the stronger than normal northwest wind and water flow over the past year over the Labrador sea. The main source of the water would be the Arctic ocean and the Canadian archipelago region. Greenland was cooler than normal until late June this year.

    Yes, the warming of the north Atlantic has been shown by recent papers to cause the center of the high to move northeastward in climate models. However, this summers intense storm track across the north Atlantic along the boundary between the warm water and the cool pool “suggests” a cause of the cool pool – upwelling caused by the storms.

    • The cool pool has been pervasive since the large outflow of glacial water in 2012. It is in the zone climate models indicate for cool pool development due to failure of bottom water formation and Gulf Stream weakening. Climate models do not indicate near Greenland cooling to be so strong instead shifting the zone to the North Atlantic where the Gulf Stream and AMOC fail.

      In addition, the high in the North Atlantic is not heat dome based. Instead it is baroclynic — or dipole based.

  7. “The Aleutians Low has been shoved into Alaska and the Beaufort. The Pacific California High has shifted north and west to dominate the region previously claimed by the Aleutians Low. And the Bermuda High…”
    Good synopsis, Robert.
    There is so much dysfunction to report on.
    Somebody has to do it in its many aspects.

    • Cheers, DT. The Bermuda High shift is something Hansen predicts as a feature of ‘Storms’ in the North Atlantic. Eventually, according to the Models Hansen developed, the High backs up over the cold pool and we get these powerful storms screaming around it.

      • Cheers to you too, Robert.
        He (JH) sure seems to on top of theses very important elements of our possible survival.

  8. labmonkey2

     /  August 10, 2015

    And as everything in the climate world is connected, what impact will this have on the El Nino for this fall as these systems break down? Will we in the SoCal region see any potential relief from our extended drought? Predictions so far are still uncertain as to location and impact, but my ‘monkey sense’ from the usual May grey and June gloom inland extent this year (and we’re still getting some in August!) tells me that we may be in for a soaker.

    • El Nino appears to be setting up to fire the storm track north toward Alaska and the Arctic, south toward the US Southeast and then dump all that energy into the devastating firing range that the North Atlantic is becoming. If this happens, the RRR is an El Nino teleconnection event. The TTT is as well. Oh, and polar amplification this winter looks really, really bad.

      Such a forecast is preliminary. But unless the Pacific hot blob starts cooling down soon, I don’t think the storm track has much of a chance to over-ride. Models show the hot blob remaining. That’s its own brand of weirding trouble.

  9. Jeremy

     /  August 10, 2015

    Great story from Dave.

    The utter madness of CA farmers drilling deeper and deeper for water as the drought bites.

  10. – PNW “emergency closure’.
    – One more example of the atmospheric magnifier over the PNW inflicting once unimaginable cruelties.
    These horrid things we are inflicting on nature and wildlife are worse than torture — much worse, and beyond cruelty.
    – This ’emergency’ is not part of a ‘drought’ cycle — this is a human fueled climate shift.
    – Everyone here should reinforce this certainty in reply to media and government alerts, etc.

    ‘Emergency closure of recreational fishing in most Olympic National Park rivers and stream begins Monday’


    To protect fish during the ongoing severe drought conditions, an emergency closure of recreational fishing will be enacted on Monday, Aug. 10, at 12:01 a.m. on most rivers and streams within Olympic National Park.

    Current conditions have made Pacific salmon, steelhead and bulltrout exceptionally vulnerable because of low stream flows and high water temperatures.

    • – There are so few butterflies alive at this time. It’s pathetic.
      – Media watch tip: the lede [sic] sentence about 1995 is irrelevant. It serves only to muddy the thrust of the main story. This sort of thing happens everyday in media/weather reporting.

      ‘Widespread butterfly extinctions could hit the U.K. as early as 2050’

      In 1995, the United Kingdom experienced one of its worst droughts in more than 200 years, causing some populations of butterflies to plummet. With climate change expected to cause more frequent severe droughts particularly in the southern United Kingdom, people are increasingly worried about the region’s drought-sensitive butterflies. Now, scientists have found that widespread regional extinctions of these insects could occur as early as 2050.

      “The prognosis is quite bleak,” says Tom Oliver, a co-author of the paper and an ecological modeler at the National Environment Research Council’s Centre for Ecology & Hydrology in Wallingford, England.

      Large skipper butterfly (Ochlodes sylvanus) Tim Melling

  11. James Burton

     /  August 10, 2015

    Picture in the Daily Mail today, shows a car in Italy with the plastic back bumper piece and side trim melted away,down to the ground , from the 100F and above heat wave. The Sahara moving into Italy?

  12. Colorado
    Durango copes with ‘orange nastiness’ of toxic sludge river pollution

    The Animas River in Colorado now glows orange after 3m gallons of toxins spilled in from a nearby gold mine, leaving the small community devastated…

    Discoloration of the Animas River can be seen as it flows adjacent to Durango high school in the heart of Durango, Colorado. Photograph: Jeremy Wade Shockley for the Guardian

  13. Now I am wondering what will happen to the future hurricanes in the North Atlantic. Maybe they’ll just meander, except for those caught by the Azores / Flanders Cap High and cartwheeled into the Svalbards and the UK.

    Not to mention Ireland.

  14. Re: action: “Later” is officially over”—Thomas Friedman a few minutes ago at the Areday conference that just began today. They’re live-streaming it.

  15. entropicman

     /  August 10, 2015

    Off topic, but is this Animas River pollution going to end up in Lake Mead?

    • Robert in New Orleans

       /  August 11, 2015

      The effluent is currently in the San Juan River which dumps into Lake Powell and then it will travel down the Colorado River through the Grand Canyon and then into Lake Mead where Las Vegas gets it’s drinking water from.

  16. Seems like humanity has to come to grips that, due primarily to increased heat energy, our climatic system is undergoing a change of state. Perhaps similar to how Cymatics changes patterns as frequency increases. (see gif below)

    If this level of change happened on Jupiter, we’d see the great eye of Jupiter shifting or morphing dramatically – along with all Jupiter’s other weather features. It’s so profoundly impactful what’s happening to our preciously finely tuned life-supporting spaceship. It’s wake up time humanity!

  17. Capitalism, unrestrained by the requirements of Planetary life support systems, is guaranteed mutually assured destruction. That is the obvious end game when money becomes sacrosanct. Socially enabled capitalism is clearly a failed paradigm. Help end tax funded pollution of the commons for starters.

    • hear hear! stop funding destruction! And reward generative solutions by shifting value(money) so that it couples directly to indicators that positively affect our interconnected holocene-life-support systems. It is no longer in our enlightened self interest to pursue capitalism.

  18. labmonkey2

     /  August 10, 2015

    New milestone in AK for acres burned so far this season – is now >5 million. And if the models are accurate in predicting the El Nino impact to the PNW more than the SNW, this will be a disaster. No more Ice Road Truckers – will be Mud Road Truckers.

  19. The paper’s only been out for a few days and already its predictions are beginning to be fulfilled. Had Hansen submitted this to peer review, it may have become obsolete the day it’s released!

  20. Apneaman

     /  August 11, 2015

    Hey dt

    Ozone pollution becoming a global, rather than local, problem

  21. johnm33

     /  August 11, 2015

    I wonder how much of the north Atlantic cold anomoly is down to the flow of less saline water through the archipelago, the hycom cice site 12months sss gif is only going back to may for me so.
    If you think it’s worth your time i’d like your take on the possible implications of a switch to a single hadley cell in the northern hemisphere.

    • These are good questions, John. Ones I’d have to dig into a bit deeper to find specific answers. In the larger trends we have AMOC weakening, AMO flip, Gulf Stream strength weakening, and increased melt outflows from Greenland. The cool pool is developing as climate models suggested but, as with many things, somewhat earlier than expected. Its intensity is not yet in the range of a truly extreme event. But it has flipped the North Atlantic into a different state — one that definitely favors more North Atlantic storms and puts England in the Bull’s Eye.

      The question for me right now is does this thing tend to flicker a bit for the next decade or so, or are we now on the faster track to a Storms type condition.

      The question regarding Hadley Cells is definitely something to consider. And it appears to me that an uneven expansion in the Hadley Cells over some regions are ripping the Walker Cell to bits.

      So, yeah, for me at least there are some things that I just have to keep out there in the unknown category. The atmospheric machinery, to my eye, is really being gutted and that makes it hard to determine where every piece will fall. I guess in this case we have limited meta analysis and limited models and we do our best with that.

  22. Johnny

     /  August 28, 2015

    Since the Bermuda high has moved further up to the northern part of the Atlantic doesn’t this make the Florida coast more vulnerable to being hit by tropical storms and hurricanes? It would seem plausible without the clockwise high pulling the tropical systems off into the northeastern Atlantic that this will increase the danger to the entire east coast.

    • The retreat would tend to make FL and the Gulf more vulnerable. But it also generates a new storm track that draws Newfoundland, Maine, and sometimes Greenland into the firing line. Right now, we do have a weak Bermuda high reasserting. But it’s not at typical strength which could be one reason why the models are so muddled.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: