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Polar Amplification vs a Godzilla El Nino — Is the Pacific Storm Track Being Shoved North by Arctic Warming?

It’s an El Nino year. One of the top three strongest El Ninos on record. The strongest by some NOAA measures. And we are certainly feeling its effects all over the world. From severe droughts in Southeast Asia, Africa, and South America, to Flooding in the Central and Eastern US, Southern Brazil, and India, these impacts, this year and last, have been extreme and wide-ranging. During recent days, Peru and Chile saw enormous ocean waves and high tides swamping coastlines. Record flooding and wave height events for some regions. All impacts related to both this powerful El Nino and the overall influence of human-forced warming by more than 1 C above 1880s temperatures on the whole of the hydrological cycle.

Amped up by a global warming related 7 percent increase in atmospheric water vapor (and a related increase in evaporation and precipitation over the Earth’s surface), many of these El Nino related impacts have followed a roughly expected pattern (you can learn more about typical El Nino patterns and links to climate change related forcings in this excellent video by Dr Kevin Trenberth here). However, so far, some of the predicted kinds of events you’d typically see during a strong El Nino have not yet emerged. A circumstance that may also be related to the ongoing human-forced warming of the globe.

Storm Track Not Making it Far Enough South

Particularly, there has been an absence of powerful storms running in over Southern California then surging on into Arizona, New Mexico and West Texas. During strong El Nino events, heat and moisture bleeding off the super-warmed Equator have typically fed powerful storms racing across the Pacific. These storms have tended to engulf the entire US Pacific Coast from San Diego through to Seattle. However, much of the storm energy is often directed further south toward Central and Southern California.

Ridiculously Resilient Ridge Returns

(A massive Pacific storm being warded off by high pressure systems over the US West Coast on Tuesday, January 26th. Image source: Earth Nullschool.)

These storms tend to run over regions that are typically much drier. So strong El Ninos of the past have often generated abnormal and memorable storms and rains. But this year there has been, mostly, an abscense of such events. Storms have slammed into Northern California, Oregon, been deflected back into the coasts of Canada and Alaska, or even been bottled up near the Aleutian Island Chain.

But today, a high pressure cell dominates the western US, warding off a powerful storm system. The storm, howling just south of Alaska and pushing out average 60 foot wave heights and hurricane force winds across the Pacific, is predicted to rebound toward Alaska where it will become bottled up in the Bering sea and push above freezing temperatures into the Arctic Beaufort Sea during Winter. The storms and rains will steer far away from Southern California and even much of California altogether.

Rainfall Patterns Have Tended Toward the North, Contrary to NOAA’s Seasonal Predictions

 

NOAA Precipitation

(NOAA precipitation quantities prediction for the coming week is indicative a continued northward shift of the Pacific Storm track. Image source: NOAA.)

It’s a pattern more reminiscent of some strange ridiculously resilient ridge (RRR) than that of a strong El Nino. And though storms later this week are again predicted to slam into the Northwest and weekly rainfall totals are expected to rise to near 1 inch for parts of Southern California, the path of these storms and related moisture flows are quite a bit further north than one would expect for a year in which strong El Nino was the dominant feature.

The moisture flow, instead, so far has tended northward across the upper and central tiers of the US even as the El Nino related moisture bleed toward the Gulf and East Coasts has remained quite intense. Such observed weather is both contrary to what we’ve tended to know about Strong El Nino and to NOAA’s seasonal forecasts which had predicted much more rain for the southwest than what we’ve seen so far.

Seasonal Outlook NOAA

(NOAA three month outlook is more in line with traditional strong El Nino forecasts bringing strong storms in through the southwestern US. We currently do not see a prevalence of that particular pattern. Image source: NOAA’s Climate Prediction Center.)

Polar Warming + Hot Blob Tugging the Storm Track Northward?

Since weather patterns related to El Nino are an aspect of global atmospheric dynamics — teleconnections between the influence of an excess of hot air and heavy rainfall at the Equator and of large scale atmospheric wave patterns downstream, you have to wonder if there isn’t some kind of influence competing with El Nino on a global scale. One with enough oomph to nudge the Pacific Storm Track northward.

Hot Blob Pacific Northwest

(The Hot Blob is still a dominant feature of ocean waters in the Pacific Northwest. Is its influence helping to pull the Pacific Storm Track northward during a strong El Nino year? Image source: Earth Nullschool.)

The first likely suspect is the pool of still much warmer than normal sea surface temperatures lurking off the US West Coast. Though somewhat diminished from their peak during 2014 and 2015, the waters in the hot blob off California, Oregon, Washington, Canada and Alaska are still in the range of 1 to 3 C above average. A very large region of significantly warmer than normal ocean surfaces that wasn’t present during the 1982-83 and 1997-1998 super El Ninos. And much of the warmest anomalies are now centered much further to the north along the coast of Alaska.

But the second potential player is likely even more significant. And that would be an ongoing and extreme warming of the northern polar region. Heating at the Pole generates less thermal gradient between the higher Latitudes and the Equator. And such a lessened gradient would tend to impact the strength of the circumpolar winds that drive weather systems and storm tracks. In particular, the overall warming of the globe would tend to pull these storm tracks northward even as the loss of thermal gradient would tend to enhance wave patterns in the Jet Stream.

 

Polar Amplification January 26

(Polar Amplification shown as very intense in the January 26 Climate Reanalyzer graphic. Is Polar Amplification helping to shove the Pacific Storm Track northward even during a record strong El Nino year? If so, it’s bad news for long term moisture levels in the US Southwest. Image source: Climate Reanalyzer.)

Perhaps also specifically related to this ongoing polar amplification, we find that two warm slots — one over the Barents and far North Atlantic east of Greenland and another over the Bering — have tended to develop during recent Winter years. These slots have often served as staging areas for warm air invasions of the Arctic. But what they also represent are regions of water that have been freshly liberated from their sea ice coverings. As such, these vast regions of water serve as heat transport and ventilation zones. And all this extra heat energy may be sucking the related North Atlantic and North Pacific Storm tracks into what may well be described as an oceanic and atmospheric trap.

If such a situation where the case, we’d tend to see a dipole of warm east, cold west in the storm trap regions. And that’s exactly what we’ve seen more and more of with Greenland and Siberia serving as the backdrops to reinforce this tendency. Thus setting up the stage for cold air slots cutting through Northeast Siberia and Northeast Canada and warm, wet air slots over Alaska and the UK.

The question to be asked is, then, are these new influences related to human-forced warming also now doing battle with El Nino for control over the Pacific Storm Track? And has that influence increased enough to dramatically nudge that track northward? We may find the answer to that question in what happens to the direction of powerful Pacific Storms over the next few months. But early indications seem to be that polar warming and the related hot blob may have thrown a wrench in the kinds of El Nino storms that we’ve been used to.

Links:

El Nino Related Waves, Floods Strike Chile

Dr Kevin Trenberth on El Nino and Climate Change

Earth Nullschool

Climate Reanalyzer

NOAA’s Climate Prediction Center

NOAA

The United States Drought Monitor

Hat Tip to Colorado Bob

Hat Tip to DT Lange

Hat Tip to Andy in San Diego

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Hothouse Monsters Clash: Godzilla El Nino Pummels Pacific’s Hot Blob

Two climate change spawned monsters are duking it out over thousands of miles of Pacific Ocean waters. And in a human heated world its an epic battle between these two warming fueled atmospheric and oceanic goliaths — the Godzilla El Nino versus the Pacific Ocean’s Hot Blob.

*  *  *  *  *

Ridiculously Resilient Ridge. RRR. Blocking high pressure system. All names given to a sprawling heat dome that has plagued the U.S. West Coast for the better part of two years running. It’s a weather system largely responsible for the California drought — the worst in at least 1200 years. A weather system implicated in an extraordinarily intense outbreak of wildfires across the North American West from Alaska through British Columbia and all along the US West Coast — including within the usually moist rain forests of Washington and Oregon.

image

(The RRR is shrinking and increasingly besieged by storms. A sign that the El Nino related Pacific Storm track intensification is beginning to assert. Image source: Earth Nullschool.)

It’s a system connected to a climate change-enforced melting of Arctic sea ice and a similarly forced warming of the Northeastern Pacific Sea surface far above typical temperatures (see here, here, and here). An unprecedented and extreme heating of waters into a ‘Hot Blob’ stretching for thousands of miles. A related drying of airs. Oceanic and atmospheric heat energy generating an implacable atmospheric bully. A high pressure system so powerful it typically flung Pacific Ocean storms far off course — as far north as the High Arctic.

But now the RRR is starting to weaken. Its great northward extending ridge has retreated from Alaska. Intense storms exploding out from a system that is likely to rival the strongest El Nino on record (1997-1998) are now surrounding the ridge, nibbling away at its edges, cooling the waters of the hot blob through Ekman pumping, and raging on through Alaska and the Pacific Northwest.

image

(Storm-based upwelling is starting to cool Northeastern Pacific Ocean waters in a region that has been dominated by the Hot Blob during recent years. A condition that is undermining some of the RRR’s support. El Nino based storm generation to the south will likely continue to aim blows at this oceanic heat base. Image source: Earth Nullschool.)

It’s early sign of RRR collapse. That the Hot Blob is starting to fail. With some of the precursors to likely far more intense Fall and Winter storms starting to get caught up into its spiraling decline. And as sea surface temperature anomalies are likely to hit 2.0 to 2.3 C above average in the Niño 3.4 zone in this week’s NOAA El Niño report, more RRR-challenging storms are likely on the way.

As Ricky Rood over at Weather Underground said this week it’s Godzilla vs the Blob. And Godzilla, at this point, appears to have the upper hand. And once the Blob goes down there’s nothing to keep what are likely to be some seriously epic storms slamming into the west coast of North America this Fall and Winter. But according to recent science, there’s a high risk that the Blob will creep on back as the Godzilla El Nino retreats during mid to late 2016. And for the West Coast that means high risk of a pretty vicious cycle of drought to flood to drought. A dangerous weather pattern intrinsically related to human-forced climate change.

Links:

Earth Nullschool

Godzilla Versus the Blob

California Drought Worst in 1200 Years

Climatologist Who Predicted California Drought Says it May Soon be Even More Dire

Dr. Jennifer Francis: Arctic Sea Ice, the Jet Stream and Climate Change

Hat Tip to Colorado Bob

California Experiencing Driest Year on Record, Epic Drought to Persist or Intensify Through Summer, Godzilla El Nino Waits in the Wings

8.83 inches. That’s the total average precipitation accumulation for the state of California so far for the first four months of this year. Out of the entire climate record, this paltry accumulation is less than that received during any similar period of any year since 1895.

Overall, rainfall totals throughout the state remained below 26 percent of typical levels for this time of year. And with California entering its third year of drought, the state would have to receive an average of 53 inches between now and October, more than 10 inches of rainfall each month, to break the current and very extreme ongoing drought.

May 6 drought monitor

(Drought monitor color graphic of California drought as of May 6. Tan = moderate drought. Orange = severe drought. Red = extreme drought. Dark Red = exceptional drought. Image source: Drought Monitor.)

As of late April, the drought had expanded to cover every corner of the state leaving not an inch of this critical agricultural region untouched. Drought continued to intensify, bringing with it water stress, cracked soil, crashing reservoirs and heavy strains to farms, businesses, cities and individuals. By May 6, fully 77 percent of California stifled under severe or extreme drought conditions.

The drought has become so severe that water-strapped cities like Santa Cruz have resorted to the most dire measures, including rationing, to husband dwindling water supplies. Last week, the city, which depends on some of the most vulnerable and thinly-stretched water resources in the state, announced a number of severe fines to water consumers exceeding assigned usage levels. The fines could quickly double, triple, or even quadruple water costs for any non-farm water consumer within the city.

Across the State, various desperate water conservation regimes have been put in place with the Federal Government announcing earlier this year that it would be forced to stop water allocations to farmers in an unprecedented move to stave off further declines in stores.

US Seasonal Drought Outlook

(US Seasonal Drought Outlook. Image source: CPC.)

Unfortunately, the persistent high pressure blocking pattern off the US West Coast, which has hovered in the same region for more than a year, remains in place even as it continues to deflect rain-bearing storms north toward the Washington and Canadian coasts.

This pattern — arising from a set of abnormal atmospheric conditions including added heating through human-caused warming and a Jet Stream that has the tendency to become stuck more and more often as sea ice erodes — results in a high likelihood that drought will remain or intensify for California and much of the US Southwest throughout this summer.

Climate Prediction Center analysis, shown above, projects that the current California drought will persist or worsen for the entire state through at least July 31rst. If relief does come, it will arrive many months from now. For the most likely chance for a change in the weather doesn’t appear until fall and winter of 2014. And this potential brings with it the risk for a radical switch to yet another damaging climate extreme.

Hoping For El Nino is Like Praying to Godzilla

Yesterday’s report from NOAA indicating a near 80 percent chance of El Nino by the end of this year provided some hope for additional rainfall after what is expected to be a very dry and difficult summer. But given current atmospheric conditions, the El Nino event would have to be in the moderate-to-strong range to both overcome what is a demonically persistent blocking pattern and to deliver enough moisture to make up the severe rainfall deficit. Anything less would be too weak to cure the current drought. But something stronger may well kill the patient.

Unfortunately, there remains a substantial risk that the 2014-2015 El Nino event could be a Godzilla of a thing — a monstrous outburst of the extreme ocean heat storage of the past 16 years that Dr. Kevin Trenberth has warned could well come back to haunt us. A record high ocean heat content that is out there, lurking in the Pacific Ocean even now. And it’s the potential that this heat will hit the surface with a severity rivaling or even exceeding the epic 1998 event that should well be cause for a different kind of concern.

ohc-2013

(Ocean heat content through 2013. Image source: Reanalysis of Global Ocean Heat Content.)

In such an instance, the onrush of heavy rains would be less a relief and more a switch from extreme drought to extreme flood. During the 1998 event more than 20 California counties were declared disaster areas due to the sudden deluge. But with human warming amping up the hydrological cycle by more than 6% and with such a large and vicious store of ocean heat waiting to be released, a severe El Nino at this stage might look more like an Arkstorm — an event which could dump many feet of rain over a period of weeks.

On the other hand, if the El Nino fizzles into only a minor event and that massive ocean heat store decides to lay in wait for another year or two or three, California is much more likely to remain locked in a continued multi-year dry pattern. So the best California could hope for is to thread an El Nino needle and receive a just-right moderate to strong El Nino. But with the current climate regime favoring extremes, the possibility for such a just-right occurrence is quite a bit lower than either the Godzilla or the fizzle.

In any case, both added heat and dryness are set to intensify over coming years and decades for California. This ongoing ratcheting is the direct result of human-caused climate change. A result that will either be bad or terrible depending on whether or not we decide to rapidly reduce and eliminate our greenhouse gas emissions.

Links:

Climate Outlook for Central California

Drought Monitor

CPC

Santa Cruz Rations Water

Farmers to Receive No Central Valley Water This Year From Feds

Dangerous Progress Toward Strong El Nino Continues

Reanalysis of Global Ocean Heat Content

 

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