Potential For El Nino Spikes As Record Pacific Ocean Heat Content Continues to Emerge

17 April, 2014

(Very powerful Kelvin Wave still moving eastward even as it begins to sink in off the coast of South America. Image source: NOAA.)

Likelihood for a significant El Nino later this year continued to increase as the most powerful Kelvin Wave on record continued its progress into the Eastern Equatorial Pacific. According NOAA’s recent April 13 assessment, the massive slug of anomalously hot Pacific subsurface waters continued to surge eastward, to deepen the 20 C isotherm and to spread out on or just below the surface.

NOAA’s most recent CPC report finds, in a bald refutation to assertions by climate change deniers, that:

A significant downwelling oceanic Kelvin wave that was initiated in January greatly increased the oceanic heat content to the largest March value in the historical record back to 1979 and produced large positive subsurface temperature anomalies across the central and eastern Pacific.

Extraordinary temperature departures in the range of 4-6 C above average stretched from a zone from 180 West Longitude to 80 West Longitude and ranged in depth from 30 to 70 meters. This very large zone of above average heat shattered global records even as it slid into position to begin re-delivering that excess to the atmosphere.

Perhaps more importantly, the nose of this wave of far warmer than normal water had begun to sag, pushing the 20 C isotherm deeper into the Eastern Pacific even as cooler water from the depths began to punch into the tail of the record hot Kelvin Wave, raising the 20 C isotherm in the Western Pacific. This downwelling force of a monster Kelvin wave appears to just now be initiating the start to a global weather-altering El Nino.

Hot Water Downwelling, Weakening Trade Winds

In the East, from 12 February to 13 April, the 20 C isotherm had plunged from about 25 meters below to around 100 meters of depth. During the same period, the isotherm from about 150 East Longitude to 170 West had risen from about 210 meters to 170 meters. At the subsurface, a continued rising of the isotherm in the West and its continued fall in the East would complete the transfer of warm waters across the Pacific and open the flood gates to the start of what could be an extraordinarily strong El Nino event as what is now a record Pacific Ocean heat content starts bleeding back to the atmosphere.

(20 C isotherm continues to rise in the Western Pacific [left side of graph] even as it rises in the East [right side]. Image source: NOAA.)

On the surface, trade wind weakening and reversals continued with a significant, though milder than those seen in January and February, backflow emerging in early April east of the Solomon Islands and coinciding with rather weak trade winds across the Equatorial Pacific. Such conditions continued to provide surface impetus to transfer warm waters across the Pacific even as record subsurface heat continued its transition eastward.

Chances for El Nino Rise

Accordingly, predictive forecasts both by NOAA and Australia’s Bureau of Meteorology are showing increasing potentials that El Nino will emerge. NOAA’s forecast now indicates that the chance for El Nino has jumped to over 50% by this summer and to 66% by the end of the year. Australia’s forecast is now showing a greater than 70% chance of El Nino over the same period.

In addition, El Nino type influences are already beginning to appear in world weather systems. A recent report by Dr. Simon Wang found that precursor El Nino conditions combined with effects related to climate change such as Arctic sea ice loss to spur and enhance epic drought conditions in California. Southeast Asia is already experiencing heat and dryness that is typically associated with a developing El Nino. Northern Brazil is also seeing increasing levels of heat and drought. To the North, Siberia is experiencing an extraordinary April onset to fire season while the northeastern US is somewhat cooler than average due to the persistent and anomalous strength of a dipole of warm temperature extremes in western North America and cool temperature extremes in eastern North America.

Many of these impacts, though expected in a normal El Nino year appear to be enhanced by effects related to human caused climate change such as sea ice loss and an amplification of the hydrological cycle increasing the frequency of extreme rainfall, drought and fire events (as in the California drought and the southeast Asian and Siberian fires).

(El Nino model runs by NOAA’s Climate Prediction Center show 66% potential for El Nino Development by November, December and January of 2014-2015. Image source:CPC/IRI.)

During a typical strong El Nino year, global weather disruptions can cause severe damage resulting in reductions to world GDP by as much as 5%. But with the added and enhanced severe weather effects due to climate change interacting with El Nino, overall impacts could be far more destructive. In addition, a release of what is currently record Pacific Ocean heat content into the atmosphere will likely set off new high temperature extremes, further pushing the global climate system toward the very dangerous 2 C warming threshold.

Links:

NOAA

CPC/IRI

Climate scientists find link between sea ice loss, emerging El Nino, and record California Drought

Small Army of Firefighters Battles Siberian Blazes in April

Monster El Nino Rising From the Depths

Winter of 2013-2014 Sees

Most Extreme Dipole on

Record

How a Strong Emerging El Nino Conspired With Climate Change to Ignite Record Drought in California and Collapse the Polar Vortex

Robertscribbler,

17 April, 2014

Dipole. It’s a word often used among meteorologists and climate scientists. But what does it mean?

In weather terms we can simply think of it as this: one side hot, one side cold. So, as a basic principle, it’s pretty direct. But in a world where extremes between hot and cold are becoming more intense, in North America which has just experienced its most extreme dipole anomaly since record keeping began in 1960, it’s also something that’s important to understand as it relates to ongoing human-caused climate change.

For a recent blockbuster scientific paper by Dr. Simon Wang and associates and published in Geophysical Research Letters has now linked this extreme temperature differential, related polar vortex collapse events, and the California drought with both ongoing physical changes to the Earth System due to human caused climate change and to the first rumblings of a monster El Nino in the Pacific.

Envisioning a Dipole Pushed into An Extreme Form by Climate Change

But to understand how an excessively extreme dipole relates to the historic events of the winter of 2013-2014, it helps to open up one’s imagination. It helps to describe the ground-breaking information provided by Dr. Wang’s new paper in descriptive terms. It helps to, at first, envision a wave. Then to imagine the up-slope of the wave forming a hot, red shape. Now imagine the down-slope forming a cold, blue shape. Now think of this wave growing more intense, extending further in both its up-slope and in its down-slope. Growing hotter on the up-slope side and comparatively colder on the down-slope side.

(GFS Model summary of Polar Vortex Collapse event on January 19, 2014 shows 850 mb temperatures over the Eastern US colder than the same temperatures over parts of Greenland and the Arctic Ocean. 850 mb temperatures over St. Augustine, FL are the same as 850 mb temperatures over central Greenland. Anomalies on the hot side of the dipole in the Arctic hit +40 degrees Fahrenheit in some places. Anomalies on the cold side of the dipole hit more than -35 degrees F in some places. Note the twin, dense high pressure systems sitting sentinel just off the California Coast and deflecting storms north into Alaska. Image source: NOAA/GFS.)

Having established the wave form and related temperature extremes, lay the shape over North America and adjacent Pacific Ocean. The up-slope covers the Eastern Pacific, Alaska, a section of the Beaufort Sea in the Arctic, Western Canada and the Western US. The down-slope swings from the eastern side of the Beaufort, on in through Central and Eastern Canada and bisects the US diagonally from the Dakotas to the Gulf Coast east of Texas.

Now let’s envision this wave as a flow of upper level air called the Jet Stream and let’s think about the various atmospheric aspects that feed it. Looking west, we happen upon a very warm pool of water in the Western Pacific east of the Philippines. This warm pool is the source of an El Nino that will likely occur within one years time. A heat pocket given added intensity by both rising atmospheric temperatures and strong winds transferring that added energy into the vast Pacific Ocean. The heat waits, wanting to spread out across the Pacific surface in an energetic return to the air. But, for now, it simmers in its deep pool, providing energy for the powerful dipole we’ve just described.

The heat from this warm pool radiates into the atmosphere creating lift. Further north, a cold pocket is driven south by another strong atmospheric wave pattern over the Asian continent. The cold air pocket runs south over Japan. The hot and the cold difference generates a very strong upper level synoptic (horizontal form weather patterns stretching more than 1,000 kilometers) wind pattern that stretches all the way across the Pacific Ocean.

The winds run southwest to northeast until they encounter the hot bulge of our already described dipole over the Eastern Pacific near the US west coast and Canada. This warm current turned the already rapid winds due north where they rushed up over Alaska and into a sea ice pack far weaker than in decades past. A sea ice sheet gradually thinning, breaking up, and venting heat from a warming Arctic Ocean below. And so these, already strong, winds were not turned back by the now much weaker cold until they had driven far, far into the Arctic Ocean (and it is here that we must give a hat tip to Dr. Jennifer Francis, who finds her predictions regarding sea ice loss and high amplitude Jet Stream waves again validated).

(Upper level wind pattern on January 23, 2014 shows a polar vortex that has essentially been ripped in half by the warm side of the west coast dipole and the high amplitude Jet Stream wave forming over top of it. Image source: University of Washington.)

Now imagine a strong dome of high pressure forming in the wake of this powerful and ongoing wind flow, sheltered and growing ever stronger on the hot side of the dipole. Imagine it blocking the path of storms, even as it concentrated heat and warmth. Imagine California receiving 1/4 or less of its typical winter rainfall as a result. A most recent and extreme insult to years of drought forcing authorities to ration water in many places.

Now return to that strong wind finally being turned south somewhere in the far, far north, in the Beaufort Sea just south of the North Pole. Then imagine these now cold-laden winds rushing south. Running over Hudson Bay and eastern Canada. Roaring over the Great Lakes and carrying with them a cyclone of cold Arctic air that should have remained in the far north. The polar vortex that should have stayed over places like Svalbard but instead collapsed under the warm wind flow and shifted far south to places like Toronto or Chicago or Detroit or Washington DC.

Now at last imagine another synoptic pattern as the Arctic air of the polar vortex encounters the warmth of the Gulf Stream. This pattern is laden with powerful storms that bomb out over the UK again and again, resulting in the stormiest winter for that island nation in over 200 years.

And here we have the dipole of the winter of 2013 and 2014. A west coast that was hot, hotter than usual all the way from California to the far north of Alaska and an East Coast that from Canada to the Gulf Coast became the repository for cold, cold Arctic air that was shoved south as the polar vortex collapsed down the steep face of the one of the largest and longest lasting Jet Stream waves on record.

(Dr. Francis explains how polar amplification results in higher amplitude Jet Stream wave patterns.)

Dipole. One side hot. One side cold. But, in this case, in the case of the winter of 2013-2014, it’s a historic and anomalous dipole. A freak born of the climate change we’ve caused mixing up with the Pacific Ocean heat of a rising El Nino. A record hot, dry winter for the US West that ignites wildfires in winter and forces the government to ration California water resources. A severe dry spell that closes farms and drives US food prices up by 15%. A record cold, stormy winter in the Eastern US and a series of super-intense storms screaming across the North Atlantic to submerge Somerset and rip massive chunks out of a rocky UK coastline.

This clear picture of a climate-change caused event was this week provided through the groundbreaking new research by Dr. Wang and fellows. These top scientists engaged climate models and analyzed past records to find the culprits of the weather extremes we witnessed during this past winter. And what they found was a very high correlation in the models with the extreme dipole over North America and the Arctic, an oncoming El Nino, and climate change driven impacts.

For not only was this year’s dipole the most extreme on record, it was also likely made far more extreme by an emerging Monster El Nino acting in concert with severe global-warming related reductions in Arctic sea ice cover, increases in Pacific Ocean heat and atmospheric moisture content, and related changes to the upper level air flows of the Northern Hemisphere polar Jet Stream.

Links:

Probable Causes of the Abnormal Ridge Accompanying the 2013-2014 California Drought, ENSO Precursor and Anthropogenic Warming Footprint

NOAA/GFS

University of Washington

Read Further Excellent Reporting on the Wang Report Here:

California Drought/Polar Vortex Jet Stream Pattern Linked to Global Warming

Bombshell Study Ties Epic California Drought ‘Frigid East’ To Manmade Climate Change

Large and Growing List of Scientific Studies Linking Human Climate Change to Current Weather Extremes (hat tip to Weather Underground)

Changing the Face of Mother Nature

The Seasonal Atmospheric Response to Projected Sea Ice Loss in the Late 21rst Century

Evidence Linking Arctic Amplification to Extreme Weather in the Mid Latitudes

Influence of Low Arctic Sea Ice Minima on Anomalously Cold Eurasian Winters