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Ocean Temperature Anomaly Hits Extraordinary +1.12 C Above Average Reading on April 22, All Australian Weather Models Now Predict El Nino for 2014
22
April, 2014
With
the ever-more certain approach of El Nino, the world ocean surface is
starting to radiate more and more heat.
Over
the past four days, GFS assessments have shown positive temperature
anomaly values in excess of +1 degrees Celsius (C) above the, already
hotter than normal, 1979 to 2000 average (which was, itself, about .5
C above the low averages seen during the period of 1880 to 1920).
With each new dawn, readings ramped higher and, by today, those
temperatures had spiked to an extraordinary +1.12 C hotter than
‘normal’ for the entire global ocean system.
(Global
oceans hit extreme +1.12 surface temperature anomaly. Data from
NOAA’s Global Forecast Systems model visually depicted by the
University of Maine’s Climate
Reanalyzer.)
The
equatorial Pacific region hovered near El Nino values with readings
of +.44 to +.45 C approaching the El Nino threshold of +.5 C. It is
worth noting that the Eastern Equatorial Pacific has consistently
shown below average temperatures during recent years as strong trade
winds drove both upwelling of cooler waters and atmosphere-to-ocean
heat transfer. Meanwhile, the Western Pacific spiked to much hotter
than normal readings as heat content just kept piling up in a broad
zone east of the Philippines.
Extraordinary
high temperature departures have also cropped up across other
regions. The Northern Hemisphere, for example, showed an
extraordinary +1.56 temperature anomaly for April 22. This
exceptional reading was fed by extreme northern ocean temperatures in
the Barents Sea above the Arctic Circle at +4-5 C above the 1979 to
2000 average and a very warm pool in the Pacific Ocean south of
Alaska ranging from 1.5 to 2.5 C hotter than normal.
Aside
from these zones of extreme heat, almost all Northern Hemisphere
waters now display hotter than average temperatures.
All
Australian Models Now Show El Nino
These
excessively high global ocean temperature readings come on the same
day that the Australian Bureau of Meteorology (BOM) issued new
findings showing that every climate model run by that agency now
predicts El Nino for 2014. The BOM notes:
The likelihood of El Niño remains high, with all climate models surveyed by the Bureau now indicating El Niño is likely to occur in 2014. Six of the seven models suggest El Niño thresholds may be exceeded as early as July.
At
issue is the fact that reversals of the trade wind, known as west
wind back-bursts (WWB), are currently ongoing both east of the
Solomon Islands and in the Central Pacific Ocean. Real-time
observation of western Pacific wind flow through composite weather
model data shows a broad field of westerly winds of about 5-15 mph
velocity centered at 1.7 degrees South, 156 degrees East. A second
cyclonic circulation north of Tahiti at 2.9 North, 139 West in the
mid Pacific Ocean has also generated a 5-15 mph west wind.
Overall,
these counter trade wind flows help to push down-welling warm water
in the Western Pacific eastward, spreading hot waters across the
surface and amplifying the force of what,
during March, was the most powerful Kelvin Wave on record.
Factors that bring with them the potential
for an extraordinarily powerful monster El Nino for 2014-2015,
continued positive ocean surface temperature extremes, and major
weather disruptions associated with both human warming and the global
tilt toward the warm extreme that is El Nino.
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Hat
Tip to Colorado Bob
Potential For El Nino Spikes As Record Pacific Ocean Heat Content Continues to Emerge
(Very
powerful Kelvin Wave still moving eastward even as it begins to sink
in off the coast of South America. Image source: NOAA.)
22
April, 2014
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.
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