Posted on 10/05/2022 12:08:51 PM PDT by Red Badger
As the world braces for a third consecutive year of exceptional La Niña conditions, a new study reveals how our climate models might have missed this disastrous 'triple-dip' effect.
It's the first time in a century that La Niña has stuck around for so long, and her wrath is being felt in southern Africa and South America in the form of drought, and in Australasia and South-East Asia in the form of floods.
Her conditions are also set to bring a cool, wet winter to the Pacific Northwest and a hot, dry one to the southwest of the United States.
La Niña is El Niño's somewhat overlooked twin sister, at least when it comes to our climate models. The Pacific Ocean naturally oscillates between El Niño and La Niña conditions, occuring once every couple of years.
Under what are regarded as normal conditions, strong trade winds push the surface layer of the Pacific Ocean west, dragging a layer of warm water like a finger dragging a page in a book. Deeper, cooler water rises to replace it near the Central American coast, establishing temperature and moisture conditions for local weather patterns.
El Niño occurs when the trade winds weaken, leaving the cool waters in the Pacific's east trapped beneath a warm surface. The result is less rain over places like Australia, and more precipitation in the US Southeast. La Niña occurs when the trade winds strengthen, exposing more of that cool water. As a result, the jet stream high above gets nudged north, pushing rains that would normally fall on the southern US much further north.
With global warming generally increasing sea surface temperatures, both El Niño and La Niña are expected to become more frequent and severe, with extreme events occuring once a decade instead of once every twenty years.
So why is La Niña running the show right now? While climate models accurately paint the big picture on future trends, predicting the precise swing of the pendulum is taking some work.
"The climate models are still getting reasonable answers for the average warming," says atmospheric scientist Robert Wills from the University of Washington, "but there's something about the regional variation, the spatial pattern of warming in the tropical oceans, that is off."
Looking back at El Niños and La Niñas since 1979, researchers found a discrepancy between real-world observations and 16 current climate models.
These models were unable to reproduce reality in both equatorial and midlatitude oceans. Only one even got remotely close.
As the climate crisis steps up, sea surface temperatures appear to be on a general incline. Still, in the east Pacific and southern oceans, there is more cooling happening than expected.
"While biased trends have been previously identified in the equatorial Pacific, our work shows that biased trends are a much more widespread problem in climate models," the authors write.
Even though climate models can reproduce observed sea surface temperature trends quite reliably in the short term, something is clearly missing from the long-term picture.
Some studies suggest a ten-year swing in Pacific conditions can explain the discrepancy. But even when that swing took place two years ago, there were still observed anomalies in the South Pacific.
Perhaps there is an overlooked natural variable in the southern ocean that spans multiple decades.
Or perhaps it's climate change.
UW researchers say their findings have led them "to conclude that it is extremely unlikely that this pattern of trend discrepancies results entirely from internal variability."
There are several reasons why cooling in the Southern Ocean could be due to escalating atmospheric temperatures forced by human emissions.
Sea ice melt is one option; another is a shift in surface winds due to greenhouse gases and changes to the ozone layer.
But these changes will likely only be temporary. In the long run, the east Pacific and Southern Oceans will eventually warm, researchers at UW argue. And when they do, they could be even more vulnerable to the effects of climate change than other regions.
"A future shift toward a warming pattern with more warming in the eastern equatorial Pacific would also lead to major changes in the Walker circulation and the associated large-scale circulation and precipitation patterns," the authors write.
Unless climate scientists can figure out why sea surface warming is so delayed in the east Pacific and Southern Ocean, the team says we will be left "with a huge source of uncertainty in multi-decadal projections of regional and global climate."
For now, scientists don't know when La Niña will lose the upper hand. Climate change could continue to favor her for years to come.
The study was published in Geophysical Research Letters.
Don't make me sic a moose on your sister.
But one of these times it will be the Big One, lasting 110,000 years or so. A full-blown ice age is due any century now.
Yeah, ‘details missing’; like the Arctic will be ice free, children in Britain won’t know what snow is, pacific islands will be underwater (or else tip over), just a few minor details like that.
Nonsense.
The answers are pre-determined by those building the models.
If the "answers" are not "reasonable", the people building the models tweak the models.
That is how it is done. There are many variables which have unknown values. Those values are tweaked to make the model look "reasonable".
No need to read further...
“La Niña’s Shock Return Suggests Important Details Are Missing in Climate Models”
not possible: climate “science” is “settled” ...
The La Niña,El Niño phenomenon was knwn by the indigenous of the west coast of the Americas hundreds of years ago and watched closely.
My mother born 1913 in Arizona, learned of it and did her own almost infallible predictions of the weather based on it.we children all respect those who live by their own watchful eyes according to it position in the Pacific.
The frigging SUN is missing from these ‘models’.
There’s a 40-thousand mile long ridge of volcanic activity running under the world’s oceans. Both volcanos and hot smokers are transferring terawatts of heat to the oceans daily. This heat flow is assumed to be constant, so it’s not categorized as a ‘variable’ in climate and weather. But we really don’t have a way of measuring the heat transfer or charting it over time.
The core and mantle are heated by fission. Radioactive decay constantly heats the core and that heat drives columns of magma up through the crust. The heat flow and distribution are manifestly lumpy because there is significant variability in volcanic activity over both near-term and geologic time.
Most likely Earth’s core heat migrates towards the surface slowly in giant viscous clumps or bubbles of hotter and less dense material. Sort of like how the material behaves in a lava lamp except on a much longer time scale.
With all this bubbling going on I see no reason to assume the geothermal heat flow into the ocean is completely constant, absent scientific proof. I do see reason to assume the heat flow varies according to the number and intensity of undersea eruptions from one year to the next. The heat flow IS a ‘variable’.
In more general terms, it should be pointed out that before the AGW period there was no working theory of what caused the Pacific to undergo its periodic shifts from El Nino to La Nina states (several variants are recognized, it’s a little more complex than just either/or), and there was never any attempt made by AGW theorists (whether they are right or wrong) to explain the variations or to postulate whether AGW would change the balance.
So in other words, the Pacific variations remain separate from AGW theory and you could postulate that if AGW has some partial merit (humans are partly or even mostly responsible for the recent warming observed) that merit does not extend to any new or greater understanding of these Pacific variations. Pretty much the same can be said for other signals like the Atlantic Oscillation. The best AGW could claim is that they have introduced a theory that takes the old pre-AGW climate and warmed it up by about 1 C degree, without explaining any of the variations within the regional trends (other than some claims made that variability is increasing, itself a controversial claim).
Personally, I might expect in a generally warming climate that El Nino would lose frequency and La Nina would gain frequency; the reason for that is that stronger subtropical highs tend to promote La Nina (by driving more cold water north along the west coast of South America, it is when that process weakens that El Nino patterns develop, so they are correlated with weaker subtropical highs). Some of the observed northern hemisphere weather correlations with El Nino or La Nina may not be direct consequences but just similar responses if the two hemispheres see similar trends in the strength of subtropical highs. This could in theory not be linked either by hemispheres or by different ocean systems. So it’s all rather complex and as we have seen, the AGW approach is a simple one and does not handle complexity very well.
But the science is settled.
Another good one!
In a few years Climate Alarmists will need a BIG EXCUSE to explain why "nothing is happening". La Niña is El Niño can be their out - why the 'mother ship' never came to get them.
So why don’t we humans stop it? We are all powerful,like the dinosaurs
With global warming generally increasing sea surface temperatures.
Sun cycles not reported doesn’t fit agenda.
Thank God my sister is dead.
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