Tropical air circulation drives fall warming on Antarctic Peninsula
The eastern side of the Antarctic Peninsula, a finger of the southern polar continent that juts toward South America, has experienced summer warming of perhaps a half-degree per decade – a greater rate than possibly anywhere else on Earth – in the last 50 years, and that warming is largely attributed to human causes.
But new University of Washington research shows that the Southern Hemisphere’s fall months – March, April and May – are the only time when there has been extensive warming over the entire peninsula, and that is largely governed by atmospheric circulation patterns originating in the tropics.
The autumn warming also brings a notable reduction in sea ice cover in the Bellingshausen Sea off the peninsula’s west coast, and more open water leads to warmer temperatures on nearby land in winter and spring (June through November), said Qinghua Ding, a UW research associate in Earth and space sciences. In fact, the most significant warming on the west side of the peninsula in recent decades has occurred during the winter.
“Local northerly wind pushes warmer air from midlatitudes of the Southern Ocean to the peninsula, and the northern wind favors warming of the land and sea ice reduction,” said Ding.
He is the lead author of a paper explaining the findings, published online this month in the Journal of Climate. Eric Steig, a UW professor of Earth and space sciences, is co-author. The work was funded by the National Science Foundation.
The scientists analyzed temperature data gathered from 1979 through 2009 at eight stations on the Antarctic Peninsula. The stations were selected because each has reliable monthly data for at least 95 percent of the study period. They also used two different sets of data, one from Europe and the other from NASA, that combine surface observations, satellite temperature data and modeling.
A German research vessel, Polarstern, is shown off the Rothera station on the west coast of the Antarctic Peninsula. Rothera is one of eight stations that provided temperature data for this research.
The researchers concluded that the nonsummer Antarctic Peninsula warming is being driven by large-scale atmospheric circulation originating in the equatorial Pacific Ocean. There, the warm sea surface generates an atmospheric phenomenon called a Rossby wave train, which reaches the Antarctic Peninsula and alters the local circulation to warm the region.
The sea-surface temperature trend in the tropical Pacific is related to natural phenomena such as the El Niño Southern Oscillation (El Niño and La Niña) and cycles that occur on longer timescales, sometimes decades. But it is not clear whether human causes play a role in that trend.
“We still lack a very clear understanding of the tropical natural variability, of what that dynamic is,” Ding said.
He said that in the next two or three decades it is quite possible that natural variability and forcing from human factors will play equivalent roles in temperature changes on the Antarctic Peninsula, but after that the forcing from human causes will likely play a larger role.
“If these trends continue, we will continue to see warming in the peninsular region, there is no doubt,” Ding said.
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“If these trends continue, we will continue to see warming in the peninsular region, there is no doubt,” Ding said.
In other words, if things continue what they have been doing, we will continue seeing what they’ve been doing.
A tautology that takes genius, hard work and a lot of grants to get peer-reviewed and published.
The warming on the eastern tip of the peninsula has been attributed to an increase in northerly winds that are not just warmer but that have altered there flow patters. Instead of of going around the peninsula the winds go up and over causing foehn storms. The melt ponds that were created on the Larsen Ice Shelf just before the collapse can be attributed to these foehn storms. Even during a cold Antarctic night in the McMurdo Dry Valleys foehn storms have raised temperatures by 90 degrees F. Steig blogged at RealClimate and mentioned the “hockestick” meltings f the glaciers on James Ross Island at the tip of the peninsula and suggested CO2 warming but it too is at the focus of the adiabatic (without adding heat) warming by foehn storms. Of course once I posted reference to foehn storms my post was deleted by RealClimate.
See Orr, A., et al., (2008), Characteristics of summer airflow over the Antarctic Peninsula in response to recent strengthening of westerly circumpolar winds, J. Atmos. Sci., 65, 1396–1413.
Massom, R., et al., (2006), Extreme anomalous atmospheric circulation in the West Antarctic Peninsula region in austral spring and summer 2001/2, and its profound impact on sea ice and biota, Journal of Climate, vol. 19, p. 3544– 3571.
Steionhoff, D., et al. (2012) Dynamics of the Foehn Mechanism in the McMurdo Dry Valleys of Antarctica from Polar WRF. Quarterly Journal of the Royal Meteorological Society.
Good point Doug…if we continue to see why we don’t understand, we will still not understand it. Maybe we should introduce ANOTHER variable. There was a running debate at Spencer’s blog this week where the subject of Lake Vanda was used to support a gravity induced heat source. This second highest saline content lake on the planet has a reverse thermal profile, from the only depth/temp data set ever measured. The surface is ice covered, but beneath that, the water temp of 4C rises to 23C at the lake bottom. The original 1976 data has been interpreted to mean that UV light penetrating beneath the ice cover is the only possible source of heat, based on six weeks of Antarctic summer only data collection. This lake also has a steep saline gradient with depth and is located totally within the Antarctic Rift zone, which extends to the peninsula. This ridge includes some of the highest mountains on Earth, which would normally have lower thermal image temps. The northern “red” and continuous “yellow” of this ridge, with “blue” on both sides near the pole can ONLY indicate geothermal upwelling along this ridge line, which does include the active Antarctic volcanos. Lake Vanda’s saline “antifreeze” is only “capturing” some of this geo-thermal flux.
Maybe geothermal energy is a variable in surface temperature and Earth climate changes.
AGW was supposed to exhibit polar amplification based upon the simple physics of radiative heating. Dr. Steig responded to a question I asked at Realclimate that there was basically no way to discern polar amplification of CO2-driven warming from all the climate complexity in the Antarctic. In other words, even the mention of anthropogenic attribution of Antarctic warming is pure hyperbole.
The West Antarctic Peninsula would normally grow when the sun is weak with more frequent air flows into and out of the continental interior (a cooling period) but shrink when the jets are more poleward and more tightly directed around the continent (a warming period). The position of the West Antarctic Peninsula is a by product of the land distribution around it. The air flow around Antarctica is disturbed by the land mass of South America so when during a cooling period with equatorward jets there are more frequent flows of air into and out of the interior the favoured route for cold outflows is across the West Antarctic Peninsula which then grows.
So, during a tropospheric warming period the main part of Antarctica cools because there is less in the way of northerlies entering the interior but the West Antarctic Peninsula is skimmed away by the tighter run of winds around the Antarctic from the more poleward jets.
During a tropospheric cooling period the interior of Antarctic will be a little less cold due to more air flowing in and out from more equatorward jets but the West Antarctic Peninsula will grow back again because that is the favoured route for outflow of cold air.
“…issues of global warming in Antarctica have pretty much cooled”.
But look at the map – it’s red hot. How can we deny such a fierce colour? Surely we are doomed!
I’m frightened.
“If these trends continue, we will continue to see warming in the peninsular region, there is no doubt,” Ding said.
So, according to this highly qualified scientist, if the warming trend continues we’ll continue to see warming.
Gee, who’da thunk it, huh?
“a greater rate than possibly anywhere else on Earth – in the last 50 years, and that warming is largely attributed to human causes.”
I hate it when religious statements make there way into scientific papers. Of course, if this mantra was not repeated, it would not get funding or be published or future funding would be limited.
So, here we have a paper that largely contradicts a prior paper that could be skeptic fodder and STILL this type of statement must be included.
In a recent survey of papers, this one, too, would count as an AGW consensus paper.
Why these ‘scientists’ don’t think that logical thinking people of the mass public don’t gag at these types of unbacked up statements of religion, is beyond me.
“Maybe geothermal energy is a variable in surface temperature and Earth climate changes.”
Well, it must be to a certain extent. Just think about the traveling hot spot under the Hawaiian islands and black smokers/geothermal vents/undersea volcanoes. Has that heat budget been quantified, and how variable is it? Sometimes I wonder whether ENSO can have geothermal drivers behind the heat pulses. Wild flights of fancy moments I wonder whether the sun’s magnetic field can effect the metal core of our planet and influence rotation or stability in strange ways.
In the dry valleys the winds are katabatic, Jim, not foehn, as they are coming off the internal plateau. The winds driven up over one side of the peninsula and back down would indeed be foehn or rain shadow winds.
Many readers would enjoy Adam Smith’s comments 240 years ago concerning public colleges and the teachers therein. Wealth of Nations, book 5, which you can download from Project Gutenburg. Located about 32% of the way in. It’s too long to quote here, but some pointed comments concerning the natural tendency to corrupt public teachers in a system which includes features like tenure, take-it-or-leave it prices, and required diplomas from the system. Basically, except where there is a market for a better diploma and/or better teaching and/or better prices (and add better research), the incentives work all wrong, and the problem are centuries old.
As people have said many times, Thank Goodness for the guys who stand up to a system like that, and particularly the writers here.
I find this statement to be eminently contestable: “The eastern side of the Antarctic Peninsula … has experienced summer warming of perhaps a half-degree per decade – a greater rate than possibly anywhere else on Earth – in the last 50 years”. Yeah, right, what are the odds that if you inspect that temperature record you’ll find massive downwards adjustments in past data, or even entirely made-up data. No inconvenient natives to muck up the “historical temperatures” with on-the-ground observations! AGW works best in unpopulated areas where the climateers can draw the temperature charts any way they want.
‘The stations were selected because each has reliable monthly data for at least 95 percent of the study period’ because these are the least worst part of the continent when it comes to living with the weather therefore have had stations there for the longest time .
I wonder how many geothermal studies of the water off the coast were conducted? Would that be zero? You’ve heard of new math … well, this is new science. Science by ignorance and assumption.
“We still lack a very clear understanding of the tropical natural variability, of what that dynamic is,” Ding said.
He said that in the next two or three decades it is quite possible that natural variability and forcing from human factors will play equivalent roles in temperature changes on the Antarctic Peninsula, but after that the forcing from human causes will likely play a larger role.
Right. They don’t understand natural variability but feel confident enough to state that forcing from human causes will overtake that from natural variability in the future. I wonder if they controlled for the urban buildup of the stations where those readings were taken? I’d bet that in those 30 years the infrastructure of those stations grew considerably.
For an anomaly range of -0.5 to +0.5 it is difficult to refrain from LOL at the color range chosen to represent it.
I find it really interesting that “new” papers are basically rehashing observations and conclusions drawn a while ago by the late prof. Marcel Leroux in his last version of “Dynamic Analysis of Weather and Climate” 2nd English ed. 2010 and likely without referencing his work.
I better understand now why grave digger William Connolley did everything he could to erase the Leroux wikipedia English page. Between warmists and envious skeptics, pillaging seems the rule over decency.
Ch. 14.2 page 350: “So, the warming of the Antarctic Peninsula is of dynamical origin, and the ‘greenhouse effect’ extolled by the IPCC has, in consequence absolutely nothing to do with it.
This warming is controlled by an intensification of meridional exchanges by MPHs rolling off the Antarctic and causing additional warm, moist air to be transferred towards the South Pole.”
Is there an actual subject called Mannian math, in the same way as we have Bayesian statistics or Brownian motion?
If not, it sounds like an excellent subject for study, to serve as a horrible example for future generations.
“He said that in the next two or three decades it is quite possible that natural variability and forcing from human factors will play equivalent roles in temperature changes on the Antarctic Peninsula, but after that the forcing from human causes will likely play a larger role.”
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I burned out of my last job after 2.3 decades, now I just observe.
So, we’re getting worried about a ~0.8c variance over the entire continent of Antarctica? Am I reading that right?
Mods: Sorry about misspelling my name in the other thread.
@Max™ says: In the dry valleys the winds are katabatic, Jim, not foehn, as they are coming off the internal plateau. The winds driven up over one side of the peninsula and back down would indeed be foehn or rain shadow winds.
I understand your point but you are assuming all dry valley winds are katabatic. There has been much discussion about correctly distinguishing the 2 in the dry valleys.
Read Steionhoff, D., et al. (2012) Dynamics of the Foehn Mechanism in the McMurdo Dry Valleys of Antarctica from Polar WRF. Quarterly Journal of the Royal Meteorological Society.
Participants here and nowhere else are responsible for global warming,climate change or any other name you wish to call the belief that humans can control planetary temperatures within a certain range.Playing along with those who have salaries,reputations and lifestyles based on the charade is the only thing I see and how that helps humanity understand how climate is actually defined rather than the rigged ‘definition’ which suits modelers and those who know no better.
For quite some time I have been familiar with the vicious strain of empiricism that turned natural sciences from a largely interpretative endeavor into a speculative/predictive romp where all the damage is done and one thing is certain,the type of mind which is given towards projecting a conclusion,regardless of how dumb it is,does not stop regardless of what arguments are brought before them –
” I have heard such things put forth as I should blush to repeat–not so much to avoid discrediting their authors (whose names could always be withheld) as to refrain from detracting so greatly from the honor of the human race. In the long run my observations have convinced me that some men, reasoning preposterously, first establish some conclusion In their minds which, either because of its being their own or because of their having received it from some person who has their
entire confidence, impresses them so deeply that one finds it impossible ever to get it out of their heads. Such arguments in support of their fixed idea as they hit upon themselves or hear set
forth by others, no matter how simple and stupid these may be, gain their instant acceptance and applause. On the other hand whatever is brought forward against it, however ingenious and conclusive, they receive with disdain or with hot rage–if indeed it does not make them ill ” Galileo
By definition,a planet’s climate cannot change as primarily there is such a thing as a climate spectrum.A planet with a 90 degree inclination like Uranus has a polar climate while Jupiter with its 3 degree inclination has an equatorial climate ,the Earth with its 23 1/2 degree inclination has a largely equatorial climate with a smaller polar component hence the degree of inclination acts like a dial in determining where in the spectrum between equatorial and polar a planet’s climate is.
http://imgsrc.hubblesite.org/hu/db/images/hs-2007-32-g-web.jpg
http://oceanworld.tamu.edu/resources/ocng_textbook/chapter04/Images/Fig4-1s.jpg
The empirical community may have been successful in rigging climate as ‘statistical long term weather’ or something like that in order to pass off climate modeling in the same way as weather forecasting but it is for this reason that the whole charade exists.Had the opposition raised the conceptual and intellectual standards by which climate is defined astronomically,none of this mess would ever have happened or at least gained momentum in the wider world.
“Maybe geothermal energy is a variable in surface temperature and Earth climate changes.”
Well, we (some scientists) now estimate the center of the Earth to be much hotter (20% or 1000 degrees) then thought before, http://www.messagetoeagle.com/earthcenterhot.php
Now calulate the average flow of heat through the crust at average ocean depth, and this, with more volcanoes per sq K then on land due to thinner crust, and add in the residence time of said thermal heat, (meaning if said heat takes x years to reach the surface, then said heat is cumlitive for all of that time) and you may get a decent wag as to the thermal heat content of the worlds oceans. (Has anyone seen anything like this done?)
Well, yeah, I assume there would still be foehn mechanisms in play, but most of the evaporation would be due to katabatic winds simply because of the location of the valleys relative to the plateau, just stood out because I was working on a powerpoint project for a class and chose the McMurdo ecosystem out of curiousity.
Apparently the top predator is a nematode!
Definitely need to learn about these Rossby wave trains originating in the tropics!
David wrote –
“Now calculate the average flow of heat through the crust at average ocean depth, and this, with more volcanoes per sq K then on land due to thinner crust, and add in the residence time of said thermal heat, (meaning if said heat takes x years to reach the surface”
In 2005 I presented a mechanism which combined the 26 miles spherical deviation of the planet with crustal motion/evolution based on an uneven rotational gradient between equatorial and polar latitudes known commonly as differential rotation.By 2007 the wider community got wind of this rotational mechanism but instead of outlining the proper reasons using fluid dynamics of the interior they created a Frankenstein’s monster of a thing based on chanting voodoo.The point is that the stationary Earth,thermal driven ‘convection cells’ concept is dead as a concept whether you know it or not.
It is the way they grafted in the Earth’s rotation as a mechanism as an ongoing process to replace ‘convection cells’ in the space of a few years that I find astonishing just as ‘global warming’ altered to ‘climate change’ in the same sleight of hand way but that is how academics behave nowadays.
I don’t mind,sooner or later to explain plate tectonics using an uneven rotational gradient of the fluid interior they will run into the 26 mile spherical deviation between equatorial and polar latitudes hence it is not possible to stumble your way to a rotational mechanism,the answer is already embedded in the Earth’s shape and surface features.
This is the money paragraph:
“He said that in the next two or three decades it is quite possible that natural variability and forcing from human factors will play equivalent roles in temperature changes on the Antarctic Peninsula, but after that the forcing from human causes will likely play a larger role”.
There are no stations in the East Antarctic Peninsula — see http://upload.wikimedia.org/wikipedia/commons/f/f6/Antpen-en.png . Why is that? Because it’s too cold for our intrepid scientists. So now they say that it’s the fastest-warming place on Earth, yeah, right, no penguin will disagree. It’s yet another disgraceful episode of Climate Science.
It’s because we live on a slowly tilting planet. (Apologies to Madeleine L’Engle.) Earth’s axis is tilting towards vertical (or its theorized minimum angle) and as it inexorably trends that way, the overall climate will grow more temperate. There’s less polar surface area that is continuously in light or darkness some part of the year than there was any time in recorded history, and that area will continue to shrink for several thousand years to come. I wouldn’t be surprised if much of the polar ice does melt when the axis reaches whatever its minimum angle will be.
Where does much of the storm activity in the polar regions happen? Around the Arctic and Antarctic circles. What’s been happening to those circles for thousands of years? They’ve been moving polewards. The storm belts move with their respective arctic circles. The circles have moved polewards quite a ways during recorded history. Has anyone yet bothered to examine the effect of that factual happening on the climate?
Ignoring the influence of changes in Earth’s axial tilt on the climate is just as stupid as ignoring the fluctuations in total Solar radiation influx. “But it’s only a small amount.” Aye, but it’s a small amount over a very large surface. It adds up to a rather huge number.
One can apply all the math they want to calculating Earth’s min/max axial tilt. It’s still only a theory until it reaches one extreme or the other and some person with the ability to measure the angle is there to do it, which has never yet happened in recorded history. Nobody knows but Earth might skip right on past “minimum” axial tilt and go straight on to straight up, human calculations be damned. None of us now living will be here to see it. Calculations = theory. Direct observation and measurement = fact. When the measurements don’t agree with the theory, the theory is wrong, but when the chance to take the measurements only come around every 40,000 years (so theory says) theory is all we have.
Wobble, wobble http://www.michaelmandeville.com/earthmonitor/polarmotion/2006_wobble_anomaly.htm