Claim: UCLA study yields more accurate data on thousands of years of climate change

From the University of California – Los Angeles

Research also helps unravel the mystery of retreating glaciers in the Pacific Ocean’s western tropics

Using a cutting-edge research technique, UCLA researchers have reconstructed the temperature history of a region that plays a major role in determining climate around the world.

The findings, published online Feb. 27 in the journal Nature Geoscience, will help inform scientists about the processes influencing global warming in the western tropical Pacific Ocean. 

The study analyzes how much temperatures have increased in the region near Indonesia, and how ocean temperatures affect nearby tropical glaciers in Papua New Guinea and Borneo. Researchers also evaluated the accuracy of existing climate model predictions for that region. The findings illustrate that the region is very sensitive to climate change and that it has warmed considerably over the last 20,000 years, since the last ice age.

The team chose the specific area examined in the study because it is Earth’s warmest open ocean region and a primary source of heat and water vapor to the atmosphere. As a result, temperature changes there can influence climate not just regionally, but globally.

“The tropical Pacific ocean-atmosphere system has been called a sleeping dragon because of how it can influence climate elsewhere,” said lead author Aradhna Tripati, a UCLA assistant professor in the departments of Earth, planetary and space sciences, and atmospheric and oceanic sciences.

Tripati and her team used a technique known as clumped isotope thermometry, which examines the calcium carbonate shells of marine plankton for subtle differences in the amounts of carbon-13 and oxygen-18 they contain. The researchers analyzed extensive modern and geological datasets, conducted theoretical calculations and examined climate model output. The group discovered that temperatures have changed by about 8 to 10 degrees Fahrenheit (4 to 5 degrees Celsius) over that span — more than scientists had previously thought, and more than most models have estimated.

“Most global climate models underestimate the average temperature variations that the region has experienced,” Tripati said, adding that the other models’ simulations may be incomplete or the models are not sensitive enough.

The UCLA team’s conclusions about temperature changes in the region also imply that there have been major fluctuations in the volume of water vapor in the atmosphere there.

As part of the study, Tripati and her colleagues also investigated what sets the past and present height of glaciers in the tropics, and why they have been retreating. To accurately estimate the height of tropical glaciers and average temperatures at altitude in this region, they found that atmospheric mixing, through a process known as entrainment, needs to be factored in.

“We found that the large amount of ocean warming goes a long way to explaining why glaciers have retreated so much,” said Tripati, a faculty member in the College of Letters and Science and a member of UCLA’s Institute of the Environment and Sustainability. “Throughout the region, they have retreated by close to a kilometer since the last ice age, and are predicted to disappear in the next one to three decades. Previously understanding this large-scale glacial retreat has been a puzzle. Our results help resolve this problem.”

Among the implications of the study are that ocean temperatures in this area may be more sensitive to changes in greenhouse gas levels than previously thought and that scientists should be factoring entrainment into their models for predicting future climate change.

The group has already begun a follow-up study, looking at sediment from Indonesia’s Lake Towuti to develop data that can be used to further improve models of climate and water cycling for the region. Researchers will also look at other places in the tropics, the Western U.S. and China.

###

Co-authors of the study are Sandeep Sahany, postdoctoral researcher in the department of atmospheric and oceanic sciences, Dustin Pittman, graduate student in the department of atmospheric and oceanic sciences, Robert Eagle, assistant researcher in the department of Earth, planetary and space sciences, Jonathan Mitchell, assistant professor in the departments of Earth, planetary and space sciences and of atmospheric and oceanic sciences, J. David Neelin, professor in the department of atmospheric and oceanic sciences and Luc Beaufort, a research scientist at the Center for Research and Teaching of Environmental Geosciences in Aix-en-Provence, France.

The research was supported primarily by the National Science Foundation.

=================================================================

Paper: http://www.nature.com/ngeo/journal/v7/n3/full/ngeo2082.html

Modern and glacial tropical snowlines controlled by sea surface temperature and atmospheric mixing

Abstract

During the Last Glacial Maximum, tropical sea surface temperatures were 1 to 3 °C cooler than present1, 2, 3, 4, but the altitude of the snowlines of tropical glaciers5, 6 was lower than would be expected in light of these sea surface temperatures. Indeed, both glacial and twentieth-century snowlines seem to require lapse rates that are steeper than a moist adiabat7, 8. Here we use estimates of Last Glacial Maximum sea surface temperature in the Indo-Pacific warm pool based on the clumped isotope palaeotemperature proxy in planktonic foraminifera and coccoliths, along with radiative–convective calculations of vertical atmospheric thermal structure, to assess the controls on tropical glacier snowlines. Using extensive new data sets for the region, we demonstrate that mean environmental lapse rates are steeper than moist adiabatic during the recent and glacial. We reconstruct glacial sea surface temperatures 4 to 5 °C cooler than modern. We include modern and glacial sea surface temperatures in calculations of atmospheric convection that account for mixing between rising air and ambient air, and derive tropical glacier snowlines with altitudes consistent with twentieth-century and Last Glacial Maximum reconstructions. Sea surface temperature changes 3 °C are excluded unless glacial relative humidity values were outside the range associated with deep convection in the modern. We conclude that the entrainment of ambient air into rising air masses significantly alters the vertical temperature structure of the troposphere in modern and ancient regions of deep convection. Furthermore, if all glacial tropical temperatures were cooler than previously estimated, it would imply a higher equilibrium climate sensitivity than included in present models.

Looks like a pretty small and localized sample size:

Figure 1: Sites studied.

Sites studied.

Shown are core locations (806B, MD97-2138, V24-109) and mountains that were glaciated at the LGM

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Mike Smith

“The findings illustrate that the region is very sensitive to climate change and that it has warmed considerably over the last 20,000 years, since the last ice age.”
Gosh. I’m so happy to know that things have warmed since the last ice age. Will send more grant money ASAP.

Latitude

“Most global climate models underestimate the average temperature variations that the region has experienced,” Tripati said, adding that the other models’ simulations may be incomplete or the models are not sensitive enough.
oxymoron…………

I’m glad to report that my region has warmed considerably over the last 2 weeks. It’s nice.

Otter (ClimateOtter on Twitter)

glaciers in the Pacific Ocean’s western tropics – Yeah, I have to guess glaciers would NOT like the tropics.

Curious George

As usual, climate scientists paid from my tax money publish behind a paywall.

examined climate model output.

That is a bit disturbing given the lack of accuracy of “climate models”.

Yeah, Like this is, you know, fantastic science, why didn’t anyone ever think? Oh California.

John Tyler

“………We found that the large amount of ocean warming goes a long way to explaining why glaciers have retreated so much,” said Tripati……..”
Well then, what caused the ocean warming??
It is simply amazing that the explanations advanced to “explain” the retreating glaciers really do not explain anything at all , but just use some other “observed” event as the reason that something else happened.
Just DESCRIBING what has been observed does not constitute an EXPLANATION for a subsequent event.

Jimbo

“The findings illustrate that the region is very sensitive to climate change and that it has warmed considerably over the last 20,000 years, since the last ice age.”

I have woken up considerably since 3am. LOL.
The Pacific region is so sensitive to climate changes that it has been very detrimental to humans. We must act then!

“…..Half a world away in the tropical Pacific Ocean a similar saga unfolded. During the Greco-Roman climatic optimum, the Polynesians migrated across the Pacific from island to island, with the last outpost of Easter Island being settled around A.D. 400 (35)….”
http://www.pnas.org/content/97/23/12433.full

Jimbo

The study analyzes how much temperatures have increased in the region near Indonesia, and how ocean temperatures affect nearby tropical glaciers in Papua New Guinea and Borneo. Researchers also evaluated the accuracy of existing climate model predictions for that region. The findings illustrate that the region is very sensitive to climate change and that it has warmed considerably over the last 20,000 years, since the last ice age.

What about the other tropical glaciers? Are they sensitive to the considerable global warming since the last DE-GLACIATION as opposed to “the last ice age.” Are these people climate scientists? Time for bed.

Jimbo

For those who did not get my last comment we are still in an ice age I vaguely recall. My advanced apologies if I am wrong.

DD More

What sea level. Was not the sea level much lower or nonexistent at this time?

Konrad

“The tropical Pacific ocean-atmosphere system has been called a sleeping dragon because…”
Repent CO2 sinners or face the desolation of Smaug! Doom! Doooooom!

Rascal

Most logical people, skeptics and warmists, tend to agree that the Sun is the main source of energy for the Earth and the rest of the Solar System.
Similarly both skeptics and warmists seem to have questions about the causes of cycles or events that do not “fit” into any specific hypothesis.
Such situations require that we remember that the Sun and Solar System are part of a galaxy, which in turn is part of the Universe.
While the changes to the Sun’s activity may be the principal driver of weather and climate, who’s to say that extra-Solar events may account for inexplicable (at least presently) activity?

bushbunny

Yes Jimbo, we are experiencing an interglacial or interstadial. Volcanoes can heat up the sea, there are more undersea vents and volcanoes than terrestrial ones. One of my studies in post graduate forensic archaeology, was the ice man, or Ortzi. A volcanic eruption covered the mountain ranges where he was found with dust or ash. Because it could no longer reflect warmth from the sun, the region experienced a unseasonal melt. Didn’t last long though. They discovered other bodies too, even German troops from the second world war that had been covered by an avalanche and frozen in a glacier.

davidmhoffer

The models that are too sensitive to model the current climate are not sensitive enough to model the past?
Can’t even mock that.

TomRude

The key conclusion and probably why this stuff got in Nature to start with: “Furthermore, if all glacial tropical temperatures were cooler than previously estimated, it would imply a higher equilibrium climate sensitivity than included in present models.”
Higher sensitivity… from a line of dedcution that is of course much, much more precise than let say, works from hyper instrumentalized observations from the present day.

Eve Stevens

In central and southern Ontario this winter, highs have been below 30 year historic lows. I am happy I am not there. I imagine that the north eastern US is much the same. Did they think they could fool people into thinking it was warmer than it was?

Pamela Gray

I say, do what these authors say you should do, change the models to make them MUCH more sensitive. Whichever group of scientists cooked this one up, let em loose on the modelers. Ratchet those things UP!!!!!! What’s not to like about that? Stew: Meet your own pot.

Daniel G.

I don’t think they meant like climate sensitivity. Perhaps it is something else.

u.k.(us)

“The tropical Pacific ocean-atmosphere system has been called a sleeping dragon because of how it can influence climate elsewhere,” said lead author Aradhna Tripati,
==============
I always knew it was the “dragons”.
They’ve never been quantified.

Gary Hladik

“The tropical Pacific ocean-atmosphere system has been called a sleeping dragon…”
which has so far been quite beneficial to our climate system, agriculture, and civilization in general. Niiiiiice dragon. Maybe, like the Vikings in the Dreamworks film “How to Train Your Dragon”, some of us have badly misjudged this particular “dragon”. 🙂
http://en.wikipedia.org/wiki/How_to_Train_Your_Dragon_(film)

RMF

Abstract:
….
“We conclude that the entrainment of ambient air into rising air masses significantly alters the vertical temperature structure of the troposphere in modern and ancient regions of deep convection. ”
Translation: the warm air goes up into the air and is warm in a warmly fashion.
We’ve made some remarkable tentative conclusions around here as well. We’ve discovered that as the temperature is freezing the air around us (to wit, near us) is likewise in a cold manner but as the temperature structure warms, so doth the airith around uth. As we travel into space, the entrainment drops to nothing, and it is freezing as hell, until you fly into the sun, which burns like the stupid.

SIGINT EX

Looks like shit; i.e. far beneath the dignity of Bull Shit.

“Among the implications of the study are that ocean temperatures in this area may be more sensitive to changes in greenhouse gas levels than previously thought and that scientists should be factoring entrainment into their models for predicting future climate change.”
Why am I not surprised by that assertion?

John Tyler says:
March 14, 2014 at 6:13 pm
Just DESCRIBING what has been observed does not constitute an EXPLANATION for a subsequent event.
————————————————————————————————
Right, where is the supposed connection to agw via co2? It is never stated.

“UCLA researchers have reconstructed the temperature history of a region that plays a major role in determining climate around the world.”
Amazing !!! Wow knew, the that earths climate is controlled by the temperatures in western tropical Pacific Ocean. So I guess all we have to do is control the temperatures in western tropical Pacific Ocean and then we can control world wide temps.
Glad to know the “Experts” still want to ignore the Sun’s influence

RMF

““Throughout the region, they have retreated by close to a kilometer since the last ice age, and are predicted to disappear in the next one to three decades. Previously understanding this large-scale glacial retreat has been a puzzle.”
Is she also puzzled when, upon removing a tray of ice from her freezer and leaving it at room temperature prior to her trip to Indonesia, and then returning from said trip one month later to examine said ice tray, she finds the ice in the tray has retreated?

u.k.(us)

SIGINT EX says:
March 14, 2014 at 7:41 pm
============
Is that all you got, you do realize you didn’t say s#it, right ?
( you might have said it twice, but you are a long way from the record).

jbird

Yawn!

Robert of Ott awa

latitude, that is not an oxymororb, that is ox-shiy

Martin 457

I didn’t notice where volcanism was an attribute to this study. Did they miss it completely?
I just knew that somebody would try to take the temp of under-sea volcanoes and blame mankind for the anomalies. Not that sharp. (cutting-edge)

” we demonstrate that mean environmental lapse rates are steeper than moist adiabatic during the recent and glacial.”
Duh.

ROM

20,000 years ago
# NOAA Paleoclimatology
“20,000 years ago, global mean temperature 4 degrees C cooler than today, although the North Atlantic was 14 degrees C cooler. Lower sea level allows large-scale migrations of people into the Americas”.
# Australian Institute of Marine Science.
“20,000 years ago, the world was starting to emerge from the most recent ice age. The sea level around the Australian coast was then about 120 meters lower than it is today.”
# From Wiki re the Island of New Guinea which limits the southern boundary of the Pacific Warm Pool, the largest body of warm ocean waters on earth.
Puncak Jaya, the highest peak in SE Asia located in Indonesia’s West Papua province
“While Puncak Jaya’s peak is free of ice, there are several glaciers on its slopes, including the Carstensz Glacier, West Northwall Firn, East Northwall Firn and the recently vanished Meren Glacier in the Meren Valley (meren is Dutch for “lakes”).[11] Being equatorial, there is little variation in the mean temperature during the year (around 0.5°C) and the glaciers fluctuate on a seasonal basis only slightly. However, analysis of the extent of these rare equatorial glaciers from historical records show significant retreat since the 1850s, around the time of the Little Ice Age Maximum which primarily affected the Northern Hemisphere, indicating a regional warming of around 0.6°C per century between 1850 and 1972.
The glacier on Puncak Trikora in the Maoke Mountains disappeared completely some time between 1939 and 1962.[12] Since the 1970s, evidence from satellite imagery indicates the Puncak Jaya glaciers have been retreating rapidly. The Meren Glacier melted away sometime between 1994 and 2000.[13] An expedition led by paleoclimatologist Lonnie Thompson in 2010 found that the glaciers are disappearing at a rate of seven metres thickness per year and should be vanished by 2015.”
____________
Seems like that quite a number of researchers have been there before this lot of tax payer funding miners hove to on the scene.
Yep! the climate has changed.
The climate will continue to change
The climate is always changing
The constant climate change is the very item that has forced adaption and new strategies to emerge in every aspect amongst every life form on this planet .
And that has constant need to adapt to the ever changing global and local climate has driven the rise of intelligence and has created the immense diversity of life on this planet as life of every stature and type strives to adapt and prosper in that always changing climate.
A steady state global climate would lead to stagnation and the eventual very slow extinction of nearly every higher life form as well as intelligence leaving only the lowest level of life forms, the bacteria, mosses and etc as the survivors.
Climate science unlike most other science disciplines has become a resource greedy, grabbing, passive, non productive,deliberately fear creating branch of science where the only “science” done consists of “studies” as above.
Which unlike say nanotechnology, medicine, physics, mathematics and etc and etc, climate science has not and never has provided any real contribution of any worth to society nor has it demonstrated any evidence of being a useful, viable constructive contribution to society.

1km retreat doesn’t sound like much, given there has been some warming over the last 150 years.
I think they like homing in on this area because they think it is not inhabited by anyone able to contradict what they say. However, there are oral traditions relating to land forms, coastline etc from Melanesian peoples in PNG that match events calculated to have occurred 12,000 years ago. We have some of this documented – maybe we’d better start looking for it.
The west Pacific is where a fair amount of our bad weather comes from, and yes it has been a relatively sleepy dragon in recent years. No reason for complacency of course.
“Extensive new datasets” which they then somehow feed into their crack-brained CO2 models ….
Wondering what “deep convection” is supposed to mean. They have finally discovered it is not all just conduction?

John F. Hultquist

What is available in this post fits with the idea that a large committee cannot write clean and simple text despite having done interesting research. For example,
ocean temperatures in this area may be more sensitive to changes in greenhouse gas levels than previously thought . . .
Who previously thought what and why? [Who’s on first? Look it up!]
And, just how do they think GHGs change the ocean temperature? They write as though the process is simple and direct. And why is the phrase “in this area” thrown in? Do I assume they know other areas where the ocean temperatures are less blah, blah …
Jimbo contributed another and there is more. But like Jimbo, I’m off for now.
Jimbo says:
March 14, 2014 at 6:21 pm

About clicking on that WUWT bookmark:
It is advised that skeptics take a blood pressure pill before any encounter with writings about the climate of Earth.

Mac the Knife

Using a cutting-edge research technique, UCLA researchers have reconstructed the temperature history of a region that plays a major role in determining climate around the world.
Cutting edge…. or cutting corners? Hard to tell, with the paper behind a paywall.
“The tropical Pacific ocean-atmosphere system has been called a sleeping dragon because of how it can influence climate elsewhere,” said lead author Aradhna Tripati, a UCLA assistant professor in the departments of Earth, planetary and space sciences, and atmospheric and oceanic sciences.
Ahhhh, Dragons! The missing heat…. The computer models didn’t include dragons, an essential but little appreciated parameter in global warming models. It seems sooooo obvious now…….

Damian

Remember to stick to and follow your convections. Lol.

Renaldo

Crap, crap, and more crap. I was on Midway Island in 1963. It looked pretty much like it did in 1943. Elevation 3 feet. Guess what? It’s 2014 and the average elevation on Midway Island is 3 feet. Even more to the point, French Frigate Shoals (look it up) is just as much above and below the surface as it was 70 years ago. Please let me know when that beloved
westernmost hawaiian island sinks. I for one will fall off the wagon in desperate grief.

urederra

Oh, Polynesians and their SUVs…That explains everything.

Plausible Deniability

“Most global climate models underestimate the average temperature variations that the region has experienced,” Tripati said, adding that the other models’ simulations may be incomplete or the models are not sensitive enough.
So, they are saying that the models for which we are supposed to bankrupt all the world economies and throw millions and millions of people into poverty may be incomplete.
CLIMATE DENIERS!!!

Patrick

“Renaldo says:
March 14, 2014 at 11:01 pm”
Your post reminded me of this;
http://www.cookislands.travel/cook-islands/rarotonga/boat-cruises/x,1,4309/reef-sub.html
I saw it in 1995 on my way toNew Zealand. It’s still there, still roughly where it was in relation to sea levels when it sunk in 1916.

Perry
thegriss

wws says:
I’m glad to report that my region has warmed considerably over the last 2 weeks. It’s nice”.
Being from the land down under, I would like to confirm that the “climate” has cooled a little over the last few weeks (climate change and all that. y’know).
The “scorchers” that we always get in summer have eased off, and its just downright pleasant.
Fortunately, at this time of year, the ocean water is still warm, and off-shore breezes hold the waves up nicely.
Life is tough down here in Cronulla. 🙂
http://en.wikipedia.org/wiki/Cronulla,_New_South_Wales

thegriss

I would just like to add that the population of Australia has a high percentage of coastal inhabitants.
Anyone older than 15 years old will tell you that the seas haven’t risen that anyone can see, summers are still rather hot sometimes, thank goodness. Spring and Autumn are idyllic.
And in winter, you need a wetsuit.
All these fools preaching “climate change” either grew up in their mum’s basement or were never Aussies to start with.
Nothing has changed.. the climate down here is still REALLY NICE ! 🙂

thegriss

And because I’m on a roll..
All you inner city Melbourne greenie luvlies that are hysterical about climate change.. if you don’t like the few days of the year than Melbourne gets rather warm.. Move to Tasmania..
You can inbreed down there.

john

ROM says:
March 14, 2014 at 9:37 pm
A steady state global climate would lead to stagnation and the eventual very slow extinction of nearly every higher life form as well as intelligence leaving only the lowest level of life forms, the bacteria, mosses and etc as the survivors.
————-
So the meek WILL inherit the earth !!

daddylonglegs

The findings illustrate that the region is very sensitive to climate change and that it has warmed considerably over the last 20,000 years, since the last ice age.
No. The only scientific finding in this work is that SST changed by 4-5 deg C since the last glacial minimum 20kya, instead of 3 C.
The climate has changed.
To describd this as greater sensitivity to climate change is a sign of dysfunctional logic or the deliberate intention to confuse and mislead. It is introducing redundant and fictitious logical clauses.
Observation: your child has grown.
CAGW narrative: your child has become more senstitve to size-change.
Observation: it is raining.
CAGW narrative: this location has become more sensitive to rain-making processses.
It makes no sense except as a deliberate atempt to deceive.

Berényi Péter

Come on. During the Last Glacial Maximum, which ended 19 thousand years ago sea level was 130 m lower. That means the geography of the region was entirely different, there was no Maritime Continent there, but two vast landmasses separated by narrow straits, the southern continent of Sahul, which included present day Tasmania, Australia and New Guinea and the Sunda subcontinent in the north, extending over Java, Sumatra, Borneo, Malay peninsula and the surrounding seabed up to southern China. There was not much room for a warm pool between Sahul &. Sunda, was there? The Indonesian Throughflow must have been pretty restricted as well, so the entire ocean circulation pattern was different in the region.

thegriss says:
March 15, 2014 at 1:51 am X 3
Very very funny and the Sydney Inner City Greens can join the Melbourne Inner City Greens in Tassie for a green luv in.