Image Credit: Carbon Dioxide Information Analysis Center
From CNN with comments below by WUWT regular Just The Facts:
Global warming has propelled Earth’s climate from one of its coldest decades since the last ice age to one of its hottest — in just one century.
A heat spike like this has never happened before, at least not in the last 11,300 years, said climatologist Shaun Marcott, who worked on a new study on global temperatures going back that far.
“If any period in time had a sustained temperature change similar to what we have today, we would have certainly seen that in our record,” he said. It is a good indicator of just how fast man-made climate change has progressed.
A century is a very short period of time for such a spike.
It’s supposed to be cold
The Earth was very cold at the turn of the 20th century. The decade from 1900 to 1909 was colder than 95% of the last 11,300 years, the study found.
Fast forward to the turn of the 21st century, and the opposite occurs. Between 2000 and 2009, it was hotter than about 75% of the last 11,300 years.
If not for man-made influences, the Earth would be in a very cold phase right now and getting even colder, according the joint study by Oregon State University and Harvard University. Marcott was the lead author of the report on its results. Read More
Here is the National Science Foundation article that the CNN article appears to be based upon and here is the paper, A Reconstruction of Regional and Global Temperature for the Past 11,300 Years, published in Science today. This is the abstract:
Surface temperature reconstructions of the past 1500 years suggest that recent warming is unprecedented in that time. Here we provide a broader perspective by reconstructing regional and global temperature anomalies for the past 11,300 years from 73 globally distributed records. Early Holocene (10,000 to 5000 years ago) warmth is followed by ~0.7°C cooling through the middle to late Holocene (<5000 years ago), culminating in the coolest temperatures of the Holocene during the Little Ice Age, about 200 years ago. This cooling is largely associated with ~2°C change in the North Atlantic. Current global temperatures of the past decade have not yet exceeded peak interglacial values but are warmer than during ~75% of the Holocene temperature history. Intergovernmental Panel on Climate Change model projections for 2100 exceed the full distribution of Holocene temperature under all plausible greenhouse gas emission scenarios.
While the warming of the second half of the 21st century, and its causes, are the subject of vigorous debate, the fundamentally erroneous element of the CNN article above is the attribution of warming from the first half of the 21st century to human influence. Per Overpeck et. al 1997:
“Together, they indicate that the Arctic has warmed up to 1.5°C since 1850 – the coolest interval of the Arctic “Little Ice Age.” Much of the recent Arctic warming took place between 1850 and 1920, most likely due to natural processes”
If you look at anthropogenic CO2 emissions;
it is apparent that the anthropogenic contribution to CO2 concentrations was minimal prior to 1945, thus attribution of the warming that occurred prior to 1945;
to “man-made influences”, is fundamentally erroneous. CNN should correct this error in their article.
For further information on Earth’s paleoclimate please visit WUWT’s under construction Paleoclimate Reference Page.
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It would be nice if they had compared the most recent warming to previous Daansgard-Oeschger events and to the end of the Younger Dryas. In the article the charts all eliminate the major climatic hiccups of the Holocene. They compare the “average” cooling of the last 5,000 years to the absolute warming of the last 150, then talk about the rate of warming. The last 5,000 years takes in the Minoan, Roman and Medieval warm periods, all of which were as warm as, or warmer than the present. It is also fairly clear that the warming does not correlate with anthropic CO2 emissions.
So why am I still freezing to death?
James Abbott says: March 8, 2013 at 10:25 am
National Oceanic and Atmospheric Administration (NOAA) – Earth System Research Laboratory (ESRL) – Click the pic to view at source[/caption]
“It is apparent that the anthropogenic contribution to CO2 concentrations was minimal prior to 1945, thus attribution of the warming that occurred prior to 1945; to “man-made influences”, is fundamentally erroneous. CNN should correct this error in their article.”
Is that annual emissions or atmospheric concentration ? – 2 different things.
The “anthropogenic contribution” and the chart;
http://cdiac.esd.ornl.gov/trends/emis/glo.html
are emissions;
http://cdiac.esd.ornl.gov/trends/emis/meth_reg.html
which would thus impact CO2 concentration, i.e.:
[caption id="" align="alignnone" width="600"]
By 1959, when the Mauna Loa sequence starts, concentration was 316ppm, which was already about 14% above pre-industrial levels.
We simply do not know the extent of warming (if any) due to early carbon emissions so to say that the original article is “fundamentally erroneous” is …. fundamentally erroneous.
The article states “A century is a very short period of time for such a spike.” … “If not for man-made influences, the Earth would be in a very cold phase right now and getting even colder”. This implies that the warming over the last century, including over the first half of the century, occurred because of man-made influences. Drawing a relationship between anthropogenic CO2 and warming in the second half of the 20th century warming is tenuous at best and potentially erroneous, however there is no substantive relationship between anthropogenic CO2 emissions and the warming in the first half of the 20th century, thus implying that there is is fundamentally erroneous.
As mentioned in the previous article about this paper the resolution is not adequate to discuss recent temperatures. I suspect they factored in the adjusted temperature data and are now calling that the results of the study. Not quite as bad as Mann but just as bogus.
“A heat spike like this has never happened before, at least not in the last 11,300 years, said climatologist Shaun Marcott, who worked on a new study on global temperatures going back that far.”
What a complete and utter tool, or is it fool? The warming from 1910 to 1940 had the same slope as the one from 1980 to 2000 – which ended in 2000.
Stupid or evil? Maybe both.
Although not very scientific, it is worth comparing the rise in CO2 emissions over the last 110 years with the rise in average surface temperatures. My reckoning is that that although both rose significantly since 1900, the match the rise is not close at all.
I am a novice compared to many of you. Is the Met chart claiming they know the worldwide land temperature in 1850 to within one degree C? If so, how do they determine that accuracy?
“For further information on Earth’s paleoclimate please visit WUWT’s under construction Paleoclimate Reference Page.”
==========
Looks like the beginnings of another great page.
I just put it on my reading list, for leisurely perusal in the near future.
Thanks, “justthefactswuwt”.
It’s supposed to be cold? Who the hell does he think he is? God?
Where’s that comparison between model runs with and without GHG forcings included, that shows that even by the AGW hypothesis, human effects on warming didn’t begin until 1950? I’ve been looking for it lately, and can’t find it. It was created to show that recent warming can’t be explained except by GHG forcings, but it also demonstrates that warming earlier than 1950 couldn’t have been caused by changes in GHGs.
Arctic temperature and CO2 compared
http://www.vukcevic.talktalk.net/CO2-Arc.htm
But actually one of the report’s authors endorses that interpretation:
you will always get an exaggerated movement when you change the scale, in that graph the large movements are filtered out to give a mean,the last movements havenot been averaged, there will be many such spikes (up and down)that have been filtered out.
I fully expect to see more and more of this, ever since Dear Leader gave his “you’re stuck with me for another 4yrs, and here’s what I’m going to focus on” speech. He essentially politically validated and re-enabled everything that’s been shot down regarding climate change/C02 over the past 4 yrs, and pumped some serious air into the almost flat tires of that movement.
I fear we ain’t seen nuttin yet.
Jim
That last MetOffice graph looks like it uses GISS’s massively adjusted trend manufactured pretext for data.
You know, the ex-data that has had everything before the satellite data era dropped down by nearly a whole degree..
Where is the mid 1930’s peak.. gone, just like Mann disappeared the Medieval period.
The whole graph is a LIE !!
The Overpeck graph is out of date; the North Pole has warmed by 0.8 C since the end of 1997, according to UAH data for the lower troposphere….
If not for man-made influences…
=======
I would be more inclined to agree with this…..if they are talking about UHI, deforesting, etc
….I’m not convinced man could ever add enough CO2 to the atmosphere to make a difference
Just ask any pot grower that jacks the CO2 levels up to 1200-1500 in their closet…only to have a hand full of plants drop it back down to where it’s limiting again in less than 24 hours……
Planted fish aquarium…..again inject CO2 or it’s limiting
Closed greenhouses…..again inject CO2 or it’s limiting
Bacteria….
and on and on
With all the reservoirs for CO2……..
The science of climate change is interesting and fun…..I’m not convinced at all that man can add enough CO2 to make a difference….and it would have to be a special CO2….one that stays in the atmosphere not used by biology
The post says, “…the anthropogenic contribution to CO2 concentrations was minimal prior to 1945.”
This isn’t true. When you include land use changes, you find that global anthropogenic carbon emissions were 126 GtC by 1945, or 23% of such CO2 emissions to-date.
Sources:
http://cdiac.ornl.gov/trends/emis/tre_glob.html
http://cdiac.ornl.gov/trends/landuse/houghton/1850-2005.txt
R. Shearer says: “So it’s possible that manmade global warming has slowed or even prevented the onset of the next ice age. That might be a good thing to know.”
We have already prevented the next ice age (and probably the one after that) — the problem is we’ve overshot the mark considerably. CO2 concentration should have dropped to about 250 ppmv by now, had the LIA continued, and probably just 280 ppmv would have avoided the next ice age (Tzedakis et al, Nat Geo 2012). Instead we will swing wildly in the other direction.
REPLY: Bloviating phantom: you really should demonstrate how that increase in CO2 has “prevented the next ice age” – show your work – Anthony
Cement manufacture is always cited as a significant emitter of CO2. Calcination of limestone, a prime ingredient in portland cement, emits ~40kg of CO2 per 100kg of limestone – 60% of the CO2 from the process – quite a lot! However, as the cement ages it recaptures this CO2. Similarly plasters, and other products using burnt lime recapture their calcined CO2.
http://www.dti.dk/reports-on-co2-uptake-from-the-carbonation-of-concrete/guidelines/18487,5
Can we please remove this miraculous building material off the list of things that are supposed to be killing us with CO2. A couple of other facts about cement – it makes up only 10 to 14% of concrete, it has high strength and no competing building material has such a long life. Other materials would require replacement more frequently and ultimately would result in greater net CO2 emissions in the production and construction process.
Why oh why do these high schoolish scientists not look for corroboration from other sources. It’s fine to look at 70-odd proxies for their study (that many thermometers today wouldn’t be acceptable it seems) but there is so much out there that they could cite and possibly even strengthen their analysis. To be giving statistics on what percentage of time something has been above and below certain temperatures is totally incompetent. Each point on their temp line is a 120 year bundle (avg), except for the recent observed temperature record – try bundling the last 120 years into an average an see where it plots on your graph. Meanwhile, they move along, completely oblivious of some irrefutable observations on former climate conditions – like the Arctic having ~50% less ice coverage 5000 years ago, evidenced by datable driftwood on a wave formed sandy beach on the north coast of Greenland that hasn’t seen open water centuries.
http://www.iceagenow.com/Surprise-Arctic_tipping_point_not_even_close.htm
“By analyzing and carbon-dating ancient pieces of driftwood in Northern Greenland, the team has found evidence that ice levels were about 50% lower some 5,000 years ago.”
1850 was the end of the mini ice age, an age of famine and pestilence. Do the warmists wish us to return to these days? In the three warm periods in recorded human history, the Minoan, Roman and Medieval , the earth was warmer and wetter. Life, both human and natural flourished. To say we are at the warmest in 11,000 years is a LIE. During the Medieval warm period, grapes were being grown as far north as Scotland.
What hight of arrogance to assume that humans are responsible and CO2 in particular causes this, when natural variability in the past could not have been caused by CO2. It is well known that CO2 is plant food. Below about 200ppm, plant life stalls. Hello warmists, plants LOVE extra CO2. Yields are higher and stomatal conductivity(transpiration and water use) is lower.
Perhaps humans were put on this earth to recycle the carbon buried beneath the earth during the Carboniferous Era .
The recent avalanche of new hockey sticks and worse-than-we-thoughts is aimed to meet the deadline of the new IPCC report. Remember when inconvenient truths about observations and forecasts not matching and that maybe the sun has something to do with the climate was mused about in an unauthorized draft of the coming report. They responded that they will be including supportive drivel published up until May 2013.
Not sayin’ I agree with the NSF study or the CNN spin, but the NSF study is about “regional and global temps” and the Overpeck study cited in rebuttal appears to be about arctic temps only. Is this not a problem? What am I missing?
The only thing these authors were attempting to do is ensure their careers are sufficiently lengthened to last into retirement, plus gain a substantial amount of fame and notoriety along the way.
Us folk here spouting facts have no real meaning.
In Maine we call it “Pissin’ against the tide”. And the tides are 8-12ft, depending on where you are. That being said, you’ve gotta go somewhere…
Jim