UPDATE: see this new article on the issue,
“Ice cores from Summit show that melting events of this type occur about once every 150 years on average. With the last one happening in 1889, this event is right on time,” says Lora Koenig, a Goddard glaciologist and a member of the research team analyzing the satellite data.
Extent of surface melt over Greenland’s ice sheet on July 8 (left) and July 12 (right). Measurements from three satellites showed that on July 8, about 40 percent of the ice sheet had undergone thawing at or near the surface. In just a few days, the melting had dramatically accelerated and an estimated 97 percent of the ice sheet surface had thawed by July 12. In the image, the areas classified as “probable melt” (light pink) correspond to those sites where at least one satellite detected surface melting. The areas classified as “melt” (dark pink) correspond to sites where two or three satellites detected surface melting. The satellites are measuring different physical properties at different scales and are passing over Greenland at different times. As a whole, they provide a picture of an extreme melt event about which scientists are very confident. Credit: Nicolo E. DiGirolamo, SSAI/NASA GSFC, and Jesse Allen, NASA Earth Observatory
I covered this over the weekend when Bill McKibben started wailing about the albedo going off the charts. I thought it might be soot related. The PR below and quote above is from NASA Goddard. I had to laugh at the title of their press release, where they cite “Unprecedented Greenland Ice Sheet Surface Melt”, then contradict themselves when the main researcher goes on to say “melting events of this type occur about once every 150 years on average. With the last one happening in 1889“. Do these guys even read their own press releases? Climatologist Pat Michaels concurs saying: “Apparently NASA should start distributing dictionaries to the authors of its press releases.”
I’ve sent off a note to the NASA writer, seen here. Maybe she’ll get the headline fixed.
That, and they seem surprised that the Greenland ice sheet would suddenly start melting in summer. Though, not every part of the ice sheet is melting right now, so perhaps their calibrations might be a bit off:
There may have been a brief few days of melt, but it appears to be over:
Satellites See Unprecedented Greenland Ice Sheet Surface Melt
For several days this month, Greenland’s surface ice cover melted over a larger area than at any time in more than 30 years of satellite observations. Nearly the entire ice cover of Greenland, from its thin, low-lying coastal edges to its two-mile-thick center, experienced some degree of melting at its surface, according to measurements from three independent satellites analyzed by NASA and university scientists.
On average in the summer, about half of the surface of Greenland’s ice sheet naturally melts. At high elevations, most of that melt water quickly refreezes in place. Near the coast, some of the melt water is retained by the ice sheet and the rest is lost to the ocean. But this year the extent of ice melting at or near the surface jumped dramatically. According to satellite data, an estimated 97 percent of the ice sheet surface thawed at some point in mid-July.
Researchers have not yet determined whether this extensive melt event will affect the overall volume of ice loss this summer and contribute to sea level rise.
“The Greenland ice sheet is a vast area with a varied history of change. This event, combined with other natural but uncommon phenomena, such as the large calving event last week on Petermann Glacier, are part of a complex story,” said Tom Wagner, NASA’s cryosphere program manager in Washington. “Satellite observations are helping us understand how events like these may relate to one another as well as to the broader climate system.”
Son Nghiem of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., was analyzing radar data from the Indian Space Research Organisation’s (ISRO) Oceansat-2 satellite last week when he noticed that most of Greenland appeared to have undergone surface melting on July 12. Nghiem said, “This was so extraordinary that at first I questioned the result: was this real or was it due to a data error?”
Nghiem consulted with Dorothy Hall at NASA’s Goddard Space Flight Center in Greenbelt, Md. Hall studies the surface temperature of Greenland using the Moderate-resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra and Aqua satellites. She confirmed that MODIS showed unusually high temperatures and that melt was extensive over the ice sheet surface.
Thomas Mote, a climatologist at the University of Georgia, Athens, Ga; and Marco Tedesco of City University of New York also confirmed the melt seen by Oceansat-2 and MODIS with passive-microwave satellite data from the Special Sensor Microwave Imager/Sounder on a U.S. Air Force meteorological satellite.
The melting spread quickly. Melt maps derived from the three satellites showed that on July 8, about 40 percent of the ice sheet’s surface had melted. By July 12, 97 percent had melted.
This extreme melt event coincided with an unusually strong ridge of warm air, or a heat dome, over Greenland. The ridge was one of a series that has dominated Greenland’s weather since the end of May. “Each successive ridge has been stronger than the previous one,” said Mote. This latest heat dome started to move over Greenland on July 8, and then parked itself over the ice sheet about three days later. By July 16, it had begun to dissipate.
Even the area around Summit Station in central Greenland, which at 2 miles above sea level is near the highest point of the ice sheet, showed signs of melting. Such pronounced melting at Summit and across the ice sheet has not occurred since 1889, according to ice cores analyzed by Kaitlin Keegan at Dartmouth College in Hanover, N.H. A National Oceanic and Atmospheric Administration weather station at Summit confirmed air temperatures hovered above or within a degree of freezing for several hours July 11-12.
“Ice cores from Summit show that melting events of this type occur about once every 150 years on average. With the last one happening in 1889, this event is right on time,” says Lora Koenig, a Goddard glaciologist and a member of the research team analyzing the satellite data. “But if we continue to observe melting events like this in upcoming years, it will be worrisome.”
Nghiem’s finding while analyzing Oceansat-2 data was the kind of benefit that NASA and ISRO had hoped to stimulate when they signed an agreement in March 2012 to cooperate on Oceansat-2 by sharing data.
============================================
h/t to WUWT reader Ole Heinrich
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From Gail Combs on July 25, 2012 at 10:05 am:
Gail, your link is this WUWT article. I found that’s something that wordpress does if you miss a doublequote in the “href=” link, defaults to the page the link is posted on. I’ve noticed you’ve been doing that a lot lately, when your links show up with the “recently viewed” coloration and I check them.
You’re good, you can do better. Please doublecheck before posting. Thank you.
Kevin MacDonald,
I see what you did there. You cherry-picked increasingly short term trends to make believe temperatures are accelerating. They are not. And the same thing has happened before, irregardless of CO2 levels.
“Everyone has the right to be stupid, but comrade MacDonald abuses the privilege.”
~ Leon Trotsky
And Ric Werme, you are correct as usual. Most of the claims of recently rising temperatures are based on noise. This is the right way to look at the global warming scare.
Wrong!
You can’t even read a graph, The trends all cover the same time span, they show centennial trends since the end of the LIA and the centennial rate of warming has doubled.
Ooh, an ad hom, first reply and you’ve immediately segued from basic factual errors to logical fallacies. Well done!
Smokey says:
July 24, 2012 at 3:49 pm
“ignoring the fact that it is 15 years with no warming”
This must be the graph you use to reach that conclusion.
http://data.giss.nasa.gov/gistemp/graphs_v3/Fig.A2.gif
From the graph:-
Date Temp. anomaly Change to 2011
1996 +0.29 0.51 – 0.29 = +0.20
1997 +0.41 0.51 – 0.41 = +0.10
1998 +0.58 0.51 – 0.58 = -0.07
1999 +0.33 0.51 – 0.33 = +0.18
2000 +0.35 0.51 – 0.35 = +0.16
2010 +0.62
2011 0.51
You, sir, have been caught cherrypicking data.
You were most insistant that the measured temperature change for recent years counted from 1998.
It is surely not a coincidence that your chosen year in the latter 1990s is the only one giving a negative temperature change to 2011.
This deliberate obfuscation is exactly the sort of data misuse that I see sceptics complaining about. How do you expect to be taken seriously in debate when you cannot not even meet the standards you would demand of your opponents.
Kevin MacDonald,
The Trotsky quote was poking fun, my bad. But you are still cherry-picking, as your newest WFT graph shows. It is you who has a problem with reading graphs. Using your zero baseline graphs always produces a fake artifact. See my previous charts to understand why.
And re: Ric Werme’s comment about Tibetan tree rings, see here;
Liu Yu, Director of Earth Environment Institute of the Chinese Academy of Sciences, was interviewed about his paper by the South China Morning Post (Dec 4, 2011):
Where did you find trees more than 2,000 years old in a country with a long history of systematic logging? I need luck to find a tree more than 100 years old in the lowlands. But on some mountains of the Tibetan Plateau, where the altitude reaches up to 4,000 metres, I have run into forest after forest of Qilian junipers that have remained undisturbed for thousands of years.
How does a tree survive in that kind of harsh environment for so long? The Qilian juniper is one of the oldest surviving tree species on earth. In the high altitude of the eastern Tibetan Plateau, where poor soil, little rainfall and low temperatures make it impossible for other trees to survive, the juniper has perfectly adapted to the harsh environment by growing very slowly. We recently found one that is close to 2,000 years old, but less than 8 metres tall. In the study of tree rings, slow-growing trees provide information on variations in climate over a long period. Qilian junipers grow only in China.
Is the study of tree rings popular in China? Chinese researchers have studied tree rings for more than seven decades, and some scientists have produced original studies containing a trove of important data on the climate. But due to historical reasons, their research methods did not quite fit with international mainstream thinking, and therefore not widely recognised. Since the 1990s, as climate change has become a political and diplomatic issue, the study of tree rings has received increased government funding, allowing Chinese researchers to use the best tools and methods and produce well-received results.
Are the field trips fun? To collect samples, we sometimes need to dance with death. At altitudes of more than 3,500 metres above sea level, my research team has to combat low air pressure, a lack of oxygen, headaches and sometimes life-threatening illnesses. The best Qilian junipers for our purposes often stand alone on a cliff, where they can be fully exposed to the elements. We have to watch our step when approaching such trees. Some researchers from overseas have slipped and died in less-perilous situations. Most virgin forests of Qilian junipers are in areas inaccessible by road, and are barely, if ever, visited by humans. The remoteness turned each of my more than 20 data-collection trips over the past 10 years into unforgettable adventures. Standing so high up, with an ancient tree, one has the opportunity to enjoy some of the most breathtaking landscapes on earth.
Do you need to cut down a tree to take samples No, we do not cut down trees. Once a tree is selected, we use a long, fine tube similar to a chopstick to bore through the trunk and reach the core. It’s standard practice used by scientists for a long time and does not cause the tree any serious damage. In the laboratory, all the samples must be polished with sandpaper. The work is time-consuming because the samples cannot be used for measurement until they are smooth enough that, when put under a microscope, we can see a perfect outline of their cells.
What do you do with the data? Using a set of scientific techniques, we measure the width of the rings and convert the variations into changes in annual temperatures. We have published two papers in the English versions of Science in China – Series D: Earth Sciences and in the Chinese Science Bulletin.
What have tree rings told us about climate change over the last two millennia? Popular belief is that industrialisation has led to the fastest rate of warming witnessed by humans; that we are at the warmest time of the modern era; and that we are causing global warming by emitting carbon dioxide into the atmosphere. None of that fits the records in tree rings. In northern China, the warmest period occurred from AD401-413, which had an annual mean temperature 0.16 degrees Celsius higher than today’s. Other periods, including 604-609, 864-882 and 965-994 had temperatures higher than in recent decades. Our results are supported by historical documents from the period. Archaeological records in Loulan , Xinjiang , show that pomegranate, a fruit rich in vitamin C, was used as currency during the Eastern Jin dynasty (AD317-420). The fruit could not possibly have appeared in northern China without a climate much warmer than today’s. And we are not experiencing the most dramatic climate change in recent history, either. Over the past 2,485 years, the biggest climate change took place during the Eastern Jin dynasty. The period had two stages, with the temperature plummeting first and then soaring. In the warming period, the mean temperature [in the Tibetan Plateau region] increased suddenly from 1.66 degrees to 2.67 degrees in 30 years. In the cooling period, the mean temperature dropped to below that of the Little Ice Age [an abnormally cold period that lasted from about 1550 to 1850]. The coldest years, with a mean temperature of 1.38 degrees, occurred from 362-369, and the temperature was about 1.5 degrees lower than the mean temperature of the late 20th century.
So what causes climate change? We believe that the sun and atmospheric circulations play a vital, if not decisive, role in this. The millennial cycle of solar activity determines the long-term trends of temperature variations. Almost all sunspot minimums [periods of sometimes several decades when sunspots become rare] correspond with low-temperature intervals. Meanwhile, atmospheric circulations affect temperature changes from decade to decade. To quote Professor Zhu Kezhen , the father of climate change studies in China: “The big changes in the earth’s climate have been controlled by solar radiation, but the small changes by atmospheric circulation.”
Can tree-ring records tell us anything about the future? Our results show that the temperature continued to increase until 2006, and will now decrease until about 2068. After 2068, the temperature will increase again until 2088.
Do you think your research will help Beijing gain ground in climate negotiations? I am a scientist, and I know nothing about politics. But the climate- change debate, in my opinion, has more political significance than scientific. Diplomats can sit at negotiating tables talking about carbon caps while scientists have not reached an agreement on the role of carbon dioxide in global warming. But political decisions must be based on sound scientific foundation, or they will be useless, if not dangerous.
Entropic,
Since I smoked you out, you are getting a bit defensive:
Choose 2002 then, and see what happens. Even less warming. None, in fact.
You are losing the debate, Entropic. Go back to RealClimate where you belong.
From Kevin MacDonald on July 25, 2012 at 4:15 pm:
Cool your jets. You switched graphs between your earlier post and this one. Complete url from previous post:
http://www.woodfortrees.org/plot/hadcrut3vgl/from:1860/to:1960/trend/plot/hadcrut3vgl/from:1865/to:1965/trend/plot/hadcrut3vgl/from:1870/to:1970/trend/plot/hadcrut3vgl/from:1890/to:1990/trend/plot/hadcrut3vgl/from:1895/to:1995/trend/plot/hadcrut3vgl/from:1900/to:2000/trend/plot/hadcrut3vgl/from:1905/to:2005/trend/plot/hadcrut3vgl/from:1910/to:2010/trend/plot/hadcrut3vgl/from:1860/to:2010
Last element is 1860 to 2010, only 50 years long.
Now let’s shorten up that last graph to 50 year periods, starting with 1901-51 and ending in 1961-2011: graph.
Looks a lot different now, doesn’t it? Voila, we’ve discovered the effect of the PDO. Positive phase with high rates of warming, negative phase with greatly reduced rates, then positive again and a return to high rates.
And where is the “acceleration in warming”? When the 1998 Super El-Nino gets worked into the trends. And even then, the steepest earliest rate is the first, 1901-51, 0.0100724 per year (click on “Raw Data”). The first with 1998 included, 1951-2001, is slightly less, 0.00998399 per year, effectively the same.
The “acceleration” comes as more of the step change in temperatures due to 1998 gets incorporated into the rates. It’s not real.
Move along now, nothing happening here….
Unprecedented = 150 years average cyclicality
I wonder what the cycles are attributed to ?
kadaka (KD Knoebel) says:
July 25, 2012 at 7:31 pm
From Kevin MacDonald on July 25, 2012 at 4:15 pm:
Wrong!
You can’t even read a graph, The trends all cover the same time span, they show centennial trends since the end of the LIA and the centennial rate of warming has doubled.
Cool your jets. You switched graphs between your earlier post and this one. Complete url from previous post:
http://www.woodfortrees.org/plot/hadcrut3vgl/from:1860/to:1960/trend/plot/hadcrut3vgl/from:1865/to:1965/trend/plot/hadcrut3vgl/from:1870/to:1970/trend/plot/hadcrut3vgl/from:1890/to:1990/trend/plot/hadcrut3vgl/from:1895/to:1995/trend/plot/hadcrut3vgl/from:1900/to:2000/trend/plot/hadcrut3vgl/from:1905/to:2005/trend/plot/hadcrut3vgl/from:1910/to:2010/trend/plot/hadcrut3vgl/from:1860/to:2010
Last element is 1860 to 2010, only 50 years long.
Oops, forgot to save the edit. Let’s try that again….
kadaka (KD Knoebel) says:
July 25, 2012 at 7:31 pm
150 years, not trend – it’s the full temperature record and is the background to all the trend lines.
Why is history as recorded by newspapers being ignored? Remember, newspapers used to report relevant, important facts and scientific advancements instead of the puerile lifestyle entertainment that dominates our modern media.
Newspaper stories were hinting at a warming climate, particularly the Arctic and Greenland, in the late 1800s and into the 1900s. For example, from the Examiner newspaper dated 26 May 1906 (http://trove.nla.gov.au/ndp/del/article/38087689):
“IS THE EARTH GETTING WARMER? That the earth is growing temporarily warmer is shown by the mountain glaciers. These are made by varying temperature and moisture to increase and diminish in size during periods of years that may be found to be more or less regular cycles, and a period of quite general decrease began about 45 years ago. This has continued, with many local interruptions, as in the case of Glacier Blanc, which advanced from 1889 to 1896. The latest report includes 90 glaciers in the Swiss Alps, in Norway, Greenland, the Caucasus, the Pamir, the North West United States, Western Canada. and Africa, and practically all are growing smaller. In the Savoy Alps and the Pyrenees small glaciers have quite disappeared.”
Or extracts from The Advertiser dated 4 April 1923 (http://trove.nla.gov.au/ndp/del/article/74081229):
“Reports from fishermen, seal hunters, and explorers who sail the seas around Spitzbergen and the eastern Arctic all point to a radical change in climatic conditions, with hitherto unheard-of high temperatures on that part of the earth’s surface.”
“The United States Consul at Bergen, Norway, Mr. Ifft, also reports the recent extraordinary warmth in the Arctic. He quotes incidentally the statements of Captain Martin Ingebrigtsen, a mariner who has sailed those seas for 51 years. The captain says that he first noted an unusual warmth in 1918; and since then temperatures have risen steadily higher. Today the eastern Arctic is ‘hardly recognisable as the same region of 1868 to 1917’.”
“Many of the old landmarks are greatly altered, or no longer exist. Where formerly there were great masses of ice, these have melted away, leaving behind them accumulations of earth and stones such as geologists call ‘moraines.’ At many points where glaciers extended far into the sea half a dozen years ago they have now entirely disappeared.”
There are dozens of examples at http://www.waclimate.net/climate-history.html with reports in those days suspecting that global warming began around 1850.
Why is history as recorded by newspapers being ignored? Remember, newspapers used to report relevant, important facts and scientific advancements instead of the puerile lifestyle entertainment that dominates our modern media.
Newspaper stories were hinting at a warming climate, particularly the Arctic and Greenland, in the late 1800s and into the 1900s. For example, from the Examiner newspaper dated 26 May 1906 (http://trove.nla.gov.au/ndp/del/article/38087689):
”IS THE EARTH GETTING WARMER? That the earth is growing temporarily warmer is shown by the mountain glaciers. These are made by varying temperature and moisture to increase and diminish in size during periods of years that may be found to be more or less regular cycles, and a period of quite general decrease began about 45 years ago. This has continued, with many local interruptions, as in the case of Glacier Blanc, which advanced from 1889 to 1896. The latest report includes 90 glaciers in the Swiss Alps, in Norway, Greenland, the Caucasus, the Pamir, the North West United States, Western Canada. and Africa, and practically all are growing smaller. In the Savoy Alps and the Pyrenees small glaciers have quite disappeared.”
Or extracts from The Advertiser dated 4 April 1923 (http://trove.nla.gov.au/ndp/del/article/74081229):
”Reports from fishermen, seal hunters, and explorers who sail the seas around Spitzbergen and the eastern Arctic all point to a radical change in climatic conditions, with hitherto unheard-of high temperatures on that part of the earth’s surface.”
”The United States Consul at Bergen, Norway, Mr. Ifft, also reports the recent extraordinary warmth in the Arctic. He quotes incidentally the statements of Captain Martin Ingebrigtsen, a mariner who has sailed those seas for 51 years. The captain says that he first noted an unusual warmth in 1918; and since then temperatures have risen steadily higher. Today the eastern Arctic is ’hardly recognisable as the same region of 1868 to 1917’.”
”Many of the old landmarks are greatly altered, or no longer exist. Where formerly there were great masses of ice, these have melted away, leaving behind them accumulations of earth and stones such as geologists call ’moraines.’ At many points where glaciers extended far into the sea half a dozen years ago they have now entirely disappeared.”
There are dozens of examples at http://www.waclimate.net/climate-history.html with reports in those days suspecting that global warming began around 1850.
@ur momisugly Ric Werme on July 25, 2012 at 9:56 pm:
True. My mistake, should have caught it.
I’m going to bed now.
What’s required is to criminallise headlines which are in direct contradiction to the body of the article.
That means if you lie in a headline, you can only do it if you lie in a consistent manner in the main body text.
Would be rather difficult for extreme right wing newspapers and websites, that, of course.
They’d be in court every day.
So you’d have to have a ‘three strikes and you’re out!’ rule for the media too.
Three ridiculous lies and you’re shut down.
Soon clear up the cesspit of lying, distortions and chicaneries going on, wouldn’t it?
What would the investment gurus do with their time then, eh??
Smokey says:
July 25, 2012 at 4:49 pm
So you’re now in favor of Tree Rings when they support your conclusion but you’re against them when Mann uses them? Cognitive bias is an interesting thing isn’t it… Tell me – why is this study any more reliable than any other tree ring study? Did they run into divergence? Which detrending technique is used? It’s funny that when you find something that you wanna see you end up supporting it – if they said CO2 has a major role you’d just say the study was a garbage tree ring study. I’m right about this.
@ur momisugly Ric Werme on July 25, 2012 at 9:56 pm:
Although it’s not “the full temperature record” as HADCRUT3, “variance-adjusted global mean” as was selected, goes back to 1850, not 1860:
http://www.woodfortrees.org/data/hadcrut3vgl
Which I find suspicious as NCDC GHCN only goes back to 1880:
Datasets here near bottom: http://www.ncdc.noaa.gov/cmb-faq/anomalies.php
Select equivalent dataset, The Monthly Global (land and ocean combined into an anomaly) Index (degrees C)
Thus the temperature “data” in HADCRUT3 from 1850 to 1879 seems questionable at best and that range should be avoided without an overriding reason to use it.
Now I’m going to bed now.
Maybe above zero centigrade at Summit is more common in June..
http://www.tutiempo.net/en/Climate/SUMMIT/06-2003/44160.htm
http://www.tutiempo.net/en/Climate/SUMMIT/06-2004/44160.htm
Wrong!
The terms of reference were yours:
Smokey says:
July 25, 2012 at 5:02 pm
Entropic,
Since I smoked you out, you are getting a bit defensive:
“You were most insistant [sic] that the measured temperature change for recent years counted from 1998.
It is surely not a coincidence that your chosen year in the latter 1990s is the only one giving a negative temperature change to 2011.”
Choose 2002 then, and see what happens. Even less warming. None, in fact.
You are losing the debate, Entropic. Go back to RealClimate where you belong.
You have helped make my point. By choosing dates to suit, you can make a case for cooling, warming or stasis, all from the same data. It rather makes the whole exercise pointless arm waving.
Why go back to Realclimate where people agree with me? This is much more fun! I’ve more geniune discussion points here than my limited time can address.
Rather than incestuous agreement with other sceptics here, you, Smokey, and others should be on Realclimate arguing your case against genuine opposition.
[REPLY: Nice try, Entropic, but you are aware that the moderation policies at those other sites are not as, uhhh, liberal and conducive to fair, comprehensive discussion than here at WUWT. That’s why you are here, to argue your case against genuine opposition, which you can’t get at Real Climate. -REP]
Just a reminder:
1. NULL HYPOTHESIS: Statistics the residual hypothesis if the alternative hypothesis tested against it fails to achieve a predetermined significance level.
2.ALTERNATIVE HYPOTHESIS: Statistics the hypothesis that given data do not conform with a given null hypothesis: the null hypothesis is accepted only if its probability exceeds a predetermined significance level.
3. Statistics the theory, methods, and practice of testing a hypothesis concerning the parameters of a population distribution (the null hypothesis) against another (the alternative hypothesis) which will be accepted only if its probability exceeds a predetermined significance level, generally on the basis of statistics derived from random sampling from the given population Compare statistical inference.
Skeptics put the freeze on NASA ‘hot air’ about Greenland ice
Here it seems there is no place for two issues to discuss:
1. The amount of carbon dioxide in the current situation is not alarming. Yes, in future, this value may change for any reason.
2. Some natural events are reversible. This could be due to their oscillatory nature.
The important thing was that in a short time 40% of Greenland ice was melted.
Only the combination of soot and solar radiation could cause such dramatic effects.
@ur momisugly Kevin MacDonald on July 26, 2012 at 5:47 am:
Nah, you’re still cherrypicking. Or perhaps you just don’t understand the mistake.
The effect of the Pacific Decadal Oscillation on the temperature record is obvious. It’s approximately a 60 year cycle, which includes one positive and one negative phase. By choosing a 100 year span for the trends, your most recent trend, 1911-2011, incorporates the positive phase that just ended, the preceeding negative phase, and the positive phase before that. Thus the appearance of accelerating warming was built-in to your selection.
So examine the rates on a 60-yr span: graph.
Again, the first period to incorporate the 1998 Super-El Nino, in this case 1941-2001 at 0.00697957 per year, is beaten by earlier periods, like 1891-1951 at 0.00725121 per year, and 1901-1961 at 0.00765395 per year, and 1906-1966 at 0.0070212 per year. The “acceleration” comes from incorporating more of the temperatures after the 1998 step change in global temperatures.
Also, while not the best of presentations as ever-shorter periods are used, the trends from 1998 to now (end of 2011) should be examined: graph.
Starting in 2001 the trend went negative according to HADCRUT3. Thus it sure looks to me like cooling from 2001 to 2011, not warming.
[REPLY: Nice try, Entropic, but you are aware that the moderation policies at those other sites are not as, uhhh, liberal and conducive to fair, comprehensive discussion than here at WUWT. That’s why you are here, to argue your case against genuine opposition, which you can’t get at Real Climate. -REP]
Perhaps you should tighten your moderation policy. A lot of the “evidence” presented here would never pass peer review, regardless of which side of the debate it supported.
Could you suggest the best way of compiling data tables in posts here. The word processor collapsed my last table, at July 25th 4.43pm, against the left margin.
[REPLY: Our commenters are quite capable of exposing shonky evidence for what it is and have no compunction doing so. Many are emminently qualified to do so. Exposing bad ideas is as much a service as presenting good ideas. WUWT moderators don’t need to be the arbiters of what is good or bad science.
As for your table problem, I have the same problem. Perhaps one of our commenters can offer a solution. -REP]
Mike says:
July 25, 2012 at 9:52 pm
Unprecedented = 150 years average cyclicality
I wonder what the cycles are attributed to ?
I doubt its a 150 year cycle, just a weather event which shows in the ice core about 15 times in 4,000 years . You might get none for a milennium and then two in 100 years. Phil summed it up well:-
The rate of occurrence there is ~15/4000 years, since it’s such a rare event it’s reasonable to
model it as a Poisson process, with a λ of 0.375 (per century). Over the last 4000 years that’s a mean expectation of 0.375/century with a variance of 0.375.
From a Poisson analysis you’d expect ~27 centuries without a melt, ~10 centuries with one melt year, ~2 centuries which is in reasonable agreement with the data.
I find the timing interesting. It occured downwind of the United States East Coast just at the end of their heatwave. Consider the possibility that the jetstream steered all that hot air northeast. It’s also a warm year in the Arctic, from the ice extent and snow cover data, which would make a transient melting event like this more likely.
http://nsidc.org/arcticseaicenews/2012/07/