We constantly hear that the warmest years on record have all occurred in the most recent decades, and of course, we are led to believe this must be a result of the ongoing buildup of greenhouse gases. In most places, we have approximately 100 years of reliable temperature records, and we wonder if the warmth of the most recent decades is unusual, part of some cyclical behavior of the climate system, or a warm-up on the heels of a cold period at the beginning of the record. A recent article in Geophysical Research Letters has an intriguing title suggesting a 2,000 year temperature record now exists for China - we definitely wanted to see these results of this one.

The article was authored by six scientists with the Chinese Academy of Sciences in Beijing, the State University of New York at Albany, and Germany’s Justus-Liebig University in Giessen; the research was funded by the Chinese Academy of Sciences, National Natural Science Foundation of China, and the United States Department of Energy. In their abstract, Ge et al. tell us “The analysis also indicates that the warming during the 10-14th centuries in some regions might be comparable in magnitude to the warming of the last few decades of the 20th century.” From the outset, we knew we would welcome the results from any long-term reconstruction of regional temperatures.

The authors begin noting that “The knowledge of past climate can improve our understanding of natural climate variability and also help address the question of whether modern climate change is unprecedented in a long-term context.” We agree! Ge et al. explain that “Over the recent past, regional proxy temperature series with lengths of 500-2000 years from China have been reconstructed using tree rings with 1-3 year temporal resolution, annually resolved stalagmites, decadally resolved ice-core information, historical documents with temporal resolution of 10-30 years, and lake sediments resolving decadal to century time scales.” However, the authors caution “these published proxy-based reconstructions are subject to uncertainties mainly due to dating, proxy interpretation to climatic parameters, spatial representation, calibration of proxy data during the reconstruction procedure, and available sample numbers.”

Ge et al. used a series of multivariate statistical techniques to combine information from the various proxy methods, and the results included the reconstruction of regional temperatures and an estimate of uncertainty for any given year. They also analyzed temperature records from throughout China over the 1961 to 2007 period and established five major climate divisions in the country (Figure 1 -enlarged here).

Figure 1. Types, lengths, and locations of proxy temperature series and observation used in the Ge et al. study. The five climate regions were based on a “factor analysis” of the 1961-2007 instrumental measurements. Grey shading indicates elevation (from Ge et al., 2010).

The bottom line for this one can be found in our Figure 2 that shows the centennially-smoothed temperature reconstruction for the five regions of China. With respect to the Northeast, Ge et al. comment “During the last 500 years, apparent climate fluctuations were experienced, including two cold phases from the 1470s to the 1710s and the 1790s to the 1860s, two warm phases from the 1720s to the 1780s, and after the 1870s. The temperature variations prior to the 1500s show two anomalous warm peaks, around 300 and between approximately 1100 and 1200, that exceed the warm level of the last decades of the 20th century.” The plot for the Northeast shows warming in the 20th century, but it appears largely to be somewhat of a recovery from an unusually cold period from 1800 to 1870. Furthermore, the plot shows that the recent warming is less than warming that has occurred in the past.

Figure 2 (enlarged here). Five regionally coherent temperature reconstructions with 100-year resolution; the dashed line is the part with fewer series used; and the solid line is the mean value. The shaded areas are the two coldest periods, during the 1620s-1710s and 1800s-1860s (from Ge et al., 2010).

The Central East region also has a 2,000 year reconstruction and Ge et al. state “The 500-year regional coherent temperature series shows temperature amplitude between the coldest and warmest decade of 1.8C. Three extended warm periods were prevalent in 1470s-1610s, 1700s-1780s, and after 1900s. It is evident that the late 20th century warming stands out during the past 500 years. Considering the past 2000 years, the winter half-year temperature series indicate that the three warm peaks (690s-710s, 1080s-1100s and 1230s-1250s), have comparable high temperatures to the last decades of the 20th century.” No kidding - the plot for the Central East region shows that the warmth of the late 20th century was exceeded several times in the past.

Commenting on the Tibet reconstruction, Ge et al. state “The warming period of twenty decadal time steps between the 600s and 800s is comparable to the late 20th century.” In the Northwest, they note “Comparable warm conditions in the late of 20th century are also found around the decade 1100s.” Unfortunately, no long-term reconstruction was possible for the Southeast region.

In summarizing their work, Ge et al. report :

From Figure 3 [our Figure 2 -eds.] , the warming level in the last decades of the 20th century is unprecedented compared with the recent 500 years. However, comparing with the temperature variation over the past 2000 years, the warming during the last decades of the 20th century is only apparent in the TB region, where no other comparable warming peak occurred. For the regions of NE and CE, the warming peaks during 900s-1300s are higher than that of the late 20th century, though connected with relatively large uncertainties.

We get the message - the recent warming in at least several regions in China has likely been exceeded in the past millennium or two, the rate of recent warming was not unusual, and the observed warming of the 20th century comes after an exceptionally cold period in the 1800s.

Declaring that anthropogenic greenhouse gas emissions have pushed modern temperature beyond their historical counterparts disregards the lessons of 2,000 years of Chinese temperatures.

Reference: Ge, Q.-S., J.Y. Zheng, Z.-X. Hao, X.-M. Shao, W.-C. Wang, and J. Luterbacher. 2010. Temperature variation through 2000 years in China: An uncertainty analysis of reconstruction and regional difference. Geophysical Research Letters, 37, L03703, doi:10.1029/2009GL041281.

See posthere.

Retired school principal Kenskingdom was alarmed by this Bureau of Meterology graph, showing a strong warming trend for Victoria (enlargeed here):

He checked the data from which the trend, and found it had first been adjusted and turned into “high quality” data. As a BOM spokesman assured him:

On the issue of adjustments you find that these have a near zero impact on the all Australian temperature because these tend to be equally positive and negative across the network (as would be expected given they are adjustments for random station changes).

Actually, no, though. You see, Kenskingdom discovered that the adjustments served to exaggerate Victoria’s warming remarkably (enlarged here)

Kenskingdom goes through the individual stations for you and concludes:

There is a distinct warming trend in Victoria since the 1960s, which has been especially marked in the last 15 years.

The first half of the record shows a cooling trend.  BOM’s adjustments have attempted to remove this.

2007, not 2009, was the warmest year in the past 100 years.

Three stations identified as urban in 1996 have been included.

Many stations’ data have been arbitrarily adjusted to cool earlier years

Only one station has had its trend reduced.  Two are essentially unchanged.

Ten of Victoria’s 13 stations have been adjusted to increase the warming trend, to the extent that there is a warming bias of at least 133%, more likely 143%.

These adjustments, and the Australian temperature record to which they contribute, are plainly not to be trusted. 

UPDATE

More climate wisdom from the Bureau of Metereology:

Melbourne has experienced its wettest June in nine years, recording 59 millimetres of rain, 10 millimetres more than the long term average…

But despite the damper conditions, the Bureau of Meteorology says there’s no end in sight to the drought.

The heavy June rain was, once again, not quite what the warmist BOM predicted back in March:

Contrasting this, the chances are between 30 and 40% for above average June quarter falls in an area encompassing much of central to southeastern SA, northwest Victoria and the far southwest corner of NSW.  Across the rest (and most) of the country, the chances of exceeding the median April to June rainfall are between 40 and 60%, meaning that above average falls are about as equally likely as below average falls.

UPDATE 2

Weather is not climate, which is worth remembering when you hear the next screams of “global warming” on a hot day:

Sydney’s week of cold weather continues, with the city recording its coldest June morning since 1949 when temperatures dived to 4.3 degrees. (Thanks to reader Professor Frank.)

See Andrew’s blog post here.

Energy Policy: Our interior secretary plans to reinstate the offshore drilling moratorium struck down by a federal judge. But if deep-water drilling is so unsafe, why are we helping Brazil drill nearly three times as deep?

Maybe Secretary Ken Salazar can explain why Britain and others can safely drill in the North Sea and no other nation has suspended its offshore drilling. Yet there he was Tuesday saying he’ll reissue a reworded moratorium that will make it clear to dunces like U.S. District Judge Martin Feldman why offshore drilling is unsafe.

As with health care reform and other issues, the administration’s position is that we didn’t make it clear enough, so we will speak slower and use smaller words. But double talk is double talk no matter how you rearrange the words.

“The decision to impose a moratorium on deep-water drilling was and is the right decision,” Salazar said, even after he was caught rewording a report so a team of experts he assembled would look like they supported the moratorium, when in fact, they adamantly opposed it and thought it would do more harm than the Deepwater Horizon spill itself.

“If some drilling equipment parts are flawed, is it rational to say all are?” Feldman asked in his ruling. “Are all airplanes a danger because one was? All oil tankers like Exxon Valdez? All trains? All mines?

“That sort of thinking seems heavy-handed, and rather overbearing.” Not for an administration and its environmentalist supporters whose collective goal is not to drill safely, but to drill not at all, at least not here.

Last August, the U.S. Export-Import Bank issued a “preliminary commitment” letter to Brazil’s state-run Petrobras in the amount of $2 billion, with the promise of more to follow. Why are we lending billions to a foreign oil company that made $15 billion last year?

These taxpayer dollars finance exploration of the huge offshore discovery in Brazil’s Tupi oil field in the Santos Basin near Rio de Janeiro. Apparently there are no pristine beaches full of tourists there. Someday we may be importing that oil we’re helping Brazil get at.

Has that letter been rescinded as part of the moratorium? Why are Brazil’s offshore fields safe but ours aren’t?

The irony is that most of the deep-water rigs idled by the moratorium may shortly be snapped up by a Petrobras apparently undeterred by images of tar balls on Rio’s beaches. Petrobras plans to drill to a depth of 14,022 feet, a depth that makes our 500-foot limit laughable. Brazil is going big-game hunting, and we’re stuck in the petting zoo.

A recent study by Science Applications International Corp. shows that failure to exploit our domestic and offshore resources translates into some $2.3 trillion in lost opportunity costs for the U.S. economy over the next two decades. The American Petroleum Institute estimates that exploiting these resources would generate nearly 160,000 well-paying jobs and $1.7 trillion in federal, state and local revenues, with $1.3 trillion from offshore drilling alone.

If the moratorium stands and energy prices rise, the only ones to profit will be foreign-owned companies such as Petrobras and investors such as George Soros, who has an investment in the oil giant in the neighborhood of $900 million. Yes, the same George Soros who also is a major investor in the Democratic Party and President Obama’s 2008 campaign.

Soros would love to see domestic offshore drilling shut down and those three dozen deep-water rigs sitting idle shipped off to the coast of Brazil. He has a huge investment in both Petrobras and the Democrats. He expects a return on all his investments.

While we track the trail of oil gushing from Deepwater Horizon, we should also follow the money that will be gushing into George Soros’ bank account, courtesy of the U.S. government and the American taxpayer. Read post here.

A global shift in winds is what led to the end of Earth’s last ice age - an event that ushered in a warmer climate and the birth of human civilization.

It is believed that, in the geological blink of an eye, ice sheets in the northern hemisphere began to collapse and warming spread quickly to the south.

Enlarged here.

Most scientists say that the trigger, at least initially, was an orbital shift that caused more sunlight to fall across Earth’s northern half.

But they could not explain how the south dealt with the shift so fast.

And now a team of researchers looked for an answer towards a global shift in winds and proposed a chain of events that began with the melting of the large northern hemisphere ice sheets about 20,000 years ago.

The melting ice sheets reconfigured the planet’s wind belts, pushing warm air and seawater south, and pulling carbon dioxide from the deep ocean into the atmosphere, allowing the planet to heat even further.

Their hypothesis makes use of climate data preserved in cave formations, polar ice cores and deep-sea sediments to describe how Earth finally thawed out.

“This paper pulls together several recent studies to explain how warming triggered in the north moves to the south, ending an ice age,” said study co-author Bob Anderson, a geochemist at Columbia University’s Lamont-Doherty Earth Observatory.

“Finally, we have a clear picture of the global teleconnections in Earth’s climate system that are active across many time scales. These same linkages that brought the earth out of the last ice age are active today, and they will almost certainly play a role in future climate change as well,” he added.

“It’s the great global warming of all time. We’re trying to answer the puzzle: why does the Earth, when it appears so firmly in the grip of an ice age, start to warm?” said the study’s lead author, George Denton, a glaciologist at the University of Maine.

Scientists have long suspected that carbon dioxide played a major role in the last ice age but have had trouble explaining the early warming in the southern hemisphere, where glaciers in Patagonia and New Zealand were melting before carbon dioxide levels rose significantly.

Some scientists suggest that a change in ocean currents, triggered by the freshening of the North Atlantic, caused this early warming.

But computer models using ocean circulation to explain the rapid warming in the south have been unable to recreate the large temperature jumps seen in the paleoclimate record.

Now, with the evidence for shifting southern hemisphere westerlies, the rapid warming is readily explained.

The study has been published in the journal Science. See more here.

Last week the beleaguered global warming lobby was exulting over what it took to be the best news it has had in a long time. A serious allegation, which last January rocked the authority of the UN’s Intergovernmental Panel on Climate Change, was “corrected” as untrue by The Sunday Times, the newspaper which most prominently reported it. The reputation of the IPCC, it seemed, had been triumphantly vindicated. The growing tide of scepticism over climate change had at last been reversed. But this episode leaves many questions unanswered.

The “correction”, gleefully quoted by everyone from the WWF and The New York Times to The Guardian’s George Monbiot related to what was known as “Amazongate”. This was one of the series of controversies which exploded round the IPCC last winter, when it was shown that many of the high-profile claims made in its 2007 report had been based on material produced by environmental activists and campaigning groups rather than on proper, peer-reviewed scientific evidence.

2008 was the year man-made global warming was disprovedOne example, also reported in The Sunday Telegraph, was the IPCC’s much-publicised claim that climate change, leading to a reduction in rainfall, was threatening the survival of “up to 40 per cent” of the Amazon rainforest. The only source the IPCC could cite for this in its report was a document from the environmental advocacy group WWF. But last week The Sunday Times, in its prominent “correction” to its own story, conceded that the IPCC’s claim was “supported by peer-reviewed scientific evidence” after all. Not identified, however, was the nature of this peer-reviewed evidence. Where is it?

The story of “Amazon-gate” has unfolded through three stages. Step one was the passage in the IPCC report almost identical to one made in a non-peer-reviewed WWF paper of 2000 on forest fires in the Amazon. Specifically the IPCC stated that “up to 40 per cent of the Amazonian forests could react drastically to only a slight reduction in precipitation”. But the only source the WWF in turn had been able to cite to support this was a paper published in Nature in 1999, from a team led by Dr Daniel Nepstad, formerly employed by the WWF but now the “senior scientist” with another advocacy group closely linked to the WWF, the Woods Hole Research Center. Certainly Nepstad’s paper was peer-reviewed: however its subject was not climate change but the impact on the Amazon rainforest of “logging and fire”. It found that “logging companies in Amazonia kill or damage 10-40 per cent of the living biomass of forests”. This had nothing whatever to do with global warming but was cited as the origin of that “up to 40 per cent” figure later used by the WWF and the IPCC.

Step two, when all this was reported last January, was a disclaimer from the WWF, emphasising that its 2000 report did “not say that 40 per cent of the Amazon forest is at risk from climate change”. But it went on to say that the real source for its 2000 paper (which had been “mistakenly omitted") was another paper, “Fire in the Amazon”. This was also written by Dr Nepstad, as head of yet another advocacy group linked to Woods Hole, the Amazon Environmental Research Institute. Although it was now being suggested that this paper should have been cited as the original source for the IPCC’s claim, it too was not peer-reviewed. Thus, twice over, the IPCC’s claim appears to rest both on non-peer-reviewed science and on studies not related to global warming at all.

So great was the IPCC’s embarrassment over these revelations that the story moved to a third stage. Various scientists, led by Dr Nepstad, suggested further studies which might justify the claim. But an exhaustive trawl through all the scientific literature on this subject by my colleague Dr Richard North (who was responsible for uncovering “Amazongate” in the first place), has been unable to find a single study which confirms the specific claim made by the IPCC’s 2007 report. If one exists we would very much like to see it.

There are several studies based on computer models which attempt to estimate the possible impact of climate change on the Amazon rainforest, but none of these have so far supported that 40 per cent figure. Other researchers in turn have been highly critical of these models, suggesting that they are too crude to replicate the complex workings of the Amazonian climate system and that all observed evidence indicates that the forest is much more resilient to climate fluctuations than the alarmists would have us believe.

Nothing did more to excite attention over the effect of climate change on the rainforest than the exceptional drought of 2005, just when the IPCC’s 2007 report was being compiled. Since then, however, abnormally heavy rainfall in the region has brought disastrous floods to Brazil, both last year and again last week.

In other words there is a real mystery here. Nothing so far made public seems to justify an assertion that the IPCC’s specific claim is “supported by peer-reviewed scientific evidence”. In view of all the controversy this issue has aroused over several months, it might seem odd that, if such evidence exists, it hasn’t been produced before. Is it not now a matter of considerable public interest that we should be told what it is? See story here.

Another fine piece can be found here.

Research (below, enlarged here) shows the Amazon has benefited from increased CO2 even as deforestation took place (source CO2 Science).

Deforestation of the Amazon has been decreasing (below, enlarged here) .

Though the animal kingdom is being affected (below, enlarged here).

See also Amazongate, the Smoking Gun here.