Posted on 06/22/2006 8:28:41 AM PDT by Semus Dynnen
Study Says Earth's Temp at 400-Year High Jun 22 11:10 AM US/Eastern
By JOHN HEILPRIN Associated Press Writer
WASHINGTON
The Earth is the hottest it has been in at least 400 years, probably even longer. The National Academy of Sciences, reaching that conclusion in a broad review of scientific work requested by Congress, reported Thursday that the "recent warmth is unprecedented for at least the last 400 years and potentially the last several millennia."
A panel of top climate scientists told lawmakers that the Earth is running a fever and that "human activities are responsible for much of the recent warming." Their 155-page report said average global surface temperatures in the Northern Hemisphere rose about 1 degree during the 20th century.
The report was requested in November by the chairman of the House Science Committee, Rep. Sherwood Boehlert, R-N.Y., to address naysayers who question whether global warming is a major threat.
Last year, when the House Energy and Commerce Committee chairman, Rep. Joe Barton, R-Texas, launched an investigation of three climate scientists, Boehlert said Barton should try to learn from scientists, not intimidate them.
The Bush administration also has maintained that the threat is not severe enough to warrant new pollution controls that the White House says would have cost 5 million Americans their jobs.
Climate scientists Michael Mann, Raymond Bradley and Malcolm Hughes had concluded the Northern Hemisphere was the warmest it has been in 2,000 years. Their research was known as the "hockey-stick" graphic because it compared the sharp curve of the hockey blade to the recent uptick in temperatures and the stick's long shaft to centuries of previous climate stability.
The National Academy scientists concluded that the Mann-Bradley-Hughes research from the late 1990s was "likely" to be true, said John "Mike" Wallace, an atmospheric sciences professor at the University of Washington and a panel member. The conclusions from the '90s research "are very close to being right" and are supported by even more recent data, Wallace said.
The panel looked at how other scientists reconstructed the Earth's temperatures going back thousands of years, before there was data from modern scientific instruments.
For all but the most recent 150 years, the academy scientists relied on "proxy" evidence from tree rings, corals, glaciers and ice cores, cave deposits, ocean and lake sediments, boreholes and other sources. They also examined indirect records such as paintings of glaciers in the Alps.
Combining that information gave the panel "a high level of confidence that the last few decades of the 20th century were warmer than any comparable period in the last 400 years," the academy said.
Overall, the panel agreed that the warming in the last few decades of the 20th century was unprecedented over the last 1,000 years, though relatively warm conditions persisted around the year 1000, followed by a "Little Ice Age" from about 1500 to 1850.
The scientists said they had less confidence in the evidence of temperatures before 1600. But they considered it reliable enough to conclude there were sharp spikes in carbon dioxide and methane, the two major "greenhouse" gases blamed for trapping heat in the atmosphere, beginning in the 20th century, after remaining fairly level for 12,000 years.
Between 1 A.D. and 1850, volcanic eruptions and solar fluctuations were the main causes of changes in greenhouse gas levels. But those temperature changes "were much less pronounced than the warming due to greenhouse gas" levels by pollution since the mid-19th century, it said.
The National Academy of Sciences is a private organization chartered by Congress to advise the government of scientific matters.
It is not just a mathematical error. Statisticians McKittrick and McIntyre exposed the ruse. Mann's "hockey stick" is an extreme torturing and distortion of the data. It is so extreme that it can't just be an error--it's intentional. It not only assumes (extrapolates) a flat climate curve during the Medieval Warming Period for bristlecone pine data, it uses multiple iterations to "smooth" out the MWP from the other data and heavily weights the bristlecone pine data to artificially show a sudden curve upward at the beginning of the 20th Century. What is ironic about the bristlecone pine data is that the tree ring growth doesn't match actual temperature readings from the area, which show no warming.
The importance to the global warming hoax is the elimination of the MWP, the Holy Grail of global warming alarmists.
An OBVIOUS conclusion from the relevant data.
Now, what we need to do is for all of us to turn on our air conditioners, all at once, and open our windows so the cool air can get out and re-freeze the ice caps. Then we'll send air conditioner probes to Mars to fix the ice caps there, since they're melting too.......
aarrrrrgh!
Bloody Davey Vane
The Little Ice Age (LIA) was a period of cooling lasting approximately from the 14th to the mid-19th centuries, although there is no generally agreed start or end date: some confine the period to 1550-1850. This cooler period occurs after a warmer era known as the Medieval climate optimum. There were three minima, beginning about 1650, about 1770, and 1850, each separated by slight warming intervals [1].
It was initially believed that the LIA was a global phenomenon; it is now less clear that this is true. See Medieval climate optimum for more on this.
The IPCC, based on Bradley and Jones, 1993; Hughes and Diaz, 1994; Crowley and Lowery, 2000 describes the LIA as a modest cooling of the Northern Hemisphere during this period of less than 1°C, and says current evidence does not support globally synchronous periods of anomalous cold or warmth over this timeframe, and the conventional terms of "Little Ice Age" and "Medieval Warm Period" appear to have limited utility in describing trends in hemispheric or global mean temperature changes in past centuries.
There remains evidence, however, that the Little Ice Age did also affect the Southern Hemisphere, see below.
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There is no agreed beginning year to the Little Ice Age, although there are a frequently referenced series of events preceding the known climatic minima. Starting in the 13th century, pack ice began advancing southwards in the North Atlantic, as well as glaciers in Greenland. The three years of torrential rains beginning in 1315 ushered in an era of unpredictable weather in Northern Europe which did not lift until the 19th century. There is anecdotal evidence of expanding glaciers almost worldwide, but a climate reconstruction based on glacial length [2] shows no great variation from 1600 to 1850, though it shows strong retreat thereafter.
For this reason, scholars tend to use any of several dates ranging over 400 years for the beginning of the Little Ice Age:
In contrast to its vague beginning, there is an almost undisputed consensus that the end of the Little Ice Age was in the mid-19th century.
The Little Ice Age brought bitterly cold winters to many parts of the world, but is most thoroughly documented in Europe and North America. In the mid-17th century, glaciers in the Swiss Alps advanced, gradually engulfing farms and crushing entire villages. The river Thames and the canals and rivers of the Netherlands often froze over during the winter, and people skated and even held frost fairs on the ice. The winter of 1794/95 was particularly harsh when the French invasion army under Pichegru could march on the frozen rivers of the Netherlands, whilst the Dutch fleet was fixed in the ice in Den Helder harbour. In the winter of 1780, New York Harbor froze, allowing people to walk from Manhattan to Staten Island. Sea ice surrounding Iceland extended for miles in every direction, closing that island's harbors to shipping. "The Arctic pack ice extended so far south that there are six records of Inuit landing their kayaks in Scotland, and there are even reports of a Polar Bear harassing crofters in the Orkney Islands [3]." (disputed — see talk page)
The severe winters affected human life in ways large and small. The population of Iceland fell by half, and the Viking colonies in Greenland died out. In North America, American Indians formed leagues in response to food shortages [4].
"In many years, snowfall was much heavier than recorded before or since, and the snow lay on the ground for many months longer than it does today [5]." Many springs and summers were outstandingly cold and wet, although there was great variability between years and groups of years. Crop practices throughout Europe had to be altered to adapt to the shortened, less reliable growing season, and there were many years of death and famine (such as the Great Famine of 1315-1317, although this may have been before the LIA proper). Viticulture entirely disappeared from some northern regions. Violent storms caused massive flooding and loss of life. Some of these resulted in permanent losses of large tracts of land from the Danish, German, and Dutch coasts [6].
The extent of mountain glaciers had been mapped by the late 1800s. In both the north and the south temperate zones of our planet, snowlines (the boundaries separating zones of net accumulation from those of net ablation) were about 100 m lower than they were in 1975 [7]. In Glacier National Park, the last episode of glacier advance came in the late 18th and early 19th century [8]. In Chesapeake Bay, Maryland, large temperature excursions during the Little Ice Age (~1400-1900 AD) and the Medieval Warm Period (~800-1300 AD) possibly related to changes in the strength of North Atlantic thermohaline circulation [9].
In Ethiopia and Mauritania, permanent snow was reported on mountain peaks at levels where it does not occur today. Timbuktu, an important city on the trans-Saharan caravan route, was flooded at least 13 times by the Niger River; there are no records of similar flooding before or since. In China, warm weather crops, such as oranges, were abandoned in Jiangxi Province, where they had been grown for centuries. In North America, the early European settlers also reported exceptionally severe winters. For example, in 1607-8 ice persisted on Lake Superior until June [10].
The Little Ice Age can be seen in the art of the time; for example, snow dominates many village-scapes by the Flemish painter Pieter Brueghel the Younger, who lived from 1564 to 1638.
Another famous person to live during the LIA was Antonio Stradivari, a violin maker. The colder climates of the time caused the wood from the trees he used to be denser; the superb tone of Stradivari's creations has been partially attributed to this. However, critics of this theory point out that many violin makers who used the same wood that Stradivari used failed to attain similar perfections of tone in their instruments, and that the violins Stradivari made from broad-ringed wood are tonally equal to his dense-wood creations.
Burroughs (Weather, 1981) analyses the depiction of winter in paintings. He notes that this occurred almost entirely from 1565 to 1665, and was associated with the climatic decline from 1550 onwards. He notes that before this there were almost no depictions of winter in art, and hypothesises that the unusually harsh winter of 1565 inspired great artists to depict highly original images, and the decline in such paintings was a combination of the "theme" having been fully explored, and mild winters interrupting the flow of painting.
The famous winter paintings by Pieter Brueghel the Elder (e.g. Hunters in the Snow) all appear to have been painted in 1565. Burroughs states that Pieter Brueghel the Younger "slavishly copied his father's designs. The derivative nature of so much of this work makes it difficult to draw any definite conclusions about the influence of the winters between 1570 and 1600...". Dutch painting of the theme appears to begin with Avercamp after the winter of 1608. There is then an interruption of the theme between 1627 and 1640, with a sudden return thereafter; this hints at a milder interlude in the 1630s. The 1640s to the 1660s cover the major period of Dutch winter painting, which fit with the known proportion of cold winters then.
The final decline in winter painting, around 1660, does not coincide with an amelioration of the climate; Burroughs therefore cautions against trying to read too much into artistic output, since fashion plays a part. He notes that winter painting recurs around the 1780s and 1810s, which again marked a colder period.
By far, one of the most famous American paintings is that of George Washington's crossing of the Delaware River during the winter of 1776-1777. While many heroic depictions like these have been cited as overly zealous, this famous painting by Emanuel Leutze is remarkably accurate to the environment, crossing an icepack. Today the Delaware River, being located at the 38th to 42nd parallel north, rarely freezes.
An ocean sediment core from the eastern Bransfield Basin, Antarctic Peninsula shows centennial events that the authors link to the Little Ice Age and Medieval Warm Period [11], although "Other unexplained climatic events comparable in duration and amplitude to the LIA and MWP events also appear."
The LIA is hard to distinguish in the Quelccaya Ice Cap (Peruvian Andes, South America) [12]
The Siple Dome (SD) has a climate event with an onset time that is coincident with that of the LIA in the North Atlantic based on a correlation with the GISP2 record. This event is the most dramatic climate event seen in the SD Holocene glaciochemical record [13]. The Siple Dome ice core also contained its highest rate of melt layers (up to 8%) between 1550 and 1700, most likely due to warm summers during the LIA. [14]
Law Dome ice cores show lower levels of CO2 mixing ratios during 1550-1800 A.D., probably as a result of colder global climate [15].
Sediment cores (Gebra-1 and Gebra-2) in Bransfield Basin, Antarctic Peninsula, have neoglacial indicators by diatom and sea-ice taxa variations during the period of the LIA [16].
In 1836, snow fell in the city centre of Sydney, Australia, the only time since European settlement in 1788 that this has occurred.
Tropical Pacific coral records indicate the most frequent, intense ENSO activity occurred in the mid-17th century, during the Little Ice Age [17].
In the North Atlantic, sediments accumulated since the end of the last ice age nearly 12,000 years ago show regular increases in the amount of coarse sediment grains deposited from icebergs melting in the now open ocean, indicating a series of 1-2ºC (2-4°F) cooling events recurring every 1,500 years or so. The most recent of these cooling events was the Little Ice Age. These same cooling events are detected in sediments accumulating off Africa, but the cooling events appear to be larger, ranging between 3-8ºC (6-14°F) [18].
Scientists have identified two causes of the Little Ice Age from outside the ocean/atmosphere/land systems: decreased solar activity and increased volcanic activity. Research is ongoing on more ambiguous influences such as internal variability of the climate system, and anthropogenic influence (Ruddiman). Ruddiman has speculated that depopulation of Europe during the Black Death, with the resulting decrease in agricultural output and reforestation taking up more carbon from the atmosphere, may have prolonged the Little Ice Age [19].
One of the difficulties in identifying the causes of the Little Ice Age is the lack of consensus on what constitutes "normal" climate. While some scholars regard the LIA as an unusual period caused by a combination of global and regional changes, other scientists see glaciation as the norm for the Earth and the Medieval Warm Period (as well as the Holocene interglacial period) as the anomalies requiring explanation (Fagan).
During the period 1645–1715, right in the middle of the Little Ice Age, solar activity as seen in sunspots was extremely low, with some years having no sunspots at all. This period of low sunspot activity is known as the Maunder Minimum. The precise link between low sunspot activity and cooling temperatures has not been established, but the coincidence of the Maunder Minimum with the deepest trough of the Little Ice Age is suggestive of such a connection [20]. The Sporer Minimum has also been identified with a significant cooling period during the Little Ice Age. Other indicators of low solar activity during this period are levels of carbon-14 and beryllium-10 [21]. The low solar activity is also well documented in astronomical records. Astronomers in both Europe and Asia documented a decrease in the number of visible solar spots during this time period.
Throughout the Little Ice Age, the world also experienced heightened volcanic activity. When a volcano erupts, its ash reaches high into the atmosphere and can spread to cover the whole earth. This ash cloud blocks out some of the incoming solar radiation, leading to worldwide cooling that can last up to two years after an eruption. Also emitted by eruptions is sulfur in the form of SO2 gas. When this gas reaches the stratosphere, it turns into sulfuric acid particles, which reflect the sun's rays, further reducing the amount of radiation reaching the earth's surface. The 1815 eruption of Tambora in Indonesia blanketed the atmosphere with ash; the following year, 1816, came to be known as the Year Without A Summer, when frost and snow were reported in June and July in both New England and Northern Europe.
Beginning around 1850, the world's climate began warming again and the Little Ice Age may be said to have come to an end at that time. Some global warming skeptics believe that the Earth's climate is still recovering from the Little Ice Age and that human activity has nothing to do with present temperature trends. There is a wide consensus among climate scientists, however, that the present sharp upturn in temperatures is primarily caused by the increased proportion of CO2 in the atmosphere caused by human activity.
Scientists, even the untenured con-men pretending to be scientists, agree that we experienced a warming period around the earth about 1,200 years ago.
This is about the time Vikings employed themselves as plunderers, stealing treasure, kidnapping maidens and burning villages.
Since nobody knows what caused the earth to warm, we are left to speculate. And because everyone and their grandmother speculates on global warming, we can, too.
The reason the earth warmed is because the Vikings burned so many villages. The burning villages heated the clouds which caused rain to fall instead of snow, and soon the Vikings were growing grapes in Greenland.
With the warm weather, the Vikings found they could employ their slaves to grow grapes and other food. This left time for the Vikings to pursue other activities like counting their loot. Laying about while overseeing slaves, counting loot and ogling maidens was certainly a less dangerous line of work and more pleasurable.
The Vikings pursued this occupation for about 200 years. And since they weren’t burning villages anymore, the clouds didn’t heat up. So the earth stopped warming, the snow returned, the Earth got hit with a 300 year mini-ice age and the marauding Vikings sailed off into history.
{crickets}...
"The National Academy of Sciences is a private organization chartered by Congress to advise the government of scientific matters."
It is a shame that the National Academy of Sciences has allowed its reputation to be sullied by releasing a report with unsubstantiated assertions. This insistence that global warming is caused by humankind activity is nothing more than a new version of the "Chicken Little" story. Chicken Little concluded that the sky is falling because he got a bump on his head from something falling from the "sky." These academicians are saying that global warming is caused by humankind, instead of asking a few more questions about our natural climate change and variation. It is a shame to see questionable assumptions being recycled so boldly.
2006 - 400 - 1606. So, it's warmer now than in the middle of the little ice age. That's shocking.
For all but the most recent 150 years, the academy scientists relied on "proxy" evidence from tree rings, corals, glaciers and ice cores, cave deposits, ocean and lake sediments, boreholes and other sources. They also examined indirect records such as paintings of glaciers in the Alps.
Is this from scrappleface?
Doesn't this mean it was just as hot 400 years ago, before there were SUV's and Fossil Fuel burning?
The Earth's cliamte has proven to be extremely dynamic and not static. So what is it that we are trying to achieve. To maintain the staus quo. That's not natural either. Are we expected to have no effect on the planet whatsoever. All this panic based on so little knowledge. I'm not arguing a cleaner environment is not preferable - anuyone remember LA in the 70's - but it's the sky is falling attitude that is so ridiculous. What would these people be saying if the world started cooling based on something we did.
The Earth will heat up or it will cool down. History has proven that. This brings me back to my main point - what are they trying to achieve.
fairly level for 12,000 years - excuse me, they don't have much confidence going back 400 years but still show number from 12,000 back; who took the measurments?
The data upon which Kyoto is based (Mann, Bradley, Hughes: Global-Scale Temperature Patterns and Climate Forcing Over the Past Six Centuries, Nature, No. 392, pp. 779-787, 1998) has been documented to be fraudulent by a recent paper published in the British journal "Energy & Environment" and available on the Internet at http://www.multi-science.co.uk/mcintyre_02.pdf
In their paper, titled "CORRECTIONS TO THE MANN et. al. (1998) PROXY DATA BASE AND NORTHERN HEMISPHERIC AVERAGE TEMPERATURE SERIES," Canadian researchers Stephen McIntyre and Ross McKitrick examined the data set of proxies of past climate used by Mann, Bradley and Hughes for the estimation of temperatures from 1400 to 1980. McIntyre and McKitrick determined that the Mann data "contains collation errors, unjustifiable truncation or extrapolation of source data, obsolete data, geographical location errors, incorrect calculation of principal components and other quality control defects."
Applying the Mann methodology to the corrected data "yielded a Northern Hemisphere temperature index in which the late 20th century is unexceptional compared to the preceding centuries."
The fact that Kyoto is based upon fraudulent data should be troubling to anyone without some hidden agenda.
Male Grizzly and Kodiak Bears should expect a little more flirting from female Polar Bears. There's always a silver lining.
The joke is that yes, the climate cahnges, and it will change in ways that are not helpful to humans, and then it will change back.
Why is the Western Ice Sheet of antarctic thickening? It should be melting.
A redistribution of thermal patterns is happening on =the atmosphere, but that happens cyclicly as varified by historic geological records in some of our oldest living trees. This data is being ignored.
Not to mention all of the methane from his A$$hole.
Someone should get him to change his diet.
The sun's varied activity alone can be used to explain the climate variations of the earth, man and his pollution have little to do with it. This solar activity parallels drilled core samples taken from our most ancient trees, data which does not support these chicken little socialist butterflies, and that data is ignored by them.
We are stuck with our sun, and will just have to be flexible enough to put up with any changes it brings, rather than being inflexible as these scientists would have us be.
How did the earth and its life ever survive the Cretaceous period, when there was no ice on the earth at all and 20 times the amount of CO2 in the atmosphere than we have now?
I'll get concerned when they start farming again in Greenland.
That explains it. I was walking outside the other day without shoes on and I burned my feet.
That was good! But I think the -st endings go only with "thou" and he/she/it takes a -th. Maybe "mayeth not?" I'm not sure...
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