Saturday, January 10, 2009

Diamonds scratch Younger Dryas from Climate catastrophe race

As we have previously shown here the cataclysmic examples of abrupt climate change used by the central committee for the reformation of science have once again been seen to be coincidences of a random nature and not a "sign" of some forthcoming event.

We mentioned this previously

The Younger Dryas occurred as an Ice Age was ending. As the climate began to warm, a huge and sudden rush of fresh meltwater broke out from the Great Lakes and swept out to sea. The water surge was monumental enough that the meltwater lowered the salinity of the ocean, shut down the Atlantic conveyor currents, which disperse the planet's heat, and threw the northern hemisphere back into another thousand years of Ice Age. It raised temperatures near Greenland by a startling 15 degrees C, even as it doubled annual rainfall.

Modern climatologists have savored the Younger Dryas event as massive evidence of what comes when we push the planet's climate too close to a "tipping point." Further human-driven warming, they say, will make such abrupt climate changes more likely, with searing droughts, torrential rainfall, and extreme heat.

The National Academy of Sciences issued a 2002 report titled Abrupt Climate Change: Inevitable Surprises, which said abrupt climate changes have been especially common when the climate system was being forced to change most rapidly. According to that theory, greenhouse warming today could be drastically increasing risks from climate change.

Arbitary assumptions from the “model makers” and their creationist theories of a “steady state planet”

The NSF have released an interesting article on a ‘Hammer of God” event that provides evidence that the model makers are wrong and an “extraterrestrial event” in the form of a comet was the precursor

In an article in the NYT

Now researchers are reporting that the abrupt cooling — which took place about 12,900 years ago, just as the planet was emerging from an ice age — may have been caused by one or more meteors that slammed into North America.

That could explain the extinction of mammoths, saber-tooth tigers and maybe even the first human inhabitants of the Americas, the scientists report in Friday’s issue of the journal Science.

The hypothesis has been regarded skeptically, but its advocates now report perhaps more convincing residue of impact: a thin layer of microscopic diamonds found in rocks across America and in Europe.

Already the disciples for the doctrine of the infallibility of the order(ipcc) are trying to muddy the waters but hte isotopes already sing the ship (and it is not rising sea levels)

A dramatic increase about 12,000 years ago in levels of atmospheric methane, a potent greenhouse gas, was most likely caused by higher emissions from tropical wetlands or from plant production, rather than a release from seafloor methane deposits, a new study concludes.

This research, to be published Friday in the journal Science, contradicts some suggestions that the sudden release of massive amounts of methane frozen in seafloor deposits may have been responsible – or at least added to - some past periods of rapid global warming, including one at the end of the last ice age.

The findings were made with analysis of carbon isotopes from methane frozen in Greenland ice core samples, by researchers from Oregon State University, the University of Victoria, University of Colorado, and the Scripps Institution of Oceanography at the University of California-San Diego.

For climate researchers, an understanding of methane behavior is of some significance because it is the second most important "greenhouse gas" after carbon dioxide. Its atmospheric concentration has increased about 250 percent in the last 250 years, and it continues to rise about 1 percent a year.

"Methane is a gas that makes a significant contribution to global warming but has gone largely unnoticed by the public and some policy makers," said Hinrich Schaefer, a postdoctoral research associate in the OSU Department of Geosciences. "Its concentration has more than doubled since the Industrial Revolution, from things like natural gas exploration, landfills, and agriculture. We need to know whether rapid increases of methane in the past have triggered global warming or just been a reaction to it."

To better answer this question, researchers studied two stable isotopes of carbon found in methane, that can provide a better idea of where the methane came from during a period thousands of years ago when Earth was emerging from its most recent ice age, and entering the interglacial period that it is still in. At that time, methane concentration went up 50 percent in less than 200 years.

Several things naturally produce methane, including biomass burning, geologic sources, wetlands, animals, and aerobic production by plants, a mechanism that was unknown until just recently. And huge amounts of methane – with more carbon stored in them than all the known oil and gas fields on Earth – are found in methane hydrates on the seafloor. In this setting, the cold temperatures and pressure keep the methane stable and prevent it from entering the atmosphere.

But some researchers have theorized that something might release the trapped seafloor methane – submarine landslides, a drop in pressure caused by dropping sea levels, or warming of ocean waters.

As we also no changes in isotopic levels in the biosphere are also present after an extraterrestrial event such as Tunguska are also seen.

The Tunguska catastrophe in 1908 evidently led to high levels of acid rain. This is the conclusion reached by Russian, Italian and German researchers based on the results of analyses of peat profiles taken from the disaster region. In peat samples corresponded to 1908 permafrost boundary they found significantly higher levels of the heavy nitrogen and carbon isotopes 15N and 13C.

The highest accumulation levels were measured in the areas at the epicentre of the explosion and along the trajectory of the cosmic body. Increased concentrations of iridium and nitrogen in the relevant peat layers support the theory that the isotope effects discovered are a consequence of the Tunguska catastrophe and are partly of cosmic origin. It is estimated that around 200,000 tons of nitrogen rained down on the Tunguska region in Siberia at that time.

"Extremely high temperatures occurred as the meteorite entered the atmosphere, during which the oxygen in the atmosphere reacted with nitrogen causing a build up of nitrogen oxides," Natalia Kolesnikova told the Russian news agency RIA Novosti on last Monday. Mrs. Kolesnolova is one of the authors of a study by Lomonosov Moscow State University, the University of Bologna and the Helmholtz Centre for Environmental Research (UFZ), which was published in the journal Icarus in 2003.

The same is also seen in the younger dryas with elevated levels in the biosphere.

Pleistocene faunal δ15N variations are thought to reflect changes in climatic and environmental conditions. Researchers are still unclear, however, which climatic/environmental parameter is the primary control on Pleistocene faunal δ15N values. Through extensive nitrogen isotope analysis of Late Pleistocene reindeer (Rangifer tarandus) collagen we investigated whether permafrost development during the Late Pleistocene coincided with changes in δ15N values. After 45 ka BP reindeer δ15N declined, with lowest δ15N values observed after the Last Glacial Maximum (LGM), between 15 and 11 ka BP. The decline in δ15N appears to be of a greater magnitude in more northern regions than in the South of France, a pattern similar to that previously observed for horse. On a global scale, ecosystem δ15N is controlled by the relative openness of the nitrogen cycle, which in turn is controlled by climate. Low soil and plant δ15N are observed in cold and/or wet regions and high δ15N are seen in hot and/or arid areas. The regional pattern in reindeer δ15N decline mimics the pattern of climatic deterioration in Europe culminating at the LGM, with climate cooling being more intense in northern Europe than in southern Europe. However, the lowest reindeer δ15N values are observed after temperatures started to rise. This may have been due to a lag in the response of the nitrogen cycle to increasing temperatures. Alternatively it may have been linked to the influence of permafrost degradation on soil and plant δ15N and thus faunal δ15N. The renewed climatic cooling during the Younger Dryas did not see a fall in reindeer δ15N. Limited data does, however, suggest a post Younger Dryas depletion in reindeer δ15N values.


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