Bewijzen voor Global Warming stapelen zich op
henk - 27.12.2002 17:20
Global warming en hyperdimensionale fysica
ijsbergen op mars
hyperdimensionale fysica
Non Newtoniaanse objecten
 http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2002/12/23/MN226990.DTL
From the tropics to the poles, evidence is growing stronger than ever that Earth's climate is warming dangerously.
In the Arctic Ocean, floating masses of sea ice are shrinking and splitting apart, and the massive Greenland ice cap melted more this past summer than ever before. Meanwhile, warming ocean temperatures are endangering coral reefs in the tropics.
At the annual fall meeting of the American Geophysical Union in San Francisco earlier this month, a flurry of new reports examining evidence of global climate change all tell the same story.
If the trends continue unchecked, scientists say, rising sea levels will drown coastlines. Droughts in some regions -- and increased rainfall in others -- will alter harvests drastically. And other climate disruptions will destabilize regional ecologies and global economies.
Some of these alarming phenomena may be due to the natural climate variability that the planet has seen over millions of years. But most scientists agree, after years of debate, that humans and their addiction to fossil fuels are at least partly to blame.
"It is humans who are clearly forcing the abrupt climate change we see right now," said Richard B. Alley of Pennsylvania State University, who recently chaired a National Research Council committee looking specifically at climate change.
So-called greenhouse gases trap the sun's radiation much the way glass windows trap heat inside a home or a greenhouse. The most powerful of those gases is carbon dioxide, which comes primarily from burning fossil fuel, while other gases include methane, sulfur dioxide and ozone.
THE BUSH REPORT
A recent NRC report, which the Bush administration requested last year when scientists criticized the White House for its slow response to growing evidence of global warming, concluded that "human-induced warming" will continue through the 21st century.
While it conceded great uncertainties in the many models of climate trends that experts have produced, the report predicted that the planet's climate would warm by 2.5 to 10.4 degrees Fahrenheit by the century's end due to human activity.
Signs of the striking pace of that trend came in reports from many scientists who monitor the ice of the globe's far north.
The Arctic's sea ice -- large masses of snow-covered ice that float everywhere around the polar latitudes -- usually covers 2.4 million square miles of the ocean north of Canada, Greenland and Russia in September, the height of the ice season.
This past summer, however, measurements showed that the sea ice had decreased by nearly a half-million square miles. The flat ice floes left wider sections of open water between them and became extremely thin in many areas, reported Ted Scambos of the National Snow and Ice Data Center in Boulder, Colo.
It marked the most abrupt change in the ocean's ice cover that scientists monitoring the region have seen in 24 years, said Mark Serreze of the data center. Records kept by Icelandic fishermen indicate the cover may not have been so low for centuries.
"I was really surprised by the change," Serreze said. "This was the craziest summer season I've ever seen up there."
MELTING FASTER THAN EVER
Equally ominous was a report by Konrad Steffen, a glaciologist at the University of Colorado, on Greenland's vast ice cover, second only in size to Antarctica. It was melting faster this year across nearly 265,000 square miles than at any period in recorded history, Steffen said.
The ice sheet is a mile and a half thick in some places. As meltwater from the surface seeps through crevices in the ice, it loosens the edges of the sheet and causes the ice to flow more swiftly to the sea, where it breaks off into icebergs.
If the entire Greenland ice sheet were to completely melt -- admittedly an unlikely event, at least in the near future -- then scientists calculate that sea levels would rise by a globally disastrous 23 feet.
Steffen had a firsthand experience of the dangers of melting ice. He and his colleagues were camped on the normally hard-frozen Greenland ice last June when their camp and equipment were flooded under a foot of meltwater and they had to be rescued by helicopter.
The high Arctic is by no means the only part of the world where climate change is becoming more dramatic. Scientists are equally concerned about the impact of changes on tropical oceans.
KILLING CORAL
Coral reefs are living creatures. As they die, their calcite skeletons build up the reefs over millions of years. They are a crucial part of the world's marine ecosystems, vital to the productivity of many tropical fisheries.
Most reefs are in shallow waters near continental and island coasts, where human-caused destruction is widespread from coastal pollution, from tourists trampling the reef organisms, from fishermen ravaging them, and from the hulls of ships grinding over them.
But five years ago, the corals in many parts of the world were afflicted by a mysterious episode of bleaching that slowed their growth and in many regions killed them outright. Researchers note that the bleaching has coincided with increasing ocean temperatures.
"There is growing agreement that doubling of the carbon dioxide in the atmosphere means a 15 percent decline in the coral population," said Robert W. Buddemeier, a senior chemist with the Kansas Geological Survey, who has studied the impact of climate change on coral reefs.
"By the end of the century, with the effects of increasing levels of carbon dioxide on temperature and on ocean chemistry, the corals will be in the worst shape we've seen in the past 50 million years. Things are really dicey," he added.
NO TOUGH MEASURES
The growing evidence of damage from climate change has goaded the Bush administration to push its own research program, although the president does not support any tough measures to control greenhouse gas emissions, including the Kyoto Protocol agreed to by most industrialized nations.
Earlier this month, Assistant Secretary of Commerce James Mahoney, an atmospheric physicist who is Bush's point man on global warming, staged a "workshop" in Washington where 1,500 people from industry, government, academic and environmental organizations worked on plans for a "strategy for climate change research."
"There are still any number of science questions to be resolved," Mahoney told reporters at the AGU meeting in San Francisco. He conceded, however, that already "we will most likely need profound changes in greenhouse gas emissions. "
But to many analysts, time is wasting. Global warming will cause "major political instabilities in the developing world that could disrupt the global economy," said Lester R. Brown, founder of the Earth Policy Institute and a noted environmental analyst who spent 10 years as a policy adviser in the Department of Agriculture.
FOOD SUPPLY IMPACT
If measures aren't taken soon to curb greenhouse gas emissions, the changes in climate will force rapid changes in the way the world's food crops are grown. That has important implications for feeding the world's growing population, expected to increase to at least 9 billion by 2050.
"The vast corn belt of the Northern Hemisphere, for example, will become hotter and dryer, and that change can't be resolved merely by creating new corn belts further north, because the soils further north are not the same at all," Brown said.
"Each global increase of 1 degree Celsius (1.8 degrees Fahrenheit) around the world will reduce grain yields like rice and wheat, as well as corn, by at least 10 percent," he said.
And because aquifers are being tapped at an increasing pace throughout the world and water tables are falling, the outcome will soon mean a devastating blow to agriculture -- particularly in the developing world, he said.
"This disruption by a combination of climate change and water shortages has the potential for creating political instabilities on a scale that we can't even foresee," Brown declared.
E-mail David Perlman at  dperlman@sfchronicle.com.
The Greenland Weather Report
In Greenland, annual ice layers are stacked up like thousands of annual weather reports. In 1982, a European and American team made the first attempt to read that record, by recovering an ice core from southern Greenland. Measurements on the ice core indicated that about 11,700 years ago the climate of the North Atlantic region changed from a dry and cold ice age to the current warmer and wetter Holo cene. Altogether it took 1,500 years for the climate transition to be complete and a few thousand more years to melt most of the ice, but the surprise was that most of the transition occurred in only 40 years. This was only one record, and it came from a single 10-centimeter-diameter ice core. Still, this finding was impossible to ignore and too puzzling to comprehend.
In 1993, Americans and Europeans led by Paul Mayewski of the University of New Hampshire and Bernhard Stauffer of the University of Bern in Switzerland finished recovering two new ice cores from the summit of the Greenland ice sheet. More than 40 university and national laboratories participated in the projects. We shared samples, spent time in one another’s labs, replicated one another’s results, proposed ideas, tore them apart and then jointly proposed better ones. One of the justifications for these new cores, located 30 kilometers apart, was to verify and learn more about the 40-year change in climate, an event observed in both cores. The records stored in these cores were more detailed than before and showed that within a 20-year period at the summit of Greenland, where ice is thickest, the amount of snow deposited each year doubled, average annual surface temperature increased by 5 to 10 degrees Celsius and wind speeds increased. The same ice cores also showed that the spatial extent of sea ice decreased, atmospheric-circulation patterns changed, and the size of the world’s wetlands increased. Many of these shifts in parameters, including at least a 4-degree Celsius increase in the average annual air temperature, happened in less than 10 years. These changes were not restricted to Greenland; the global nature of many of these ice-core records showed that low-latitude, continental-scale regions rapidly got warmer and wetter. The most dramatic change occurred 11,700 years ago. But we also found comparable anomalies every several thousand years during the Wisconsin ice age (see Figure 6). Further, Antarctic ice cores also show comparable climate transitions at these times.
Climate, from the Bottom Down
One can also learn a lot about what controls climate by studying sediments on the ocean floor. These sediments contain the decayed remains of ocean organisms and inorganic material from the erosion of rocks. Ocean organisms assimilate chemical compounds from the water as they grow, and the compounds they incorporate are partially determined by the environment in which they live. Thus the decayed remains of the organisms that fall to the ocean floor contain a record of what chemical compounds were available and the temperature of the water in which they lived.
For example, consider an ocean-sediment core collected at Bermuda Rise, a place where ocean currents deposit a lot of sediment. The oxygen-18/oxygen-16 ratio of seawater varies through time depending on how much water is locked in ice sheets and how much water is in the ocean (see Figure 7). The near surface–dwelling foraminiferan Globigerinoides ruber uses seawater to make its shell. By measuring the oxygen isotopic composition of the shells recovered from an ocean core, we can determine how much water was locked up in ice sheets when the foraminiferan was living. Likewise, the bottom-dwelling foraminiferan Nutallides umbonifera incorporates cadmium and calcium in its shell. By measuring the ratio of cadmium to calcium in the shells recovered from an ocean core, we can tell where the bottom water came from when the foraminiferan was living. High values of the cadmium-to-calcium ratio indicate that the water near the bottom came to the Bermuda Rise from the south, whereas a low ratio indicates that the bottom water came from the north.
Ocean sediments also contain ground-up rock, which is transported and deposited by ocean currents, just as wind carries airborne dust to be deposited on ice sheets. The mineralogy of the ground-up rock can be used to identify where it came from. For example, a layer of hematite-rich sediments in ocean cores near Bermuda indicates that ocean currents were transporting material from the east coast of Canada to Bermuda when the sediments in the layer were deposited.
To determine what the temperature of the ocean surface was in the past we can use organic compounds made by phytoplankton. Phytoplankton live near the ocean surface where there is light for photosynthesis. Some phytoplankton produce compounds know as alkenones which are straight chains of carbon atoms. Along these chains of carbon there can be two or three double bonds. The number of double bonds depends on the water temperature. The double bonds are thought to keep the cell membrane pliable in cold water. When the phytoplankton die, the alkenones fall to the bottom and become incorporated into the sediment. By measuring the ratio of different types of alkenones we can determine what the surface water temperature was when the phytoplankton were living.
By collecting cores of the ocean sediments at different locations, we can determine a lot about how the ocean circulated water and heat in the past. The rapid climate changes recorded in the ice cores encouraged a search for ocean sediment records with high time resolution. In the past few years locations have been identified in the ocean where sediment accumulates rapidly, and the sediment cores from these locations have comparable time resolution to the ice cores. Coring projects off the coast of Bermuda by Konrad Hughen, Julian Sachs and Scott Lehman with the University of Colorado, in conjunction with Lloyd Keigwin of Woods Hole Oceanographic Institution and Ed Boyle of the Massachusetts Institute of Technology, found the same rapid changes in climate as were recorded in the ice cores. Other groups have found similar records near Santa Barbara, California and off the coast of India.
Paleoclimatic evidence worldwide shows that a global change in climate took place 11,700 years ago, and in the North Atlantic a large part of the change took less than 20 years. It was a few thousand years before the completion of the transition from ice age to warm period; still, in just a 20-year period the climate of a large part of the earth changed significantly. There was no warning. A threshold was crossed, and the climate in much of the world shifted abruptly from cold to warm. This was not a small perturbation; our civilization has never experienced a climate change of this magnitude or speed. To get an idea of what happened, imagine that over a 20-year period the weather at your home became that typical of a place 400 to 600 miles farther south. What might be the mechanism for so rapid and large a climate change?
Climate’s Control Mechanism
Like the atmosphere, the oceans are far from static. Currents, of which the Caribbean-Atlantic Gulf Stream is just a small part, continually exchange water among all the oceans and between the surface and the depths. For the sake of convenience, we shall start this journey in the Gulf Stream, where water moves northward along the East Coast of the U.S. toward Iceland. Along the way, the water exchanges heat with the air, warming the air and cooling the water in the process. Water evaporates from the surface and leaves behind dissolved salt. The combination of chilling and evaporation makes surface water denser as it moves north. In the vicinity of Iceland, the surface water becomes denser than the water below it and sinks. This dense, cold water then moves south along the bottom of the Atlantic, around the Horn of Africa and, still near the bottom, continues to the North Pacific, where it upwells to the surface. Surface water in the North Pacific makes room for the upwelling bottom water by moving south, passing between Asia and Australia and finally catching the tail of the circulation pattern at the beginning of the Gulf Stream in the Atlantic off Central America (see Figure 8). For most of its journey, the surface water collects heat and freshwater, which makes the surface water more buoyant than the water underneath it. But in the North Atlantic, the combination of cold temperatures and evaporation makes the water dense again and it sinks.
Wally Broecker of Columbia University likens this circulation pattern to a long conveyor belt that moves water, salt and heat. He was among the first to recognize that alterations in the path of the ocean conveyor belt would change climate in much the same way that turning off the furnace fan changes the temperature distribution in a house. He proposed that the large oscillations in climate observed in the geologic record were caused by different patterns of ocean circulation.
http://www.sigmaxi.org/amsci/articles/99articles/taylorgreen.html
http://www.mars-ice.org/
Confirmation that Maxwell's "hyper-dimensional" inquiries extended far beyond "mere" physical interactions can be seen from another of his "unknown" poems ...
"My soul is an entangled knot,
Upon a liquid vortex wrought
By Intellect in the Unseen residing.
And thine doth like a convict sit,
With marlinspike untwisting it,
Only to find its knottiness abiding;
Since all the tool for its untying
In four-dimensional space are lying."
For, in honor of another great mathematician of the time, multi-dimensional geometer Arthur Cayley, Maxwell wrote ...
"Oh WRETCHED race of men, to space confined!
What honour can ye pay to him, whose mind
To that which lies beyond hath penetrated?
The symbols he hath formed shall sound his praise,
And lead him on through unimagined ways
To conquests new, in worlds not yet created.
First, ye Determinants! In ordered row
And massive column ranged, before him go,
To form a phalanx for his safe protection.
Ye powers of the nth roots of - 1!
Around his head in ceaseless* cycles run,
As unembodied spirits of direction.
And you, ye undevelopable scrolls!
Above the host wave your emblazoned rolls,
Ruled for the record of his bright inventions.
Ye cubic surfaces! By threes and nines
Draw round his camp your seven-and-twenty lines-
http://www.enterprisemission.com/hyper1.html
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