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Thursday, October 19, 2006 

The Five Worst Extinctions in Earth's History - Funny that no SUV's were involved

By Lee Siegel
Saturday, March 05, 2005


Science Writer
posted: 04:12 pm ET
07 September 2000

Humans not to blame...

Here are details of the five worst mass extinctions in Earth’s history and their possible causes, according to paleobiologist Doug Erwin of the Smithsonian Institution’s National Museum of Natural History. Erwin said estimates of extinction rates are from the late John J. Sepkoski at the University of Chicago:

Cretaceous-Tertiary extinction, about 65 million years ago, probably caused or aggravated by impact of several-mile-wide asteroid that created the Chicxulub crater now hidden on the Yucatan Peninsula and beneath the Gulf of Mexico. Some argue for other causes, including gradual climate change or flood-like volcanic eruptions of basalt lava from India’s Deccan Traps. The extinction killed 16 percent of marine families, 47 percent of marine genera (the classification above species) and 18 percent of land vertebrate families, including the dinosaurs.

End Triassic extinction, roughly 199 million to 214 million years ago, most likely caused by massive floods of lava erupting from the central Atlantic magmatic province -- an event that triggered the opening of the Atlantic Ocean. The volcanism may have led to deadly global warming. Rocks from the eruptions now are found in the eastern United States, eastern Brazil, North Africa and Spain. The death toll: 22 percent of marine families, 52 percent of marine genera. Vertebrate deaths are unclear.

Permian-Triassic extinction, about 251 million years ago. Many scientists suspect a comet or asteroid impact, although direct evidence has not been found. Others believe the cause was flood volcanism from the Siberian Traps and related loss of oxygen in the seas. Still others believe the impact triggered the volcanism and also may have done so during the Cretaceous-Tertiary extinction. The Permian-Triassic catastrophe was Earth’s worst mass extinction, killing 95 percent of all species, 53 percent of marine families, 84 percent of marine genera and an estimated 70 percent of land species such as plants, insects and vertebrate animals.

Late Devonian extinction, about 364 million years ago, cause unknown. It killed 22 percent of marine families and 57 percent of marine genera. Erwin said little is known about land organisms at the time.

Ordovician-Silurian extinction, about 439 million years ago, caused by a drop in sea levels as glaciers formed, then by rising sea levels as glaciers melted. The toll: 25 percent of marine families and 60 percent of marine genera.


 

Galactic Dust Storm hits Solar System

By Robert Roy Britt
Saturday, March 05, 2005


Senior Science Writer
posted: 06:33 am ET
14 August 2003

Our solar system's natural defenses are down and a vigorous cosmic dust storm is blowing through, according to a new study. The forecast calls for a prolonged and increasing blizzard of small interstellar bits.

While no serious consequences are expected, the extra dust could slightly alter our night sky and might pose an increased risk to spacecraft, which are vulnerable to high-speed impacts from the tiny particles.

The whole scenario is also a vivid reminder that there is no such thing as empty space.

The number of incoming particles recently tripled and the pace is expected to grow over the next decade. Terrestrial weather and climate will not likely be affected, but more shooting stars could grace the night sky, said the study's leader, Markus Landgraf of the European Space Agency (ESA).

The fresh influx is related to a periodic weakening of the Sun's magnetic field.

The discovery was made using data from ESA's Ulysses spacecraft, which orbits the Sun on a noncircular path between Earth and Jupiter and his been monitoring the situation since 1992. The probe detects small particles and, based on direction, mass and speed, figures out which ones came from outside the solar system.

Threefold increase

The number of interstellar dust grains increased from four per day, per meter in 1997 to 12 per day in 2000, Landgraf said. The results were announced earlier this month. He expects the rate to stay constant until 2005, and then increase by another factor of 3 prior to 2013.

The potential effects are not well known, according to Landgraf and his colleagues at the Max-Planck-Institute.

"Generally interstellar dust is not considered a problem, as it does not penetrate typical spacecraft structures," Landgraf explained in an e-mail interview. "However, due to the high impact velocity, sensitive high-voltage instruments can suffer a short circuit after an exceptionally big impact. Also, sensitive optical instruments have to worry about the erosion of polished surfaces."

Most interstellar grains are just one-hundredth the diameter of a human hair. But they move fast, roughly 58,160 mph (26 kilometers per second) relative to the Sun.

Secondary effects

Any notable effects on Earth will likely involve secondary processes. When interstellar dust hits comets and asteroids, it's like shooting a tiny bullet at a rock, and more dust is kicked up, and the follow-on dust tends to be bigger.

More interstellar dust means more dust generated in-house.

"This has a number of potential effects," Landgraf said, cautioning that they haven't been observed yet, however.

One possibility is an increased number of sporadic meteors, those not associated with known showers like the summer Perseids or the November Leonids. Meteors are created when something vaporizes in Earth's atmosphere. Space rocks as big as peas and baseballs crash through now and then, but most shooting stars are made of mere dust.

It's also possible, Landgraf said, that the eerie Zodiacal Light -- a "false dawn" caused by sunlight reflecting off space dust -- will be enhanced.

And in general, more material might rain down to Earth from space every year.

Astronomers armed with huge telescopes will be interested to see if increased secondary dust brightens the Kuiper Belt, a region of frozen rocks and dust beyond Neptune. "With the brighter dust, especially infrared space telescopes will have a harder time to see faint objects behind the dust," Landgraf said.

Among other tasks, infrared telescopes on the ground and in space are used to study dust around other stars.

More to come

The solar system is always plowing through interstellar material. The Sun's giant magnetic field thwarts much of the dust from entering the solar system. But the magnetic field weakens periodically, on a cycle that lasts roughly 22-years. The cycle is related to an 11-year cycle of sunspot activity.

This is the first of the related dust storms that has been seriously monitored by a spacecraft.

Some day, the influx could get worse. The solar system is plowing toward the fringes of a galactic cloud known as the G-cloud.

"The time of the entry into the G-cloud is unknown, but is expected to occur any time in the next 10,000 years," Landgraf said. "There will be a constant increase [in dust rates], because the G-cloud is more dense than the local interstellar cloud that is now surrounding our Sun."

The study will be published in the Journal of Geophysical Research.


 

Global Warming: Is It Real?

By Robert Roy Britt
Saturday, March 05, 2005

Senior Science Writer
posted: 07:15 pm ET
14 January 2000

In an effort to achieve consensus in one of the most contentious debates in modern science, a panel of 11 climate experts from diverse fields released a report Thursday stating that global warming is in fact a real phenomenon, at least near the surface of the planet.

After debating the issue in roundtable fashion for nine months, the panelists reported a very narrow slice of the debate, choosing to skirt the hot topic of whether or not human activity is contributing to global warming.

Still, the ambition of the report is broad, attempting to put to rest the question of whether or not surface temperatures are rising.

Finding consensus

The panel included university researchers, scientists from NASA and National Oceanic and Atmospheric Administration (NOAA), as well as experts in climate modeling, satellite data interpretation and sea-surface temperature analysis.

The group concluded that satellite data, though frequently debated, shows that the lower and middle troposphere -- a region extending from the Earth's surface to about 5 miles up -- has warmed only a little, if at all, in the past two decades.

The Earth's surface temperature, meanwhile, has risen between 0.7 and 1.4 degrees Fahrenheit (0.4 to 0.8 degrees Celsius) in the last century.

Most computerized climate models predict the troposphere should warm along with rising surface temperatures.

Sponsored by the National Research Council, the panel was organized to reach a consensus on this discrepancy and to determine how to interpret existing data, the accuracy of which is frequently questioned, according to panel member Frank Wentz.

No blame laid

While a combination of human activities and natural causes has contributed to rising surface temperatures, the report states, other human and natural forces may actually have cooled the upper atmosphere.

Volcanic eruptions and the prevalence of several strong El Niño events are but two factors that make it impractical to assume that a 20-year temperature rise reflects any long-term trend.

"The differences between the surface and upper-air trends in no way invalidates the conclusion that the Earth's temperature is rising," said John M. Wallace, chair of the panel and professor of atmospheric sciences at the University of Washington in Seattle. "But the rapid increase in the Earth's surface temperature over the past 20 years is not necessarily representative of how the atmosphere is responding to long-term, human-induced changes."

Wallace said world leaders should "develop an improved climate monitoring system to resolve uncertainties in the data and provide policymakers with the best available information."

Global atmospheric temperatures have been monitored by satellite since 1979 with Microwave Sounding Units on the NOAA's TIROS-N series of polar-orbiting weather satellites (see accompanying image).

But existing satellite sensors are designed to measure day-to-day changes in the weather and are ill-suited for long-term climate modeling, Wentz said. "What we're recommending is a whole new generation of satellite sensors."

The study, funded by NOAA and the Aluminum Corporation of America, was released at a meeting of the American Meteorological Society.


 

Global Warming on Pluto - must be from all those SUV's

Global Warming on Pluto Puzzles Scientists
By Robert Roy Britt
Saturday, March 05, 2005
Senior Science Writer
posted: 01:25 pm ET
09 October 2002

[GHG Note: It should not puzzle scientists "worth their weight" at all... the sun has been more active over a considerable period recently. ]

In what is largely a reversal of an August announcement, astronomers today said Pluto is undergoing global warming in its thin atmosphere even as it moves farther from the Sun on its long, odd-shaped orbit.

Pluto's atmospheric pressure has tripled over the past 14 years, indicating a stark temperature rise, the researchers said. The change is likely a seasonal event, much as seasons on Earth change as the hemispheres alter their inclination to the Sun during the planet's annual orbit.

They suspect the average surface temperature increased about 3.5 degrees Fahrenheit, or slightly less than 2 degrees Celsius.

Pluto remains a mysterious world whose secrets are no so easily explained, however. The warming could be fueled by some sort of eruptive activity on the small planet, one astronomer speculated.

Though Pluto was closest to the Sun in 1989, a warming trend 13 years later does not surprise David Tholen, a University of Hawaii astronomer involved in the discovery.

"It takes time for materials to warm up and cool off, which is why the hottest part of the day on Earth is usually around 2 or 3 p.m. rather than local noon," Tholen said. "This warming trend on Pluto could easily last for another 13 years."

Stellar observations

The conclusion is based on data gathered during a chance passage of Pluto in front of a distant star as seen from Earth. Such events, called occultations, are rare, but two of them occurred this summer.

In the occultations, which are like eclipses, astronomers examined starlight as it passed through Pluto's tenuous atmosphere just before the planet blotted out the light.

The first occultation, in July, yielded limited data because of terrestrial cloud cover above key telescopes. Marc Buie, an astronomer at Lowell Observatory, scrambled to observe the event from northern Chile using portable 14-inch (0.35-meter) telescope. Afterward, Buie said he was baffled by what seemed to be global cooling of Pluto's atmosphere punctuated by some surface warming.

Then on Aug. 20, Pluto passed in front of a different star. The latter event provided much better data captured by eight large telescopes and seems to clarify and mostly reverse the earlier findings.

The results were compared to studies from 1988, the last time Pluto was observed eclipsing a star.

James Elliot of MIT led a team of astronomers who coordinated their observations and presented the findings today at the annual meeting of the American Astronomical Society's (AAS) Division for Planetary Sciences in Birmingham, Ala.

Elliot said the Aug. 20 occultation was the first that allowed such a deep probing of the composition, pressure and the always-frigid temperature of Pluto's atmosphere, which ranges from -391 to -274 degrees Fahrenheit (-235 to -170 degrees Celsius).

Volcanoes on Pluto?

Elliot hinted at the possibility of another factor fueling Pluto's warming trend.

He compared Pluto to Triton, a moon of Neptune. Both have atmospheres made mostly of nitrogen. In 1997, Triton occulted a star and astronomers found that its atmosphere had warmed since the last observations were made in 1989 during the Voyager mission. Back then, Voyager found dark material rising above Triton, indicating possible eruptive activity.

"There could be more massive activity on Pluto, since the changes observed in Pluto's atmosphere are much more severe," Elliot said. "The change observed on Triton was subtle. Pluto's changes are not subtle."

There is no firm evidence that Pluto is volcanically active, but neither is there evidence to rule out that possibility. Even the Hubble Space Telescope can barely make out Pluto's surface.

Elliot added that the process affecting Pluto's temperature is complex. "We just don't know what is causing these effects," he said.

Let's go there

Elliot and others believe this poor understanding of our solar system's tiniest planet is grounds for sending a robot to investigate. Pluto is the only planet not visited by a spacecraft.

NASA has shelved a mission that would explore Pluto and the Kuiper Belt of frozen objects in which it resides.

Congress, however, appears to view the mission as worthy of some funds. A House budget panel this week followed the lead of the Senate in approving $105 million for the mission. If final approval comes, NASA would be compelled to undertake the project.

Interestingly, while Pluto's atmosphere has been growing warmer in recent years, astronomers have argued that a Pluto mission must launch by 2006, lest it miss the opportunity to study Pluto's atmosphere before it completely freezes out for the winter.

Tentative mission plans call for a robotic probe that would not reach Pluto for several years, making a flyby sometime prior to 2020 prior to investigating other objects deeper in the solar system.

Meanwhile, astronomers are looking forward to a space telescope called SOFIA, slated to begin operations in 2004. SOFIA will carry an instrument designed specifically to observe occultations and is expected to be employed when Pluto passes in front of other stars in coming years.

The Pluto observations this summer were funded by NASA, the Research Corporation and the National Science Foundation. Observations were made using the telescopes at the Mauna Kea Observatory, Haleakala, Lick Observatory, Lowell Observatory and the Palomar Observatory.


 

Oceans Temps, Solar Cycles Linked

By Paul Recer

Saturday, March 05, 2005


Associated Press
posted: 10:10 am ET
16 November 2001

WASHINGTON (AP) _ The brightening and dimming of the sun may account for a 1,500-year cycle of cooling and warming on parts of the Earth, a study of ice in the North Atlantic suggests.

Researchers found that a very slight difference in the amount of solar energy reaching the Earth can have a powerful chilling effect on the climate: ice builds up in lands bordering the North Atlantic, the average temperature drops in Europe and North America.

``Whether the whole Earth is affected, we don't know for sure yet, but it is certainly implied,'' said Gerard C. Bond, a researcher at the Lamont-Doherty Earth Observatory of Columbia University in Palisades, N.Y.

``The effect does extend from the high northern latitudes down, maybe even to the tropics,'' said Bond, first author of a study appearing Friday in the journal Science.

The cycle of sunlight intensity roughly follows a 1,500-year pattern, based on analysis of the past 12,000 years. But the difference from the top of the cycle to the bottom is very small, with less than a 0.1 percent difference in energy levels, he said.

Bond and his colleagues believe this is enough to trigger severe climate changes, such as the Little Ice Age, a 490-year period starting in 1400 that dramatically chilled Europe and the North Atlantic.

``The climate system is extremely sensitive to weak forces, such as solar variability,'' Bond said. ``That should make us that much more worried about greenhouse warming.''

Greenhouse warming is thought to be caused by an increase in the atmosphere of carbon dioxide from the burning of fossil fuels, including oil, gas and coal.

The study is an effort to determine if small changes in sunlight over centuries can cause the Earth's climate to warm or cool. Other experts working on the same problem said Bond and his team have made a strong case.

``It shows that the connection is real,'' Jeffrey Park of Yale University said in Science. To David Thomson of Queen's University in Ontario, Canada, it seems like ``a fairly convincing case.''

Bond and his colleagues analyzed small bits of rock that were dropped to the Atlantic floor after being carried to sea by icebergs that broke off glaciers in Iceland and other northern islands.

The rocks fell as the icebergs melted, Bond said. Thus, the farther south the rocks fell, the farther south the icebergs drifted, providing a measure of ocean temperature.

To determine when the rocks were dropped, researchers dated the age of shells deposited at the same time and place.

The 1,500-year cycle of warming and cooling corresponds to data from tree ring studies, another way of measuring the sun's strength over time.

Bond said the sun, at its most energetic, strengthens the Earth's magnetic field, which blocks more cosmic rays, a type of radiation streaking in from deep space.

When cosmic rays hit plants, they cause the formation of certain isotopes, such as carbon-14, that can be measured in ancient tree rings. A tree ring rich in carbon-14 suggests an inactive sun, for example.

Measurements of the iceberg drift and the tree rings showed a similar cycle, Bond said.

``The connection we observed is that the increases in icebergs and drift ice occur at the same times as the increase in (carbon-14), which means the sun was weaker,'' said Bond.

He said the findings also agree with studies that measured the chilling of the Earth based on the advance and retreat of alpine glaciers in Europe.

Bond said the Earth's temperature is still recovering from the Little Ice Age, when ocean temperatures dropped by two to three degrees. That change was enough for ice to jam most of the North Atlantic, closing many ports in the winter and affecting the weather throughout Europe. Rivers that never freeze in modern times were routinely used then for ice skating, Bond said. This means the temperatures SHOULD be going up.

Based on the 1,500-year cycle, Bond said that the Earth's next little ice age could occur about the year 3100, plus or minus 500 years.


 

There Has Been No Global Warming for the Past 70 Years

In our editorial of 15 June 2000 - 'The Global Surface Air Temperature Record Must Be Wrong' - we reviewed a large body of evidence that suggests that the highly-hyped "unprecedented global warming" of the past two decades never actually occurred. Reference authors Craig and Keith Idso, from the Center for the Study of Carbon Dioxide and Global Change.


 

What Warming?

FAEC publishes here an analysis of 1583 temperature records taken from the US Historical Climatology Network database in the United States (along with 1583 graphs and charts of plotted trends) showing that the IPCC's claimed "dramatic warming" does not exist - at least in the United States of America. (4-august-2004)


 

Cooling Everywhere

According to an analysis by scientists at the University of Alabama at Huntsville, July was the coldest worldwide since 1992. In the Northern Hemisphere, July's temperatures were below the 20-year average by 0.14º C and in the Southern Hemisphere by 0.29º C. Both the tropics and Antarctica showed marked coolness. How cold did it get? In Saskatoon on July 29, the overnight low was 0.07 degrees, breaking weather records that had been started in 1892. In Winnipeg on July 23, the overnight low was three degrees, the lowest recorded since 1872. (25-august-2004)


 

Rumble of a coming ice age

Snap climate change

By Margaret Munro

Thursday, March 03, 2005/Friday, October 04, 2002

A remarkable change in the waters of the North Atlantic has thrown what one leading oceanographer is calling a "curve ball" into thinking that the planet will gradually warm due to greenhouse gases in the atmosphere.

Instead, there is a real possibility that global warming may soon trigger the sudden onset of an ice age that could last hundreds of years.

"In just the past year, we have seen ominous signs that we may be headed toward a potentially dangerous threshold," says Dr. Robert Gagosian, president and director of the Woods Hole Oceanographic Institution in Massachusetts. "If we cross it, Earth's climate could switch gears and jump very rapidly -- not gradually -- into a completely different mode of operation.

Gagosian bases his comments on a growing body of evidence that significant changes are underway in the North Atlantic, threatening the ocean current that moderates temperatures in northern climes. Without it London, which is almost as far north as Edmonton, would have much longer, colder winters. And Prince Edward Island potatoes might become a thing of the past.

Talk that climate change might one day trigger the sudden onset of an ice age is not new. But Gagosian believes there is a new urgency, warning that the changes could occur in our lifetime.

And once the changes start, the cooling could be rapid, reducing temperatures by several degrees Celsius over much of the United States, Canada and Europe within a decade.

Gagosian warns rivers, harbours and shipping lanes would freeze much earlier, and transportation, agriculture and fishing would be disrupted.

"In short, the world, and the world economy, would be drastically different," Gagosian says.

His controversial predictions, which he has been making in speeches and has posted on the Wood Hole Web site, are based largely on information garnered from the North Atlantic, where the water is becoming fresher and sinking more slowly.

Igor Yashayaev, at the federal Bedford Institute of Oceanography in Nova Scotia and his colleagues in Britain, the United States and Germany, have found the entire water column of the Labrador Sea has undergone radical change over the past three to four decades.

Data collected during annual spring trips across the Labrador Sea and in waters between Greenland, Iceland and Europe show the North Atlantic, at depths up to 4,000 metres, has become less salty, especially in the last decade.

Scientists are not sure where all the fresh water is coming from. But they suspect much of it is coming the Arctic, where ice has been melting and thinning at an usually high rate.

Gagosian and his colleagues say the flood of fresh water could shut down the so-called Great Ocean Conveyor, the ocean's main heat-circulating system. It drives the Gulf Stream, which carries heat from the tropics north.

By the time water from the Gulf Stream reaches the Labrador and Greenland seas, it is so cool and dense that it sinks into the deep ocean, creating a void that pulls more warm tropical waters north.

Fresh water is more buoyant and less able to sink. Scientists worry that fresher water flowing into the North Atlantic could slow the Gulf Stream or push it south. Or, even worse, shut the conveyor system down completely.

Already, surface water in the Greenland Sea is sinking 20% more slowly that in the 1970s, according to evidence gathered by European scientists. This decreased salinity "is arguably the biggest and most dramatic change in ocean property that has ever been measured in the global ocean," Gagosian says.

"At what per cent will the Ocean Conveyor stop? 25%? 40%? 60%? This is not like a dimmer switch, but more like a light switch. It probably goes from 'on' to 'off,' " he says.

Not everyone, however, is so sure the conveyor is in danger.

"The jury is still out," says Eddy Carmack, an oceanographer at the federal Institute of Ocean Sciences in Sidney, B.C., who is studying changes in the polar and subpolar seas. He is not convinced freshening in the North Atlantic will lead to an abrupt climate change.

"But the stakes are so high, it can not be dismissed," he adds. One thing that can be said with certainty is that the climate is becoming less predictable.

Allyn Clarke, a senior scientist at the Bedford Institute, also cautions against reading too much into the data. He heads the Canadian team that monitors the Labrador Sea.

He says the evidence of freshening in the deep waters of the North Atlantic has been "shocking" to many oceanographers. But like Carmack, he says not enough is known to predict if and when the ocean conveyor could stop. But he says it is a possibility, and one that could trigger an ice age.

Clarke is not as outspoken as his U.S. colleagues, but he says he is in "full sympathy" with Gagosian's report, which stresses the need for better understanding of the changing oceans.

"We are presently doing a global experiment on our climate system with little understanding of which of a number of possible outcomes will result," Clarke says.

Changes in ocean temperatures have been linked to ice ages in the past. About 12,800 years ago, North Atlantic waters cooled dramatically and so did the North Atlantic region.

It took only about a decade to move into a cold spell that lasted close to 1,300 years, Gagosian says.

The most recent shutdown in the North Atlantic circulation is believed to have occurred 500 years ago, wiping out established Norse settlements and vineyards that once thrived in Greenland, he says.

A recent U.S. National Academy of Sciences report, entitled "Abrupt Climate Change: Inevitable Surprises," notes that climate changes have occurred with "startling speed" in the past. And next time, the report said, the cost to agriculture alone could be in the $100- to $250-billion range.

Perhaps the most sobering realization is there will be little anyone can do about it -- short of adapt.

"The climate system can and has moved to new climate states in a matter of decades," Clarke says. "If the system undergoes such a change, we have virtually no idea of how to attempt to stop or reverse the system."


Thursday, October 12, 2006 

The Earth HAS Cooled and WILL Cool

It so happens, the paleontologists say, that variations in the course Earth travels around the Sun and in the tilt of its axis are associated with episodes of global cooling. Their new research on the fossil record shows that the cyclical pattern of these phenomena corresponds to species turnover in rodents and probably other mammal groups as well.

Click HERE for this Story


Tuesday, October 03, 2006 

Global Warming fizzles

A noted hurricane forecaster on Tuesday predicted the Atlantic hurricane season will see just two more tropical storms and no more "major" hurricanes.

Click HERE for the FULL Story


Sunday, October 01, 2006 

Al Gore - Insane!

Al Gore drifts into deeper darkness on the other side of the moon, propelled by such revelations as cigarette smoking is a "significant contributor to global warming"!

Click HERE for FULL Story