Strongest Hurricanes May Triple in Frequency, Study Says

The U.S. Southeast, Mexico, and the Caribbean will be pounded by more very intense hurricanes in the coming decades due to global warming, a new computer model suggests.

Warmer sea surface temperatures—which fuel hurricanes—and shifting wind patterns are expected to strengthen the storms, the study says.

At the same time, rising temperatures should result in fewer weak or middling hurricanes in the western Atlantic.

The study considered what would happen if people kept emitting more greenhouse gases until about 2050 and then started cutting emissions.

"Some refer to this as a middle-of-the-road scenario" for tackling greenhouse gas emissions, said study co-author Thomas Knutson, a research meteorologist with the U.S. National Oceanic and Atmospheric Administration (NOAA).

In this scenario the world became about 4.5 degrees Fahrenheit (2.5 degrees Celsius) warmer than today.

In turn, the western Atlantic Ocean—from Mexico and the Caribbean Sea up to the Carolinas—saw a doubling of category 4 and 5 storms, the most powerful kinds, by 2100. The number of these very intense hurricanes jumped from 24 per decade to 46.

Category 4 storms have sustained wind speeds of 131 to 155 miles (211 to 249 kilometers) an hour. Category 5 hurricanes have winds exceeding 155 miles (249 kilometers) an hour.

"I was quite surprised," said Morris Bender, also a NOAA research meteorologist and the lead author of the new study, to be published tomorrow in the journal Science.

"I didn't expect a doubling. I didn't expect we'd see this much response."

What's more, the most intense hurricanes—category 5 storms—tripled by 2100 in the model.

The new model is perhaps the most sophisticated yet to predict how hurricanes will change as the world warms, study co-author Knutson said.

The researchers combined state-of-the-art global climate simulations with "the hurricane prediction models used by weather forecasters and the [U.S.] Navy," he said.

Combining three models into one tool, the scientists were able to simulate the entire Earth's climate, with realistic hurricanes of all categories romping across the Atlantic.

The modeling method is a first, according to Judith Curry of the Georgia Institute of Technology, who was not involved in the study. "This is an important paper," she said.

Kevin Trenberth of the National Center for Atmospheric Research, in Boulder, Colorado, said there's still a lot of room for improvement in how all of today's climate simulations represent hurricanes and the oceans.

Even so, the new study does bolster an emerging consensus on how climate change will affect hurricanes, added Trenberth, who also was not involved in the research.

"The best information we have now supports the view that tropical storms will likely decrease in number," he said. "But the risk of category 4 and 5 storms could increase."

Signs From Earth: Now What?

"One. Two. Three. Lift!" barks Cathy Whitlock, a fossil pollen expert and paleoclimatologist at the University of Oregon. She and the three of us—two of her students and I—tighten our grips on the cold metal tube of a lake-bed drilling rig and heave. "Again," she commands. Slowly, inch by inch and groan by groan, the coring barrel that Whitlock and her students had manhandled into the marshy shore of Little Lake, a blue jewel of water in Oregon's central Coast Range, emerges from the mud.

"Once more," orders Whitlock. We bend to the task and at last free the barrel from the muck. Whitlock has extracted a couple hundred similar cores from the deep sediments of this lake, but she beams like a kid getting her first bike as she slides her latest sample of old mud, five centimeters (two inches) thick and a meter (3.3 feet) long, out of the barrel.

"Oh, that's a lovely core," she says. To me it looks about as interesting as a Tootsie Roll. But to Whitlock's trained eye even the chocolate hue of the mud holds a story. "That rich brown color tells you it's full of organic matter—especially pollen," she says, slicing the core in half lengthwise with her pocketknife. "You can't see the pollen without a microscope, but it's there."

And in that pollen lie clues to one of the greatest puzzles facing researchers like Whitlock: What has caused—and will cause again—the sudden climate changes that our Earth periodically undergoes? Not the 100,000-year fluctuations between a glaciated and a warmer Earth that have occurred for the past million years or so, but the more rapid shifts that scientists have recently identified when the Earth switched suddenly from frozen ice age to picnic-warm and back again. How often and how quickly have such dramatic changes happened? Perhaps most important, what do these past abrupt reversals tell us about the direction of Earth's climate today and in the future?

To answer such questions, scientists are busy unearthing signs of ancient climate in a surprising array of sources: glacial ice and moraines, stalagmites from caverns, tree rings and corals, dust and sand dunes, and the microscopic shells of organisms buried in deep-ocean sediments. Others, hoping to piece together the climate of the more recent past, turn to human records, using archaeological inscriptions, vintner and gardening diaries, and ship captains' logs. "We need both human and natural records," explains Ohio State University glaciologist Lonnie Thompson, who specializes in retrieving ice cores from the dwindling glaciers on tropical mountains. "We want to understand how the climate worked before and after people appeared. That's the only way we'll figure out what impact people have on climate, how much we're responsible for the way it's changing now."

Just how swiftly climate changes can occur is clear from Whitlock's study of her Little Lake cores. Those like the ones we drilled are stored at her university lab. Each meter (3.3 feet) of mud contains about 2,300 years of pollen grains from trees, grasses, and flowering plants. To find the pollen in the mud, Whitlock takes smudges from every core at set intervals, then puts the mud in a chemical bath that eats away everything but the thousands of previously invisible pollen grains. She places a droplet of the pollen residue on a slide and then "reads" about 300 grains, identifying the species of each one—a process that allows her to trace how the vegetation in the Coast Range changed during the climatic variations of the past.

Haiti Earthquake, Deforestation Heighten Landslide Risk

The combination of widespread deforestation and the recent earthquake inHaiti could lead to more landslides in the already hard-hit country, scientists say 

Many of Haiti's people, the poorest in the Americas, routinely cut down trees for fuel—either to burn "raw" or turn into charcoal.

As a result, the destruction of Haiti's natural forests is almost total, making the Caribbean country one of the most deforested in the world.

As Haiti's trees have disappeared, landslides have become a major concern, especially during the rainy season, and the destabilizing effects of an earthquake on soil only worsen the problem.

Forest canopies serve as natural buffers against wind and rain, and the deep roots of trees help keep the granular soil from shifting.

"If you remove the trees, you have no buffer. So the water"—and soil—"tends to very quickly move downhill," said Mark Ashton, a professor at the Yale School of Forestry and Environmental Studies.

During an earthquake, hillside stability is further threatened as the ground is shaken.

"Anywhere you have strong motion and steep terrain, you have extremely high risk of slope failure and landslides, and they can be extremely large," said Colin Stark, a geophysicists at the Lamont-Doherty Earth Observatory in New York.

Among the rare bright spots for Haiti this week are  that its capital, Port-au-Prince, is on relatively flat land—making the landslide threat one less thing to worry about—and that the earthquake struck during the dry season.

"The worst kinds of landslides would be if you had an earthquake on rain-soaked soil," Yale's Ashton said.

The surrounding hilly regions may not be so lucky, he added. Even without landslides, post-earthquake pictures show collapsed houses sliding downhill.

"It's where foothills are that the worst landslides will occur," he said. "That's also where people tend to build their houses."

AIDS Virus Traveled to Haiti, Then U.S., Study Says

HIV went directly from Africa to Haiti, then spread to the United States and much of the rest of the world beginning around 1969, suggests an international team of researchers.

The findings settle a key debate on the history and transmission route of the deadly virus, the scientists say.

Even before HIV was identified as the cause of AIDS, Haiti's role in the disease epidemic had been hotly debated.

When AIDS was officially recognized in 1981 in the U.S., for instance, the unusually high prevalence of the disease in Haitian immigrants fueled speculation that the Caribbean island was the source of the mysterious illness.

Another theory held that the AIDS epidemic spread from the U.S. in the mid-1970s after Haiti became a popular destination for sex tourism.

Scientists led by Michael Worobey, an evolutionary biologist at the University of Arizona, Tucson, tried to solve the puzzle by tracing back the family history of the virus subtype blamed for the epidemic in North America.

The findings suggest that native Haitians carried the disease back to their island from Africa soon after the virus's emergence there.

HIV is commonly transmitted through tainted blood transfusions, dirty needles, and unprotected sex. Infections often lead to a life-threatening condition in which the body's immune defenses are systematically disabled.

Two species of HIV can infect humans—HIV-1 and HIV-2. The former is more virulent, more easily transmitted, and accounts for the lion's share of global HIV infections. HIV-2 is less infectious and is largely confined to parts of Western Africa.

Based on differences in one of the nine genes that make up the virus, HIV-1 is placed in three major groups. The most prevalent, Group M, has eight geographically distinct subtypes.

Worobey and his colleagues looked at subtype B. Though it is found mainly in North America and Europe, the strain is present in the most number of countries.

The researchers analyzed tissue samples from five Haitian AIDS patients collected in 1982 and 1983. All five had then recently immigrated to the U.S. and were among the first recognized victims of AIDS.

A family tree constructed from the HIV-1 genes of the five Haitians and subtype B gene sequences from 19 other countries place the Haitian virus at the root of all branches.

"This is strong evidence that HIV-1 subtype B arrived and began spreading in Haiti before it did elsewhere," Worobey said.

It is generally thought that the virus arrived with Haitian professionals returning from Zaire (now the Democratic Republic of the Congo) following a wave of nationalism there in the 1960s.

Using advanced statistical techniques, Worobey and his colleagues estimated that the subtype B strain reached Haiti sometime around 1966 and the United States around 1969.

"Until AIDS was initially recognized in 1981, the virus was cryptically [hiddenly] circulating in a sophisticated medical environment for the better part of 12 years," Worobey said.

Beatrice Hahn is a microbiologist at the University of Alabama in Birmingham who was not involved with the study.

"The paper is a nice piece of evolutionary sleuthing,'' she said. "It shows how chance events can shape a major epidemic and that one virus introduced under the right circumstances can create major havoc."

"The findings are significant," added Robert Garry, a microbiologist at Tulane University. They indicate "an important lineage of subtype B HIV was present in Haiti, which eventually spread elsewhere," he added.

But he is not fully convinced that a Haitian origin is the only explanation for subtype-B strains in the Americas, however.

It is quite likely that other B lineages appeared in the Americas prior to and in all likelihood independently of the Haitian lineage, he said.

"It is possible that HIV made many incursions into the United States. Most of these likely never spread or spread cryptically for a while and burned out," he added. "The one discussed in this paper appears to have been the bomb that actually went off."

Study leader Worobey, a former forest firefighter, likes to use a wildfire analogy.

"It is like a forest fire, it often produces sparks that fly out in front of a fire. Some of those sparks ... die out. But every once in a while one of those sparks ... can start a new wildfire. And that is what we are seeing in this case."

Haiti Earthquake "Strange," Strongest in 200 Years

The magnitude 7 earthquake that struck Haiti yesterday is the strongest earthquake to hit the region in more than two centuries, geologists say.

While earthquakes are not uncommon in the Caribbean island country, the recent Haiti earthquake's intensity surprised experts.

"It's quite strange" from a historical perspective, said Julie Detton, a geophysicist with the U.S. Geological Survey.

Haiti is part of the island of Hispaniola, which also hosts the Dominican Republic. The last major earthquake to strike Haiti's side of the island was in 1860.

Yesterday's initial earthquake, which struck at about 5 p.m. local time yesterday, spawned dozens of aftershocks, about 15 of which were magnitude 5 or greater.

Whether the earthquake could trigger other major quakes is not known.

"It's not something that we can project is going to happen," Detton said.

"But definitely if you're moving two [plates] in one area, you're building up stress and strain in another."

The Haiti earthquake was caused by the release of seismic stresses that had built up around two tectonic plates.

The motions of these plates create what are known as strike-slip faults, where two sections of Earth's crust are grinding past each other in opposite directions.

"The Caribbean plate is moving eastward with respect to the North American plate," Detton said.

When the stresses along the fault lines reach a certain point, they can be released in bursts of energy that cause earthquakes, although it's unclear when the energy will be discharged as a series of small quakes or as one big temblor.

Since Haiti is very close to the boundary where the Caribbean and North American plates meet, fault lines linked to the plates' movements run right through the country, Detton said.

In fact, the epicenter of the earthquake was about 10 miles (16 kilometers) southwest of Haiti's capital city, Port-au-Prince. (See a Haiti map.)

In addition, the Haiti earthquake was very shallow, being centered just 6.2 miles (10 kilometers) below Earth's surface.

This put impoverished Port-au-Prince close to the most intense shaking, contributing to the scale of the devastation: Thousands are feared dead and countless buildings have collapsed, from schools and hotels to the Haitian Parliament and local UN headquarters.

The American Red Cross estimates that the Haiti earthquake may have affected about three million people in total.

Google Defends Against Large Scale Chinese Cyber Attack: May Cease Chinese Operations

Google is releasing some information about these attacks to the public. The company says that a minimal amount of user information was compromised, but has come to the alarming conclusion that the attacks were targeting the information of Chinese human rights activists. Google found that these attacks were not just going after Google’s data, but were also targeting at least twenty other major companies spanning sectors including Internet, finance, chemicals, and more. Google has also discovered that phishing attacks have been used to compromise the Gmail accounts of Chinese human rights activists around the world.

In light of the attacks, and after attempts by the Chinese government to further restrict free speech on the web, Google has decided it will deploy a fully uncensored version of its search engine in China. This is a major change: since January 2006, Google has made concessions to the Chinese government and offered a censored (and highly controversial) version of its search engine at Google.cn. Google isn’t playing that game any longer. Should the Chinese government decide that an uncensored engine is illegal, then Google may cease operations in China entirely.  We have included Google’s blog posts about the decision in their entirety below.

Like many other well-known organizations, we face cyber attacks of varying degrees on a regular basis. In mid-December, we detected a highly sophisticated and targeted attack on our corporate infrastructure originating from China that resulted in the theft of intellectual property from Google. However, it soon became clear that what at first appeared to be solely a security incident–albeit a significant one–was something quite different.

First, this attack was not just on Google. As part of our investigation we have discovered that at least twenty other large companies from a wide range of businesses–including the Internet, finance, technology, media and chemical sectors–have been similarly targeted. We are currently in the process of notifying those companies, and we are also working with the relevant U.S. authorities.

Second, we have evidence to suggest that a primary goal of the attackers was accessing the Gmail accounts of Chinese human rights activists. Based on our investigation to date we believe their attack did not achieve that objective. Only two Gmail accounts appear to have been accessed, and that activity was limited to account information (such as the date the account was created) and subject line, rather than the content of emails themselves.

Third, as part of this investigation but independent of the attack on Google, we have discovered that the accounts of dozens of U.S.-, China- and Europe-based Gmail users who are advocates of human rights in China appear to have been routinely accessed by third parties. These accounts have not been accessed through any security breach at Google, but most likely via phishing scams or malware placed on the users’ computers.

We have already used information gained from this attack to make infrastructure and architectural improvements that enhance security for Google and for our users. In terms of individual users, we would advise people to deploy reputable anti-virus and anti-spyware programs on their computers, to install patches for their operating systems and to update their web browsers. Always be cautious when clicking on links appearing in instant messages and emails, or when asked to share personal information like passwords online. You can read more here about our cyber-security recommendations. People interested wanting to learn more about these kinds of attacks can read this U.S. government report (PDF), Nart Villeneuve’s blog and this presentation on the GhostNet spying incident.

We have taken the unusual step of sharing information about these attacks with a broad audience not just because of the security and human rights implications of what we have unearthed, but also because this information goes to the heart of a much bigger global debate about freedom of speech. In the last two decades, China’s economic reform programs and its citizens’ entrepreneurial flair have lifted hundreds of millions of Chinese people out of poverty. Indeed, this great nation is at the heart of much economic progress and development in the world today.

We launched Google.cn in January 2006 in the belief that the benefits of increased access to information for people in China and a more open Internet outweighed our discomfort in agreeing to censor some results. At the time we made clear that “we will carefully monitor conditions in China, including new laws and other restrictions on our services. If we determine that we are unable to achieve the objectives outlined we will not hesitate to reconsider our approach to China.”

These attacks and the surveillance they have uncovered–combined with the attempts over the past year to further limit free speech on the web–have led us to conclude that we should review the feasibility of our business operations in China. We have decided we are no longer willing to continue censoring our results on Google.cn, and so over the next few weeks we will be discussing with the Chinese government the basis on which we could operate an unfiltered search engine within the law, if at all. We recognize that this may well mean having to shut down Google.cn, and potentially our offices in China.

The decision to review our business operations in China has been incredibly hard, and we know that it will have potentially far-reaching consequences. We want to make clear that this move was driven by our executives in the United States, without the knowledge or involvement of our employees in China who have worked incredibly hard to make Google.cn the success it is today. We are committed to working responsibly to resolve the very difficult issues raised.

Posted by David Drummond, SVP, Corporate Development and Chief Legal Officer

Here’s a second post, from the Google Enterprise Blog:

Many corporations and consumers regularly come under cyber attack, and Google is no exception. We recently detected a cyber attack targeting our infrastructure and that of at least 20 other publicly listed companies. This incident was particularly notable for its high degree of sophistication. We believe Google Apps and related customer data were not affected by this incident. Please read more about our public response on the Official Google Blog.

This attack may understandably raise some questions, so we wanted to take this opportunity to share some additional information and assure you that Google is introducing additional security measures to help ensure the safety of your data.

This was not an assault on cloud computing. It was an attack on the technology infrastructure of major corporations in sectors as diverse as finance, technology, media, and chemical. The route the attackers used was malicious software used to infect personal computers. Any computer connected to the Internet can fall victim to such attacks. While some intellectual property on our corporate network was compromised, we believe our customer cloud-based data remains secure.

While any company can be subject to such an attack, those who use our cloud services benefit from our data security capabilities. At Google, we invest massive amounts of time and money in security. Nothing is more important to us. Our response to this attack shows that we are dedicated to protecting the businesses and users who have entrusted us with their sensitive email and document information. We are telling you this because we are committed to transparency, accountability, and maintaining your trust.

Google’s China Stance: More about Business than Thwarting Evil

Writing about China as an American is always tricky, but nowhere near as tricky as what an American company faces doing business there. Let me say upfront, I don’t envy Google. The company has had more success in China than a lot of other big Valley names, but isn’t and will likely never be the market leader. And to get that far, many in the West feel Google has had to compromise its “do-no-evil” ethics by agreeing to some of the government’s censorship rules. Google has been damned either way: China is too big of a market to ignore, but getting as far as they have has come at a steep price to their reputation and international (read: Western) integrity.

Enter the now famous blog post (that was notably, only on the English-language site) saying that Google was no longer playing by the Chinese government’s rules and was prepared to close down Chinese operations if it came to that. Valley elites erupted into applause on Twitter and blogs saying Google was showing more backbone than the US government and was a model of integrity for the world.

I’ll give Google this much: They’re taking a bad situation and making something good out of it, both from a human and business point of view. I’m not saying human rights didn’t play into the decision, but this was as much about business. Lest we get too self-righteous as Westerners, we should remember three things:

1. Google’s business was not doing well in China. Does anyone really think Google would be doing this if it had top market share in the country? For one thing, I’d guess that would open them up to shareholder lawsuits. Google is a for-profit, publicly-held company at the end of the day. When I met with Google’s former head of China Kai-fu Lee in Beijing last October, he noted that one reason he left Google was that it was clear the company was never going to substantially increase its market share or beat Baidu. Google has clearly decided doing business in China isn’t worth it, and are turning what would be a negative into a marketing positive for its business in the rest of the world.

2. Google is ready to burn bridges. This is not how negotiations are done in China, and Google has done well enough there to know that. You don’t get results by pressuring the government in a public, English-language blog post. If Google were indeed still working with the government this letter would not have been posted because it has likely slammed every door shut, as a long-time entrepreneur in China Marc van der Chijs and many others said on Twitter. This was a scorched earth move, aimed at buying Google some good will in the rest of the world; Chinese customers and staff were essentially just thrown under the bus.

3. This is only going to be a trickier issue in the next decade. Think the Shandaacquisition of Mochi Media was an isolated event? Think again. Chinese Web companies are building huge cash hoards and valuable stock currencies and it’s still a comparatively young Web market. Increasingly, these companies could be likely buyers of US startups—not the other way around. Will the Valley’s rhetoric stick then?

This may be the most shocking part: In retrospect Yahoo has played China far better than Google. It pulled out of the country years ago, knowing it wouldn’t win and owns nearly 40% of the Alibaba, a company that very definitely knows how to grow in China. Entrepreneur and angel investor in China Bill Bishop —who hasn’t always agreed with my China coverage in the past—pointed this out, adding “Not often Yahoo looks smarter than Google.”

"Blue Moon" to Shine on New Year's Eve

For the first time in almost 20 years, a bright "blue moon" will grace New Year's Eve celebrations worldwide.
If the skies are clear, revelers looking up at midnight will get an eyeful of the second full moon of the month—commonly called a blue moon. The last time a blue moon appeared on New Year's Eve was in 1990, and it won't happen again until 2028.

A blue moon isn't actually blue—as commonly defined, the name reflects the relative rarity of two full moons in a month and is linked to the saying "once in a blue moon."

With this New Year's Eve blue moon, "there is nothing scientific about it, and it has no astronomical significance," said Mark Hammergren, a staff astronomer at the Adler Planetarium in Chicago, Illinois.

"But I believe it does give us some insight into history and makes us think of how our calendar system has derived from motions of objects in the sky."

The popular definition of a blue moon isn't the only one—and it's one that's based on an editorial error, astronomers contend.

The widespread definition of the second full moon in a month stems from errors made in an astronomy magazine, when a writer misinterpreted how the term was used in theMaine Farmer's Almanac.

Later studies of almanacs published from 1819 to 1962 revealed that the term "blue moon" actually refers to the "extra" full moon that can occur in a year due to differences between the calendar year and the astronomical year.

Most years on average have 12 full moons, with 1 appearing each month.

That's because the lunar month—the time it takes the moon to cycle through its phases—corresponds closely to the calendar month.

But the calendar year is actually based on the solar cycle, or the time it takes Earth to make one trip around the sun. This means a year is not evenly divisible by lunar months, so every three years or so there are 13 full moons.

The farmer's almanac further divided the year into four seasons, with each season lasting three months. When a given season saw four full moons, the almanac dubbed the third moon as a blue moon.

Ultimately, a blue moon as defined by the calendar isn't that rare, added Hammergren. The term's significance instead lies in the way it links people to the motions of the cosmos.

"Just being able to recognize that we can have a full moon twice in a month and have [folklore] attached really highlights the fact that humans have been astronomers their entire existence," he said.

Before the editorial error, the term "blue moon" more often referred to the rare instances when the moon actually seemed to turn blue, as can happen under certain atmospheric conditions.

"After a forest fire or volcanic eruption, there may be enough particulate matter in the air so that the moon can take on a bluish tinge," Hammergren said.

For instance, a "true" blue moon occurred in 1950 after a large forest fire in Canada blew smoke across most of the Northern Hemisphere.

Another appeared in 1980 after the last major eruption of Mount St. Helens, which sent tons of ash into the upper atmosphere.

Although rumblings at the Mayon Volcano in the Philippines seem to signal a major eruption is imminent, experts don't think Mayon's current output will make this New Year's Eve full moon turn blue.

Even if the 2009 New Year's Eve blue moon has astronomers scoffing, nighttime partygoers may still get moonstruck.

Rising in the east at sunset, the New Year's Eve full moon will reach its highest point at midnight, noted Jack Horkheimer, director of the Miami Space-Transit Planetarium and host of PBS television's long-running show Star Gazer.

"Full moons around winter solstice rise their highest for the entire year," Horkheimer added.

"Even if you are downtown in a large city, if it is clear at the stroke of midnight the moon will be very visible if you look up."

In any location, the high, silvery orb will seem like a floodlight cast on the landscape, added Horkheimer, who is organizing a national moon-howling contest around this year's blue moon.

"This is especially true where the ground is covered with a blanket of snow. There is nothing quite so spectacular as a snow-covered scene under a December full moon at midnight."

World's Biggest Cave Found in Vietnam

A massive cave recently uncovered in a remote Vietnamese jungle is the largest single cave passage yet found, a new survey shows.

At 262-by-262 feet (80-by-80 meters) in most places, the Son Doong cave beats out the previous world-record holder, Deer Cave in the Malaysian section of the island of Borneo.

Deer Cave is no less than 300-by-300 feet (91-by-91 meters), but it's only about a mile (1.6 kilometers) long.

By contrast, explorers walked 2.8 miles (4.5 kilometers) into Son Doong, in Phong Nha-Ke Bang National Park, before being blocked by seasonal floodwaters—and they think that the passage is even longer.

In addition, for a couple of miles Son Doong reaches more than 460-by-460 feet (140-by-140 meters), said Adam Spillane, a member of the British Cave Research Association expedition that explored the massive cavern.

Spillane was in the first of two groups to enter the cave. His team followed the passage as far as a 46-foot-high (14-meter-high) wall.

"The second team that went in got flooded out," he said. "We're going back next year to climb that wall and explore the cave further."

A local farmer, who had found the entrance to the Son Doong cave several years ago, led the joint British-Vietnamese expedition team to the cavern in April.

The team found an underground river running through the first 1.6 miles (2.5 kilometers) of the limestone cavern, as well as giant stalagmites more than 230 feet (70 meters) high.

The explorers surveyed Son Doong's size using laser-based measuring devices.

Such modern technology allows caves to be measured to the nearest millimeter, said Andy Eavis, president of the International Union of Speleology, the world caving authority, based in France.

"With these laser-measuring devices, the cave sizes are dead accurate," he said. "It tends to make the caves smaller, because years ago we were estimating, and we tended to overestimate."

Eavis, who wasn't involved in the survey, agreed that the new findings confirm Son Doong's record status—despite the fact that he had discovered Borneo's now demoted Deer Cave.

"This one in Vietnam is bigger," Eavis conceded.

However the British caver can still claim the discovery of the world's largest cave chamber, Sarawak Chamber, also in Borneo.

"That is so large it may not actually be beaten," he said. "It's three times the size of Wembley Stadium" in London.

Son Doong had somehow escaped detection during previous British caving expeditions to the region, which is rich in limestone grottos.

"The terrain in that area of Vietnam is very difficult," said expedition team member Spillane.

"The cave is very far out of the way. It's totally covered in jungle, and you can't see anything on Google Earth," he added, referring to the free 3-D globe software.

"You've got to be very close to the cave to find it," Spillane said. "Certainly, on previous expeditions, people have passed within a few hundred meters of the entrance without finding it."

The team was told that local people had known of the cave but were too scared to delve inside.

"It has a very loud draft and you can hear the river from the cave entrance, so it is very noisy and intimidating," Spillane said.

Of more concern to the caving team were the poisonous centipedes that live in Son Doong.

The explorers also spotted monkeys entering through the roof of the cave to feed on snails, according to Spillane.

"There are a couple of skylights about 300 meters [985 feet] above," he said. "The monkeys are obviously able to climb in and out."

A biologist will accompany the team on its return visit next year to survey the cave's subterranean wildlife.

Eavis, of the International Union of Speleology, added that there are almost certainly bigger cave passages awaiting discovery around the world.

"That's the fantastic thing about caving," he said.

Satellite images hint, for example, that caves even larger than Son Doong lie deep in the Amazon rain forest, he said.

Isaac Newton: Who He Was, Why Google Apples Are Falling

Today on the Google home page, an animated apple is falling, over and over, with a satisfying plunk—a 367th birthday tribute to SirIsaac Newton.

The English scientist was born especially tiny but grew into a massive intellect and still looms large, thanks to his findings on gravity, light, motion, mathematics, and more.

Legend has it that Isaac Newton formulated gravitational theory in 1665 or 1666 after watching an apple fall and asking why the apple fell straight down, rather than sideways or even upward.

"He showed that the force that makes the apple fall and that holds us on the ground is the same as the force that keeps the moon and planets in their orbits," said Martin Rees, President of Britain's Royal Society, the United Kingdom's national academy of science, which was once headed by Newton himself.

"His theory of gravity wouldn't have got us global positioning satellites," said Jeremy Gray, a mathematical historian at the Milton Keynes, U.K-based Open University. "But it was enough to develop space travel."

Born two to three months prematurely on January 4, 1643, in a hamlet in Lincolnshire, England, Isaac Newton was a tiny baby who, according to his mother, could have fit inside a quart mug. A practical child, he enjoyed constructing models, including a tiny mill that actually ground flour—powered by a mouse running in a wheel.

Admitted to the University of Cambridge on 1661, Newton at first failed to shine as a student.

In 1665 the school temporarily closed because of a bubonic plague epidemic and Newton returned home to Lincolnshire for two years. It was then that the apple-falling brainstorm occurred, and he described his years on hiatus as "the prime of my age for invention."

Despite his apparent affinity for private study, Newton returned to Cambridge in 1667 and served as a mathematics professor and in other capacities until 1696.

Decoding gravity was only part of Newton's contribution to mathematics and science. His other major mathematical pre-occupation was calculus, and along with German mathematician Gottfried Leibniz, Newton developed differentiation and integration—techniques that remain fundamental to mathematicians and scientists.

Meanwhile, his interest in optics led him to propose, correctly, that white light is actually the combination of light of all the colors of the rainbow. This, in turn, made plain the cause of chromatic aberration—inaccurate color reproduction—in the telescopes of the day.

To solve the problem, Newton designed a telescope that used mirrors rather than just glass lenses, which allowed the new apparatus to focus all the colors on a single point—resulting in a crisper, more accurate image. To this day, reflecting telescopes, including the Hubble Space Telescope, are mainstays of astronomy 

Following his apple insight, Newton developed the three laws of motion, which are, in his own words:

• Newton's Law of Inertia: Every object persists in its state of rest or uniform motion in a straight line unless it is compelled to change that state by forces impressed upon it.

• Newton's Law of Acceleration: Force is equal to the change in momentum (mV) per change in time. For a constant mass, force equals mass times acceleration [expressed in the famous equation F = ma].

• Newton's Law of Action and Reaction: For every action, there is an equal and opposite reaction.

Newton published his findings in 1687 in a book called Philosophiae Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy) commonly known as the Principia.

"Newton's Principia made him famous—few people read it, and even fewer understood it, but everyone knew that it was a great work, rather like Einstein's Theory of Relativity over two hundred years later," writes mathematician Robert Wilson of the Open University in an article on a university Web site.

Despite his wealth of discoveries Isaac Newton wasn't well liked, particularly in old age, when he served as the head of Britain's Royal Mint, served in Parliament, and write on religion, among other things.

"As a personality, Newton was unattractive—solitary and reclusive when young, vain and vindictive in his later years, when he tyrannized the Royal Society and vigorously sabotaged his rivals," the Royal Society's Rees said.

Sir David Wallace, director of the Isaac Newton Institute for Mathematical Sciences in Cambridge, U.K., added, "He was a complex character, who also pursued alchemy"—the search for a method to turn base metals into gold—"and, as Master of the Mint, showed no clemency towards coiners [counterfeiters] sentenced to death."

In 1727, at 84, Sir Isaac Newton died in his sleep and was buried with pomp and ceremony in Westminster Abbey in London.

"Lost" Amazon Complex Found; Shapes Seen by Satellite

Hundreds of circles, squares, and other geometric shapes once hidden by forest hint at a previously unknown ancient society that flourished in the Amazon, a new study says.

Satellite images of the upper Amazon Basin taken since 1999 have revealed more than 200 geometric earthworks spanning a distance greater than 155 miles (250 kilometers).

Now researchers estimate that nearly ten times as many such structures—of unknown purpose—may exist undetected under the Amazon's forest cover.

At least one of the sites has been dated to around A.D. 1283, although others may date as far back as A.D. 200 to 300, said study co-author Denise Schaan, an anthropologist at the Federal University of Pará in Belém, Brazil.

The discovery adds to evidence that the hinterlands of the Amazon once teemed with complex societies, which were largely wiped out by diseases brought to South America by European colonists in the 15th and 16th centuries, Schaan said.

Since these vanished societies had gone unrecorded, previous research had suggested that soils in the upper Amazon were too poor to support the extensive agriculture needed for such large, permanent settlements.

"We found that this picture is wrong," Schaan said. "And there is a lot more to discover in these places."

The newfound shapes are created by a series of trenches about 36 feet (11 meters) wide and several feet deep, with adjacent banks up to 3 feet (1 meter) tall. Straight roads connect many of the earthworks.

Preliminary excavations at one of the sites in 2008 revealed that some of the earthworks were surrounded by low mounds containing domestic ceramics, charcoal, grinding-stone fragments, and other evidence of habitation.

But who built the structures and what functions they served remains a mystery. Ideas range from defensive buildings to ceremonial centers and homes, the study authors say.

It's also possible the structures served different purposes over time, noted William Woods, a geographer and anthropologist at the University of Kansas in Lawrence who was not involved in the research.

"For example," he said, "in Lawrence there's a Masonic temple—it is now a bar. There was a bank—it is now a restaurant called Tellers. These things happen."

What most surprised the research team is that the earthworks appear in both the region's floodplains and the uplands.

In general, the Amazon's fertile floodplains have been popular sites for ancient civilizations, while the sparser uplands have been thought to be largely devoid of people, the researchers say.

What's more, the earthworks in both regions are of a similar style, suggesting they were built by the same society.

"In Amazonian archaeology you always have this idea that you find different peoples in different ecosystems," study co-author Schaan said.

"And so it was kind of odd to have a culture that would take advantage of different ecosystems and expand over such a large region."

The uplands sites appear to have been home to as many as 60,000 people, Schaan and her colleagues suggest in their paper, published this month in the journal Antiquity.

That figure is based on estimates of the social organization and labor that would have been required to build the structures hinted at by the remaining earthworks.

According to the University of Kansas' Woods, the population estimate is reasonable, albeit rough, since so little is known about these complexes.

Answers may emerge as researchers continue to excavate the newfound shapes in the coming years.

But Woods is impressed by the possibility that so many people might have once lived in a region long thought uninhabited.

"Traditionally, if you would have asked an anthropologist or archaeologist how many people lived [in these Amazon uplands], they'd say almost zero," he said.

"And so this is astounding that there is 60,000 people making a go of it where there aren't supposed to be any."