Further to my series on Extinction Level Events—specifically, Comets & The Oort Cloud—I found this amazing video today:
On October 15th, bloggers around the web will unite to put a single important issue on everyone’s mind—the environment. Every blogger will post about the environment in their own way and relating to their own topic. Our aim is to get everyone talking towards a better future.
Future generations may well have occasion to ask themselves, "What were our parents thinking? Why didn't they wake up when they had a chance?" We have to hear that question from them, now. —Al Gore, An Inconvenient Truth
The UN Intergovernmental Panel on Climate Change is due to release a report in Paris on Friday entitled Climate Change 2007 in which 2,500 scientists from 130 countries unequivocally state that the current trend towards potentially catastrophic global warming has been induced by human activity, which began with the dramatic increase in fossil fuel use during the Industrial Revolution of the mid-19th century....
The report is not without its critics in the scientific community. One senior British climate expert quoted in The Observer warned that the report’s predictions are relatively rosy, given its painstaking consensus process: “The really chilling thing about the IPCC report is that it is the work of several thousand climate experts who have widely differing views about how greenhouse gases will have their effect. Each paragraph of this report was therefore argued over and scrutinized intensely. Only points that were considered indisputable survived this process. This is a very conservative document—that's what makes it so scary.” —Source
Ancient ice shelf breaks free from Canadian Arctic
POSTED: 11:31 a.m. EST, December 29, 2006
• Scientist: "Disturbing event" shows "we are crossing climate thresholds"
• Researchers using satellite images discovered 2005 event
• Collapse picked up by earthquake monitors 155 miles away
TORONTO, Ontario (AP)—A giant ice shelf the size of 11,000 football fields has snapped free from Canada's Arctic, scientists said.
The mass of ice broke clear 16 months ago from the coast of Ellesmere Island, about 800 kilometers (497 miles) south of the North Pole, but no one was present to see it in Canada's remote north.
Scientists using satellite images later noticed that it became a newly formed ice island in just an hour and left a trail of icy boulders floating in its wake. (Watch the satellite images that clued in ice watchers)
Warwick Vincent of Laval University, who studies Arctic conditions, traveled to the newly formed ice island and could not believe what he saw.
"This is a dramatic and disturbing event. It shows that we are losing remarkable features of the Canadian North that have been in place for many thousands of years. We are crossing climate thresholds, and these may signal the onset of accelerated change ahead," Vincent said Thursday.
In 10 years of working in the region he has never seen such a dramatic loss of sea ice, he said.
The collapse was so powerful that earthquake monitors 250 kilometers (155 miles) away picked up tremors from it.
The Ayles Ice Shelf, roughly 66 square kilometers (41 square miles) in area, was one of six major ice shelves remaining in Canada's Arctic.
Scientists say it is the largest event of its kind in Canada in 30 years and point their fingers at climate change as a major contributing factor.
"It is consistent with climate change," Vincent said, adding that the remaining ice shelves are 90 percent smaller than when they were first discovered in 1906.
"We aren't able to connect all of the dots... but unusually warm temperatures definitely played a major role."
Laurie Weir, who monitors ice conditions for the Canadian Ice Service, was poring over satellite images in 2005 when she noticed that the shelf had split and separated.
Weir notified Luke Copland, head of the new global ice lab at the University of Ottawa, who initiated an effort to find out what happened.
Using U.S. and Canadian satellite images, as well as data from seismic monitors, Copland discovered that the ice shelf collapsed in the early afternoon of August 13, 2005.
"What surprised us was how quickly it happened," Copland said. "It's pretty alarming.
"Even 10 years ago scientists assumed that when global warming changes occur that it would happen gradually so that perhaps we expected these ice shelves just to melt away quite slowly, but the big surprise is that for one they are going, but secondly that when they do go, they just go suddenly, it's all at once, in a span of an hour."
Within days, the floating ice shelf had drifted a few miles (kilometers) offshore. It traveled west for 50 kilometers (31 miles) until it finally froze into the sea ice in the early winter.
The Canadian ice shelves are packed with ancient ice that dates back over 3,000 years. They float on the sea but are connected to land.
Derek Mueller, a polar researcher with Vincent's team, said the ice shelves get weaker and weaker as the temperature rises. He visited Ellesmere's Ward Hunt Ice Shelf in 2002 and noticed it had cracked in half.
"We're losing our ice shelves, and this a feature of the landscape that is in danger of disappearing altogether from Canada," Mueller said. "In the global perspective Antarctica has many ice shelves bigger than this one, but then there is the idea that these are indicators of climate change."
The spring thaw may bring another concern as the warming temperatures could release the ice shelf from its Arctic grip. Prevailing winds could then send the ice island southwards, deep into the Beaufort Sea.
"Over the next few years this ice island could drift into populated shipping routes," Weir said. "There's significant oil and gas development in this region as well, so we'll have to keep monitoring its location over the next few years."
The main ice covered landmass is Antarctica at the South Pole, with about 90 percent of the world's ice (and 70 percent of its fresh water). Antarctica is covered with ice an average of 2,133 meters (7,000 feet) thick. If all of the Antarctic ice melted, sea levels around the world would rise about 61 meters (200 feet). But the average temperature in Antarctica is -37°C, so the ice there is in no danger of melting. In fact in most parts of the continent it never gets above freezing.
There is a significant amount of ice covering Greenland, which would add another 7 meters (20 feet) to the oceans if it melted. Because Greenland is closer to the equator than Antarctica, the temperatures there are higher, so the ice is more likely to melt.
But there might be a less dramatic reason than polar ice melting for the higher ocean level—the higher temperature of the water. Water is most dense at 4 degrees Celsius. Above and below this temperature, the density of water decreases (the same weight of water occupies a bigger space). So as the overall temperature of the water increases it naturally expands a little bit making the oceans rise.
In 1995, the International Panel on Climate Change issued a report which contained various projections of the sea level change by the year 2100. They estimate that the sea will rise 50 centimeters (20 inches) with the lowest estimates at 15 centimeters (6 inches) and the highest at 95 centimeters (37 inches). The rise will come from thermal expansion of the ocean and from melting glaciers and ice sheets. Twenty inches is no small amount—it could have a big effect on coastal cities, especially during storms. — Source.
In only a year and a half, the Spanish flu of 1918 killed as many as 90 million people around the world... that's more people in 20 months than AIDS has killed in 20 years.
Our modern understanding of hygiene has helped prevent similar catastrophes, but some viral outbreaks cannot be so easily navigated. Today's most dangerous virus is Marburg, originating from the same geographic "hot zone" as AIDS; with only a 0%-3% survival rate (no known patients have been discharged after having contracted Marburg) and no known cure, infectious disease scientists commonly refer to Marburg as a "slate wiper for humans". Most of us walk around ignorant of the dangers of a deadly flu outbreak, but Marburg scares the crap out of infectious disease scientists because their job is to be intimately familiar with this killer germ.
Marburg (pictured at left) is a hemorraghic fever, meaning it's a disease that "bleeds". Blood clots in the bloodstream clog small capillaries, which stop the blood supply to organs (including the brain), skin, intestines... basically, all affected parts of the body die prematurely, waiting only for the rest of the body to catch up. In the later stages of this virus, victims bleed from every orafice: mouth, gums, eyes, nose, ears, anus, vagina, fingertips. The virus attacks each cell of its host in an attempt to convert the host, cell by cell, into itself—this has the nasty effect of liquifying organs and turning the host's body into a walking time bomb of infection. By day three of exposure, one drop of blood may only have 200 viruses in it, but in only five days it will have duplicated its virus load to over five million. (A highly detailed account of Ebola's symptoms can be found here.) Since it is an Afrian tradition to physically care for cadavers after death, Marburg and other hemorhaggic fever cousins like Ebola Zaire and Ebola Sudan frequently decimate villages in that region.
Thankfully, Marburg and Ebola Zaire (pictured at left) can only be transmitted through blood and saliva and the virus is so "hot" that it burns up its victims before it can incubate and spread the virus far enough to do too much damage. Plainly put, as long as you stand back and wait, the poor infected victims will eventually die. The nightmare scenario nobody wants to think about is if Marburg or Ebola Zaire mutate into an airborne virus and does spread far enough that you don't realize how many people are incubating until it's already everywhere.
In 1989, 100 Macaque monkeys were illegally shipped to a warehouse is Virginia. Some of these monkeys were found dying of an unknown strain of hemorragic fever, the virus spreading quickly due to their cramped living conditions. No direct evidence showed humans could catch this particular strain of the hemorragic fever, but nobody dared risk it—all the monkeys were put down, their bodies incinerated. The warehouse was thoroughly disinfected with industrial strength bleach and extremely bright UV light to burn any remaining germs. While technically "clean", the warehouse remains vacant to this day. (You get the sense that authorities would have nuked the place if they could have.)
And then, a shocking discovery—after the warehouse had long been cleaned, it surfaced that a warehouse employee caring for the monkeys had caught a "cold" and vomited blood during a violent coughing fit... but a week later, he had completely recovered. Though highly coincidental, there was no certainty he had contracted the monkeys' virus. The awful truth is that nobody knew about this employee's cold until long after the monkeys had been cremated. Had this employee been incubating a deadly hemorraghic fever the whole time, who knows how far that virus could have travelled before authorities had stopped it? And if it had spread across the world, there wouldn't be enough bleach to disinfect such a wide area. A lot of people in the military and the CDC breathed a huge sigh of relief that day.
Our Next Monster in the Closet: Black Holes
Recommended reading: The Hot Zone: A Terrifying True Story by Richard Preston
Perhaps the most well known of all ELE's are massive comets crashing into Earth, like in Armageddon or Deep Impact. The most popular theory explaining dinosaur extinction is a 6 mile long (10 kilometer) comet smashing into the tip of the Yucatan peninsula, 580 miles due south of present-day New Orleans. Its impact was 2 million times larger than the most powerful man-made explosion ever created and left a 112 mile crater (180k).
But where do these big rocks come from? On researching ELE comets, I learned about a spherical group of ice chunks far far outside our solar system called the Oort cloud: 
Just as our planet has an orbit around our sun, our entire solar system (including our Oort Cloud) has an orbit within our Milky Way galaxy. More accurately, our solar system has two orbits: every 225 to 250 million years, it rotates around a semi-flat pancake of star systems we call the Milky Way galaxy. Our solar system goes round and round the Milky Way like a slow second hand on a clock, but every 28 to 30 million years it also orbits up and down, i.e., out of and into the thicker part of the Milky Way. In tandem, these two orbits make our solar system resemble a horse on a carousel oscillating up and down and round and round.
During one of these downward orbits into the dense thicket of the Milky Way's stars, our solar system increases its chances of coming close to stars, red dwarfs, black holes or anything else with significant gravitational pull. That could be a severe threat to us because any nearby gravity can distend the Oort Cloud and then—as the approaching star moves off again—its pull diminishes and launches comets out of our solar system's spherical Oort cloud shell towards the strongest source of our solar system's gravity—our sun... and thus to Earth.
Fortunately for us, Jupiter's massive gravity has repeatedly absorbed those comets; in fact, we even saw a set of these comets smash into Jupiter as recently as 1994: the Shoemaker-Levy comets.
I recently mentioned the Kardashev Scale and how it classifies our civilization as a Type 0.7, where a Type 1.0 civilization can harness the energy of an entire planet. Within my life, we've rocketed from a Type 0.67 to a Type 0.71 civilization and we'll likely exceed a Type 0.74 by the time I'm pushing up the daisies. Some scientists suggest we'll reach a full Type I civilization by 2200, followed by Type II by 5200, and finally a Type III by 7800.
Uh, what?
Okay, here's all that in kidspeak:
Type I = Harnessing a planet's energy = Kim Stanley Robinson's Mars trilogy (where Mars is terraformed)
Type II = Harnessing a solar system's energy = United Federation of Planets in Star Trek
Type III = Harnessing energy from multiple solar systems = The Galactic Republic in Star Wars
Type IV = Mastery of space-time itself = the Time Lords in Doctor Who or the Q Continuum in Star Trek
Most of these projections are (of course!) wildly hypothetical, but there must be some use—or comfort, at a bare minimum—in knowing where our children and grandchildren and great grandchildren are headed... even if it's off course by a few decades.
How does all this relate to extinction level events? Because over the course of Earth's history, several ELE's nearly signaled the complete termination of life on Earth... which would have obviously slammed the brakes on any civilization advancement at all. Most ELE's aren't one trick ponies, either—they're return customers, meaning we've got to cowboy up if we're going to survive—and thrive. So far, thanks to blind luck (or divine protection, if that's your preferred flavor), we keep bouncing back after these catastrophic close calls, even if it does take millions of years. The fact remains, though: any one of those ELE's could change that in a hurry.
So what are these ELE's, exactly?
Tomorrow, you'll meet the first terrifying monster in the closet—The Oort Cloud.
The research I'm doing for a writing project involves the scope and nature of extinction level events (also called E.L.E.'s). The truth of it is that much of my reading is simply too amazing not to share. The universe is such a crazy and dangerous place which can freak you out if you're the right brand of paranoid. You may get a little stressed out reading some of this stuff, but there is a huge glimmer of hope at the end of the tunnel... if you can stay the path.
There's too much to put it all in one place, so I'm going to break it up into a few easily digestible chunks:
