Discovery News: Strike Slip

Awesome Video of Greenland Glacier Disintegrating

Following on the story earlier today about glacial earthquakes, you totally need to check out Jason Amundson's videos of Jakobshavn glacier breaking up in June of last year. The ice breaking up in these vids is so huge and so heavy that as it rotates (center of the picture) and begins drifting out to sea, it literally makes the earth shake to the tune of a magnitude 5.0 (or so) earthquake.

The sound you hear is the actual sound the berg made as it scraped over the fjord bottom -- Amundson sped up the seismic recording 25 times to make it audible.

Several kilometers of ice shearing off the Greenland ice sheet is always awesome to behold, and the few thousand folks living down-fjord of Jakobshavn agree; ice-induced tsunamis regularly crash ashore in Ilulissat Harbor, 50 kilometers away from the glacier's edge. A phenomenon they've dubbed 'kaneling.'

Rest assured, though, these waves are usually just 1/2 meter high or less when they arrive in the harbor, and they're mostly harmless...mostly.

This is a slightly more dangerous version of an ice-tsunami. And yes, that there at the end of the video, that's a couple of guys in a little boat fleeing for their lives:

Sources: Jason Amundson, University of Alaska, Fairbanks and Ilulissat Kommuneat

A Small Brick in the Wall

It's a start. The city of Chicago is pledging to reduce greenhouse gas emissions by 25 percent below 1990 levels by 2020. Mayor Richard Daley has authorized retrofitting of low-income housing for energy efficiency, retooling of building codes, and large installations of solar panels on public property.

This is good. Very good. But perhaps the most impressive thing is that the Union of Concerned Scientists called it the most quantitative and robust plan for reducing greenhouse emissions in any US city.

I generally trust UCS to do thorough research and planning on whatever they projects they undertake, so I'm pretty excited about this.

Look, I know California has promised huge cuts in emissions by 2050, and I think they (we, I live there) can get there. But Apart from CA's low-carbon fuel plan, I haven't seen any detailed work towards this goal yet. Other states have similar plans, but as far as I know -- and please correct me if I'm wrong -- they're equally nebulous right now.

And 2020 ain't far off. In five years Chicago should be able to show major signs of achievement.

This is pretty encouraging  -- let's just keeping checking in to make sure the politicians stick to the program.

(image: www.isbor.org)

Why Tropical Storm Gustav Could be a big Problem

Eric "SciGuy" Berger over at the Houston Chronicle is really good at keeping up with the latest in tropical storm and hurricane activity in the Gulf of Mexico. I think I would be too if I lived in Houston, a city itching to have its clock cleaned by a big storm raging out of the Gulf.

His latest post on TS Gustav is really interesting, highlighting the volatility that results whenever a tropical cyclone finds its way into the Gulf of Mexico.

The cause for concern is, briefly: when a storm passes over a particularly warm stretch of the Gulf, it can spin up in a big hurry, going from Category 1 to a 5 in the course of a day or two.

This was exactly what happened with Katrina, and then again with Rita, both in 2005. The storms passed over warm eddies of the Gulf Stream called the "Loop Current," and as Berger points out, a couple of oxbow-shaped loops are currently hanging around:

It's no guarantee that Gustav will find a loop current and get really evil in the coming days. Hurricanes are highly unpredictable, and as Berger mentions, Gulf temperatures are down from what they were when Katrina and Rita visited its waters in 2005.

Then again, there's no guarantee it won't, either. An infant Katrina wandered aimlessly in the Bahamas, much like Gustav is right now near Haiti.

Image: Naval Oceanographic office, via SciGuy

Alvin's Awesome Successor ROV

In Monday's New York Times, William Broad penned a great, behind-the-scenes illustration of the new deep-sea submersible being built to succeed the Alvin Remotely-Operated vehicle (ROV).

The original Alvin will be leaving some big shoes to fill -- he was the first to dive on the Titanic, and opened our eyes to the mysteries of the black smokers; hydrothermal vents hiding deep in the oceans that scientists now think may have been the home of the first life on Earth.

Apart from the story's lead -- forging a huge sphere of near-molten titanium -- there are couple of other major technical hurdles to overcome before the new Alvin will come to life.

But I've got faith that these ocean engineers can come through. I spent six weeks on board a research vessel in the North Atlantic back in 2002 and for my money, no one combines a love of research with a lust for heavy machinery like an oceanographer.

Image: San Diego State University, via NOAA

Bye Bye, Sea Ice

It's that time of year again -- the time when ice researchers gather round the latest satellite data from the Arctic, and probably drown their sorrows in a stiff drink or three.

Last year was major cause for alarm -- sea ice coverage was at its lowest ever in the summer of 2007. That pushed up a lot of projections for an ice-free Arctic from 2050 or so to as soon as ten years from now.

"But there's a lot of variability in the climate system, and it's possible 2007 was an anomaly" some might say. True enough, but things are looking bleak again this year -- the latest data are in, and 2008 just past 2005 for the second-smallest ice coverage on record. Bummer.

According to the latest from the National Snow and Ice Data Center, the sea ice extent was down to 5.26 million square kilometers (2.03 million sq miles) as of yesterday, August 26.

That's down 2.06 million sq kilometers (795,000 sq miles) since the beginning of the month, but it's not the worrying bit. The worrying bit is that the ice is probably not done melting yet. In 2005 the ice minimum didn't occur until September 21. As you can see from the graph below, it's pretty typical for sea ice to take until then to start refreezing.

This preliminary measurement is missing one key piece of context, though -- how much of the ice being lost is perennial sea ice? Ice that makes it through the summer without melting is thicker and shows up differently on satellite images, so researchers should be able to figure out how much was lost compared to last year.

Of course since 2007 was the worst year ever (unless the ice melts another 430,000 sq kilometers in the next month) it's possible that this year will register something of a gain in perennial ice.

If there is, it won't make headlines because the gain won't be big or very meaningful. The individual years don't matter so much -- it's really the trend that they describe that we should care about. Looking at the NSIDC's graph I think it's plain: an ice-free Arctic Ocean is on its way. It's just a matter of time, and not much, either.

Note: in case it's hard to read the graph, the black line at the top is the 1979-200 average sea ice extent. Gray is 2005, green dashed is 2007, and the bright blue is 2008.

Images: National Snow and Ice Data Center

Earthquakes are a'comin...to New York

The citizens of Gotham probably don't spend a lot of time worrying about earthquakes. And why should they? The last time even a magnitude 5 quake -- a moderate shake, like the one that struck south of Los Angeles last month -- was 1884.

But new research from seismologists at Columbia University's Lamont-Doherty Earth Observatory should put the New York metro area on notice: the network of faults beneath New Yorkers' feet has the potential to break off a magnitude 6 or 7 quake. From the LDEO press release:

Based on the lengths of the faults, the detected tremors, and calculations of how stresses build in the crust, the researchers say that magnitude 6 quakes, or even 7—respectively 10 and 100 times bigger than magnitude 5--are quite possible on the active faults they describe. They calculate that magnitude 6 quakes take place in the area about every 670 years, and sevens, every 3,400 years. The corresponding probabilities of occurrence in any 50-year period would be 7% and 1.5%.

After less specific hints of these possibilities appeared in previous research, a 2003 analysis by The New York City Area Consortium for Earthquake Loss Mitigation put the cost of quakes this size in the metro New York area at $39 billion to $197 billion.

Come again? Was that $197 billion dollars? Depending on how you tally up economic impact, Hurricane Katrina cost somewhere between $81 billion and $150 billion. Pretty steep, but then that's the bill for the total destruction of a major city in America.

So it should come as little surprise that flattening New York -- as unprepared for an earthquake as New Orleans was for Katrina, maybe even more so -- would be even more expensive. Lamont's Leonardo Seeber put it best:

"We need to step backward from the simple old model, where you worry about one large, obvious fault, like they do in California," said coauthor Seeber. "The problem here comes from many subtle faults. We now see there is earthquake activity on them. Each one is small, but when you add them up, they are probably more dangerous than we thought. We need to take a very close look." Seeber says that because the faults are mostly invisible at the surface and move infrequently, a big quake could easily hit one not yet identified. "The probability is not zero, and the damage could be great," he said. "It could be like something out of a Greek myth."

Seeber's comment is a little unnerving. As you'll see in the image at right, the group's data from the last  34 years shows a bunch of smallish earthquakes clustered in a Northeast/Southwest trending line north of the city called the Ramapo Seismic Zone.

Incidentally, that line runs within about 2 miles of the Indian Point nuclear power plants. Last fall the Lamont researchers sent their still-unpublished data to the New York attorney general, warning that a powerful quake could seriously damage the plants.

But Seeber's saying that fault may be the least of our worries. A number of poorly-understood faults lie in a series of parallel lines to the south and east of the big fault. Nobody knows much about how big they are, or when they were last active. One of these, the ominously-named 125th Street fault in upper Manhattan may have been the site of a magnitude 5 or so temblor that shook the island.

Back then the area was largely uninhabited. When the next one hits, millions of New Yorkers are going to have really bad days.

Images: CA Dept. of Conservation, Columbia University via EurekAlert

The Astrobiology Rap

I love hip hop. I love science. And I *love* this little piece of sci-rap from emcee Oort Kuiper (aka Jonathan Chase), extolling the many, many virtues of astrobiology. Here it is on YouTube, and it's part of the Summer 2008 issue of Astrobiology Magazine European Edition.

Starting off with a famous of all computerized voices, Stephen Hawking, and moving in to discussions of the origins of life on our planet, and the search for it elsewhere, Kuiper's not a half-bad emcee. His choice to splice in a snippet of Carl Sagan's narration from "The Cosmos" series is a classic touch, too.

Admittedly, it's not as incendiary, hilarious, or well-produced as the Richard Dawkins Rap, which lambasted evolutionary biologists for not not accepting the religiously-motivated Intelligent Design movement's attempts at corrupting science.

Not surprisingly, that video was put together by the producers of the pro Intelligent Design movie "Expelled." You know, the one with Ben Stein straining to make the ugly case that modern science is equivalent to Nazism in its strident rejection of outside opinion? Oh, you mean you have you seen it? Good, don't bother -- it sucks, even apart from it's dogmatism, it's just a poorly made film.

I'll admit, the cash that must've been spent on the Dawkins Rap made for a good YouTube flick -- I mean "Dick-to-the-Dawk, to-the-PhD. He's smarter than you, he's got a science degree" -- that's pretty catchy. And "Astrobiology 2008 -- Infotainment" probably won't get millions of views on YouTube, and its production values don't measure up to the Dick-to-the-Dawk.

But in terms of earnest, good ideas about how to communicate science to the masses, Oort Kuiper is onto something. If he keeps at it, I could see him one day rising to the all-time high bar of educational videos -- Schoolhouse Rock's Conjuction Junction.

Image: Schoolhouse Rock

Early Humans v. Climate Change -- Who is the Greater Destroyer?

Around about the time the last Ice Age was ending on Earth, a number of extinctions occurred. Most notably the Woolly Mammoth, which had been thriving for tens of thousands of years, met its end around 4 thousand years ago.

Traditional thinking has been that the great beasts died out as the planet's climate warmed dramatically with a long period of thawing that started around 20,000 years ago. Adapted to millennia of cold, the animals simply weren't able to handle the climate change, and so they died out.

But recently scientists have begun to suggest that humans, with their big brains and hunting spears may have collaborated with climate change to hunt the Mammoth into extinction.

So who is the greatest killer of all?

New evidence is adding to the pile that humans win the prize for worst killers, at least for the last 10,000 years. Sure climate change played a role in thinning out the mammoths, but researchers are now reporting that humans probably killed off the Giant Kangaroo, Marsupial Rhino, and a host of other big animals (aka 'megafauna') that had been happily living in Tasmania until we showed up.

There's plenty of other evidence that humans are efficient murderers, and some people have argued that the planet has been so altered by our presence that the last 200+ years constitutes a new geologic period called the Anthropocene. Even worse, there's debate over whether the extinctions that began with the end of the Ice Age ever ended, or whether humans just took over where climate change left off.

Call it one big, 10,000 year-long extinction that's still going on today.

OK, so humans appear to be the clear winners in this morbid contest, right? Not so fast. As I mentioned last year in an article for New Scientist, non-anthropogenic climate change is now thought to be the cause of perhaps *every* one of the so-called Big Five mass extinctions in Earth's past. Yes, including the one that killed the dinosaurs 65 million years ago.

We homo sapiens have already shown ourselves to be prolific killers using nothing more than sharpened stones. The fact that modern society has stumbled on the greatest destructive power the planet has ever known -- climate change -- should make us very worried indeed.

Image: NASA, via UC Irvine

Getting a Piece of the Arctic Pie

Everyone's heard of the Wild West -- get ready for the Wild North. As sea ice in the Arctic keeps melting, the region is going to become one of the last great frontiers of oil, gas, and mineral exploration on the planet.

Trouble is, the United States, Canada, Russia, and several countries in Scandinavia all have major claims to the region. For the most part the boundaries have been drawn, but there are a few areas of overlap, and they could lead to a good, old-fashioned international territorial dispute.

To try and help sort things out, researchers at Durham University in the UK have put together a map of countries' claims and where they overlap.

As the scientists point out, a lot of the problem stems from the fact that the Arctic Ocean is essentially uncharted. Every country gets exclusive rights to the 200 nautical miles of water off its coast. The rule designed to cover the continental shelf, a relatively shallow part of the sea floor that is often rich in resources.

But no one knows for sure where the continental shelf ends in the Arctic Ocean. Research expeditions from the interested countries are trying to figure this out, but it's likely that everyone's going to have a different definition of where their piece of shelf ends, allowing them to draw territorial boundaries that benefit them the most.

Should be an interesting kettle of fish to keep an eye on as the amount of open water in the Arctic keeps increasing.

Source: Durham University

The Awesomest Map on (and of) Earth

What would the planet look like if you didn't care about political borders attention to country borders, trees, soil, or even water? Why, it would look just like the image at your left -- a geological map of the world.

Generally speaking, geologists are obsessed with maps. From the cheap gas station variety to 1:24,000 scale "quad" maps that most rock jocks use to find their way in the field, they can't get enough.

But our fascination with maps goes beyond geo-geekery. Maps provide a unique way of looking at the world; a new perspective on the state, region, country, and planet we live in. Witness the popularity of a site like Worldmapper, which lets you distort countries' sizes based on their GDP, population size, or oil consumption rates. Or Google maps, whose Street View function lets you peer into strangers' bedroom windows in several cities around the world.

The have been gobs of technologies operating out of the public eye for a long time that have led to these explosion of popular widgets. Constellations of GPS satellites have been letting us (or at least our military) know exactly where we are on the globe for decades, while geographers have used GIS (that's Geographical Information Systems) for everything from mapping the effects of climate change on glaciers to charting urban sprawl and air pollution to finding unexploded bombs in the Iraqi desert -- during the *first* Gulf War.

So a new tech called OneGeology could be seen as just the latest addition to the heap of mapping awesomeness. But it's more than that, it's any geologists' wet dream: a comprehensive geological map of the world (pictured). Equal parts GIS, Google Earth, and bedrock map, OneGeology promises to provide a whole new venue for geologists to maniuplate mapping data. It should lead to lots of amazing new science, but at the very least, as this video on YouTube shows, it'll give us a pretty stunning new way of looking at our humble planet.