Courtesy FundyAlong with wind and solar, harvesting power from tidal forces comes up a lot in discussions of alternative energy sources.
Was that a horrible sentence? I think it was. What I meant to say is this: we can generate electricity from tides, and lots of it. "Tidal power" is often brought up alongside solar power and wind power, but while I can easily picture windmills and solar panels, I'm not always sure what sort of device we'd use to harness the power in the tides.
This sort of device! For those of you too afraid to click on a strange link (who knows... I could be linking to an image like this!), the article depicts something that looks sort of like a thick, stubby windmill, with blades on its front and back. It's a tidal turbine, and at 74 feet tall and 130 tons it's the world's largest. It should be able to supply electricity to about 1,000 households. Pretty impressive.
Tidal turbines, apparently, are so productive because water is so much denser than water, and so it takes a lot more energy to move it. An ocean current moving at 5 knots (that's a little shy of 6 miles per hour, for the landlubbers) has more kinetic energy, for example, than wind moving at over 217 miles per hour.
At least according to that article, the United States and Great Britain each have enough tidal resources (areas where this kind of generator could be installed) to supply about 15% of their energy needs.
More info on the tidal turbine, which I am calling "the Kraken," because it's big, underwater, and will occupy your mind for only a very short time.
Courtesy Public domainA massive chunk of ice - 100 square miles of it – broke away from Greenland’s Petermann Glacier last week. The ice island is about 500 feet thick and contains enough fresh water to supply our entire nation’s tap water demands for 4 months and then some.
Just what the free-floating slab of ice will do next is anyone’s guess. Some scientist, such as Andreas Muenchow, a professor of ocean science and engineering at the University of Delaware are concerned it could get wedged in by actual islands dotting the Nares Strait between Greenland and Canada and jam up shipping lanes there.
"The newly born ice island may become land-fast, block the channel, or it may break into smaller pieces as it is propelled south by the prevailing ocean currents,” Muenchow said. “From there, it will likely follow along the coasts of Baffin Island and Labrador, to reach the Atlantic within the next two years."
A similar, huge slab of ice broke away from Greenland’s Ward Hunt Ice Shelf in 1962, and pieces of it became stuck in channel islands in the Nares Strait which is located about 600 miles south of the North Pole.
Muenchow has been keeping a watchful eye on the Petermann Glacier for the past several years and said he was expecting a calving to take place because the ice shelf had been growing. However, he wasn’t expecting one so large.
Although recent trends show a rise in global temperatures, Muenchow stops short of blaming the ice slab on climate change. "Nobody can claim this was caused by global warming. On the other hand nobody can claim that it wasn't," he said.
The Petermann Glacier is an ice shelf situated in northern Greenland covering an area of about 40 miles. The new ice island amounts to about twenty-five percent of the ice sheet. The following video from last summer shows why scientists were expecting last week’s event.
Courtesy Mark RyanA recent study published in the journal Palaios raises new questions about the role of bacteria in the process of fossilization of bone material. In tests simulating rapid burial and groundwater percolation, researchers Joseph Daniel and Karen Chin set up four different groundwater environments where chunks of bone were placed in river sand and water, laden with calcium carbonate, was allowed to flow through it for three months. In one test the environment was left untreated allowing for bacteria in the sediment to grow naturally. In two other tests the simulated environment was sterilized using antiseptics that either reduced or eliminated completely the naturally growing bacteria. For the fourth test, Chin and Daniel washed and treated the sediment with bleach then reseeded it with the natural bacteria.
The samples were monitored closely, and after just one week, the scientists noticed mineral precipitants had already begun to attach sand grains to the bone fragments in both the nonsterile tests, but saw no change in the sterile environment samples.
After three months, the results showed that the cubes of bone soaked in the natural, untreated environment had begun to show signs of permineralization, and some of the bacteria even showed early signs of lithification. As before, the fragments in the sterile environment were unchanged and appeared as fresh as new bone.
This is pretty amazing, because I was always under the impression that in order to become a fossil, the remains of an animal had to be buried rather quickly so as to remove them from the destructive elements of nature. But it looks like some of nature’s tiniest elements are necessary to the process.
This study could also help explain how, after 68 million years, organic material managed to remain essentially unchanged (or actually less-permineralized) deep inside the fossilized femur of a Tyrannosaurus rex, such as that discovered a few years back by paleontologist Mary Schweitzer (Read about it here).
Karen Chin, by the way, specializes in the study of fossil feces (coprolites), and participated in a 2001 study also published in Palaios documenting the role of bacteria in the fossilization of herbivore dinosaur droppings.
Courtesy ASPEX Corporation
Courtesy ASPEX CorporationLast December Joe made a post about a company that offered to provide free scanning electron microscope images (in this case a backscatter scanning electron microscope or BSEM) of whatever people sent in (within reason I suppose). I took the ASPEX Corporation up on its offer and mailed in some of the clay I had collected from the K-Pg boundary I visited last spring in southern Colorado. The K-Pg boundary, as most of you should know by now, marks the end of the Cretaceous period and the beginning of the Paleogene period. It used to be called the K-T boundary for Cretaceous-Tertiary but the term “Tertiary” has fallen into disfavor. Anyway, some 65 million years ago something wiped out all the non-avian dinosaurs, and left a tidy 1-inch layer of iridium-rich clay in several locations worldwide for geologists to puzzle over. Iridium is a rare-earth element (atomic number 77) but is fairly common in asteroids, meteorites, and other such extra-terrestrial space objects, so eventually, scientists came to the conclusion that such high amounts of iridium had to be from an extraterrestrial impact, and sure enough, an impact crater just the right size and age was eventually uncovered off the Yucatan Peninsula near Chicxulub, Mexico. (There’s been many years of discussion about the cause of the dinosaurs’ demise but just last month a committee of highly scientific mucky-mucks officially declared that the Chicxulub asteroid was the guilty culprit.)
Courtesy ASPEX Corporation
Courtesy ASPEX CorporationIn Colorado, I found evidence of the Chicxulub impact about 10 miles west of Trinidad, Colorado. The outcrop at the Madrid East site on the way to Long Canyon is probably one of the better-defined exposures of the K-Pg boundary and is easily accessible off the main highway. A distinctive 1-inch layer of ashen gray clay can be seen sandwiched between two layers of coal – a 2-inch layer above and a 16 inch layer below - and the sequence is capped by massive Paleogene sandstone. While there, I scraped out a sample of the whitish clay to bring home.
Anyway, when Joe mentioned the free SEM scan I sent ASPEX some of the clay I’d collected hoping the scan might reveal some evidence of high iridium content, and of shocked quartz and glass spherules, telltale signs of an impact. Once sent, I promptly forgot about it until recently when a reply showed up in my mailbox.
Courtesy Mark RyanThe results weren’t quite what I was hoping to see, but I did learn something. The images sent back don’t show much – at least not in the way of iridium, shocked quartz, etc. But the chemical analysis shows the clay layer (yellow arrow in photo) is indeed mostly just that - clay, or more specifically aluminum silicate hydroxide better known as kaolinite (it also contained some titanium, potassium, and iron). Kaolinitic clay is thought to result from the altering of volcanic ash beds in acidic coal swamps, but in this case it’s the result of a doomsday shroud of impact material interacting with a coal swamp. The kaolinite is the one-inch white stripe in the photo and is the layer I sampled. Unfortunately, the analysis from ASPEX shows no signs of an iridium anomaly, and here’s why:
The iridium I’ve since learned isn’t actually concentrated in the clay layer itself but in the 2 layers directly above it (red arrows in photo): that is the impact layer (smectite - blue arrow in photo), and the 2-inch coal layer directly above that. I was under the incorrect assumption the iridium was in the clay layer itself since that layer is what seems to mark the K-Pg boundary at least in the Raton Basin in southern Colorado.
My problem is I’m only an amateur geologist so I tend to operate on limited knowledge. Once the results of the scan showed up, I did do some further research and discovered much more information than I had when I visited the site last year. I was at the right place and was able to identify the boundary layer, I just didn’t have all the facts. But at least I’ve learned something from my mistake, so it turns out not to be such a bad thing. And now you’ve learned something, too.
ASPEX Send Us Your Sample page (I’m not sure they’re still doing it)
More about the K-Pg extinction impact
USGS K-Pg in the Raton Basin info site
Universe Today K-Pg boundary info
Buzz post on dinosaur extinction
Courtesy obiwanjrYou know, when that oil rig went down and started spilling hundreds of thousands of gallons of crude oil into the Gulf of Mexico, I thought, “What a downer. My reruns of ‘Yes, Dear’ are going to be interrupted with news footage of crying beavers and stuff for months now.”
But then BP came up with that idea for the containment dome, and I thought, “This is so crazy… it just might work. This could be more entertaining than ‘Yes, Dear.’ If such a thing is possible.”
But, no. The dome failed. Petrochemicals and near-freezing ocean water combined to form crystals in the dome, and it didn’t work. And it was super far underwater, so the failure couldn’t even be set to Benny Hill music or anything. Not entertaining.
I was just resigning myself to the fact that such a horrible accident might not actually be funny, when the jokers at BP let slip that they might have another hilarious trick or two up their sleeves. The dome didn’t work? Let’s try a giant “top hat”!
Yes, BP will be sinking a giant top hat onto the leaking oil pipe. It’s not really a top hat, of course; it’s actually a smaller version of Friday’s giant failure. I’m guessing it’s a sort of a bonus joke. But BP claims that the smaller contraption should have better chance of success, except that even if it does work, it won’t work as well as the dome was supposed to. (The dome was supposed to capture something like 85% of the leaking oil. But it captured 0%, so that’s sort of academic. Or, again, a bonus joke.)
And BP even has another plan, a Plan C, if you will, in the works, in case this one flops. Sort of how they filmed the second and third Matrix movies at the same time. According to my sources, the discussion behind plan C went sort of like this:
“So… what does everyone hate?”
“Yes, for sure Nazis. What else?”
“Um… oil spills?”
“Correct! Oil spills.”
“Ooh! We should do one of those!”
“No, people hate them. Plus we already have one. So what does everyone like?”
“Top hats, obviously. So we should throw one of them in the mix. But, if someone doesn’t like top hats, what do they probably like?”
“Everybody likes… ball pits?”
“Ball pits! Exactly! Let’s do something like that!”
“And tires! Old tires!”
“Yes, old tires too!”
So, in case the top hat doesn’t work, BP is considering injecting the leaking system with golf balls. And old tires. And then they would cap it off with some cement. Oh, right, and there’s this part too:
“What should we call it?
“A ‘junk shot.’ Duh.”
“Oh, my God. Totes perfect.”
And then, I assume, everybody else in the room had to go wash their ears out after hearing the unfortunate term “junk shot.”
Others have warned that such a “junk shot” could have repercussions beyond the phrase appearing in print: damaging the huge valve system at the base of the well could result in oil leaking out even faster—as much as 12 times the current rate.
Performing a junk shot against the flow of oil and the under the pressure at that depth will be extremely challenging, too. According to an expert from Tulane University, such an operation would have to cope with 2,200 pounds per square inch of upward pressure, which would make pumping golf balls and tires down very tricky.
However it turns out, it’s sure to be a barrel of laughs. Or oil. Thousands and thousands of barrels of spilled oil.
(I don’t have any better ideas, by the way. Except not to have a leaking pipeline a mile underwater. But you know what they say about hindsight.)
Courtesy 3aodiaThe largest study ever of tornadoes is now underway in the central plains of the United States. Named Vortex2, the study will involve over 100 storm chasers from several countries and a fleet of movable weather equipment, including mobile weather stations, radar, and balloon launch platforms. Forty well-equipped vehicles will be crisscrossing the back roads of the Midwest throughout Tornado Alley, the area stretching between West Texas and southwestern Minnesota. Their mission is to closely track developing storms and find and gather information about tornadoes, one of Nature’s most destructive weather forces. (Last week’s devastating tornado in Yazoo City, Mississippi tore a path 1.75 mile wide and stayed on the ground for nearly 150 miles).
This is actually phase two of the study. Phase one began in the spring of 2009 which, unfortunately for the researchers, was an historically low period for tornadoes. There was one bright spot last year in Wyoming, where the storm chasers were well prepared and made what was probably the most thorough study of a tornado in history.
The original Vortex project took place in 1994-95 with a follow-up four years later called Vortex-99. But Roger Wakimoto, director of the Earth Observing Laboratory at the National Center for Atmospheric Research, said those studies raised more questioned than they answered.
"We are still struggling to find out what actually triggers tornado generation," he said. "It's very difficult to get detailed data. These things are very transient."
Maybe this year things will be different, and questions about the how, why, when, and where of tornadoes will get answered. One interesting hypothesis the Vortex2 team hopes to settle is the one that claims tornadoes may actually start on the ground and reach up to the clouds, countering the popular notion that twisters descend from the sky. Support for this theory includes eyewitness reports of ground damage occurring prior to a funnel cloud’s arrival, and the fact that similar but less destructive phenomenon like dust devils and waterspout do just that, start on the ground and rise up into the sky.
Of course, there are plenty of other questions about the nature of tornadoes to answer, and the storm chasers hope to do so. But I have a feeling - with the Vortex2 team - the fun is all in the chase anyway.
Vortex story at Forbes.com
More about Vortex2 on the Weather Channel website
Videos about Vortex2 at Worldnews.com (The tornado in a soap bubble video is great!)
Brief overview of tornadoes by George Pararas-Carayannis
Courtesy uscgd8 The costs of a "Drill, Baby, Drill" policy are being measured this week in lives, money, business income, and environmental damage.
BP (British Petroleum) says it is spending $6 million a day to battle a growing oil spill which resulted from a deep water oil rig accident. The oil rig, Deepwater Horizon, worth $560 million, was destroyed. Eleven missing workers are presumed dead. Crude oil continues to flow into the Gulf at about 5000 barrels (210,000 gallons) a day. Fishing and tourism businesses are fearful upon hearing that the oil spill is only a day away.
Please use our comments feature for news updates, ideas, or opinions.
Physicist Neil deGrasse Tyson said,
"If you're scientifically literate, the world looks very different to you. And that understanding empowers you."
(You can hear Mr. Tyson "sing" this line in the Symphony of Science/Poetry of Reality video below.)
Courtesy United Nations Development Programme
I've been thinking about that idea a lot today after hearing two stories:
The cause of the Haitian earthquake is clear--100% explainable without having to invoke pacts with the Devil or martyr's ghosts. Same in Iran -- geologic activity in the area will continue whether or not women are veiled and chaste.
The solution is not "to take refuge in religion." The wrangling over unverifiable, supernatural causes for things diverts very needed resources and attention from real world solutions to very urgent problems.
The solution is to take refuge in science. Michael Shermer (yup, he "sings") says,
"Science is the best tool ever devised for understanding how the world works."
The Earth hasn't changed. People have. We're seeing quake activity with big consequences because there are more of us than ever before, many, many of us live in developing countries where large populations live in dense communities with lax building codes, and communications technology means that we know what has happened, not because we're paying a geological price for not living our lives correctly.
So what do we do? We innovate. We devise new and better monitoring and warning systems. We develop building techniques that are both locally appropriate and safer in the event of a quake. We teach people how to protect themselves in an emergency and how to react afterwards.
Richard Dawkins (my current nerd crush; you can watch him "sing" in the video, too.) said,
"Science replaces private prejudice with publicly verifiable evidence."
How can you not get behind an idea like that?
Courtesy Mark RyanAs Thor posted below, there’s been a whole lot of geological activity going on around the world lately what with all the large earthquakes and the volcano in Iceland spewing hot ash into the friendly skies. Luckily, Minnesota is situated on the very stable and essentially cold and dead North American craton. Devastating earthquakes and volcanoes are in our distant past, but that doesn't mean we don't get our share of geological action. Just last weekend I stumbled across evidence of a recent catastrophic event in one of St. Paul's parks.
I was out fossil hunting, scouring the sedimentary layers on the east banks of the Mississippi River. The strata there are the well-known record of the deposits of the Ordovician seas that once covered this part of Minnesota some 450 million years ago.
Courtesy Mark RyanIn the Twin Cities area, the base of the rock sequence is comprised of St. Peter sandstone, a soft and easily eroded rock that grades into a very thin layer of equally soft Glenwood shale. Immediately above those soft layers is the much more resistant Platteville limestone. The sandstone base has a habit of eroding away in the elements, often leaving a limestone overhang. Sooner or later, gravity wins out and the Platteville shelf collapses. This is what apparently happened in Hidden Falls Park in St. Paul recently. A whole lot of the limestone came crashing down, taking out some good-sized trees and blocking entry into the park. This gradual (and sometimes catastrophic) natural process has been going on for tens of thousands of years, ever since the glaciers exposed the layers. Usually, on our puny human timescale, it goes unnoticed. But it’s all part of the on-going rock cycle. Our famous Minnehaha Falls and its present location are the result of this relentless erosion process. As is St. Anthony Falls near downtown Minneapolis, which used to be located much farther down river from where it is today. In the process, the sandstone gets broken down into sand again, and the limestone blocks are eventually reduced to rubble. All of it will someday end up in the Gulf of Mexico unless some other forces intervene.
Courtesy Mark RyanI said earlier the scope of the rock slide impressed me, but maybe "unnerved" is a better word. I often scale the river bluffs looking for fossils, and I sure wouldn't want to be underneath something like this when the forces of nature decide to have it collapse. Across the river at Lilydale Regional Park there was an unfortunate incident several years ago when an overhanging shelf of limestone (in this case the Cummingsville member) fell and killed a fossil hunter. Luckily, no one was injured in the Hidden Falls event (at least as far as I know) but as you can see in the photos, there’s still quite a lot of the Platteville still up there, jutting out, and ready to come down at anytime. I wonder if the city of St. Paul plans to help it along? Whatever the case be careful when exploring along the river bluffs.
Moving water is an extremely powerful and earth-shaping force of nature. It can also be quite lethal. According to NOAA, over a 30-year average (1979-2008) flash floods have killed more people than any other weather-related natural disaster in the US. With that in mind, here are two remarkable video clips of flash floods that came to my attention via Rebecca Hunt-Foster’s Dinochick Blog. The videos were shot by David Rankin of Rankinstudio.com who keeps close watch on the local weather in southern Utah, and whenever heavy rains occur, runs out with camera in hand to capture the amazing power and erosion of the resultant flash floods, that drag along everything that gets in their way. This explanation of the phenomenon and why it interests him is from his website:
“1 inch of rain over 1 square mile amounts to over 17.38 million gallons of water that need to be drained. Some of the floods in these videos were produced when 2 - 4 inches of rain fell over 30 - 60 square miles, over a few billion gallons of water draining down one wash in the desert. These washes are usually bone dry for most of the year until the monsoon rains come. They can turn into raging torrents within minutes and are very dangerous during this time of year. If there hasn't been much local heavy downpour the floods come through looking like a tsunami with a wall of water that can get up to 5 feet high, and tear up everything in its way. This is what you see happening in these videos. I am also interested in raising awareness when it comes to these beasts. They are quite dangerous, and can come through up to 6 hours after the storms that create them pass by with almost no warning.” – David Rankin