earth science
gregladen | January 25, 2009There are several things that can cause a magnetic signal to form in a rock (and this depends a lot on the rock). One is simply residing on a magnetic planet, like the earth. The other is being shocked by having, for instance, a meteor strike nearby. Another is heating from some other source. Many of the moon rocks collected by Apollo Astronauts show the second kind of magnetic signal (impact). This is not a surprise. But the presence of a signal caused by the first kind of magnetics would be especially interesting, because it would require that the moon have a self-generated magnetic…
grrlscientist | January 22, 2009tags: continental drift, geology, earth science, streaming video
This video shows how the continents have split apart and drifted around the globe. Further, it also shows their predicted movements in the future [1:20]
gregladen | January 17, 2009This is the seventh in a series of reposts from gregladen.com on global warming.
This installment is about sea level rise and fall, in the past. Sea level change that results from the formation and melting of glaciers not only has an enormous impact on the physical nature of the landscape, but it also would not have gone unnoticed by people living ever pretty far from the sea!
With large amounts of the world's water trapped in glaciers (mainly continental glaciers), the sea level drops. When that ice melts, the sea level rises.
As you know, the earth is covered by two kinds of surface:…
gregladen | January 16, 2009This is the fifth in a series of reposts from gregladen.com on global warming.
During the 1970s and 80s, creationists had a long list of reasons to doubt evolution, and every one of those reasons was wrong. But they had so many reasons, and it was so hard to keep track of them all, each with various versions, that a creationist that was trying to not live a lie could convince themselves that they had an honest dispute with evolutionary biology. But if you sat down and looked at every detail, "creation science" could be shown to be nothing more than a big bag of falsehoods. So to continue…
gregladen | January 15, 2009This is the fourth in a series of reposts from gregladen.com on global warming.
"Climate Studies" is a "causal" science. Most sciences are "causal" in nature, which is why the sciences and scientists are often loathed and distrusted by people in the humanities and some of the soft sciences. There is not the time or space right now to address this issue, but I'll just say this: People who criticize science for its interest in causality usually do not understand what scientists are talking about. I think this is partly because people in the humanities and social sciences have gone gaga…
gregladen | January 15, 2009This is the third in a series of reposts from gregladen.com on global warming.
Why It Matters What you Burn and When you Burn It
Carbon Dioxide is a deadly poison. It is about 50% heavier than air, so where it occurs in density, in mines or certain natural vents associated with volcanics, it can accumulate in low spots. There are places in the Western Rift Valley where puddles of Carbon Dioxide form overnight while the air is still. These gas puddles can occur over puddles of water. When animals (such as antelopes) put their head down to the water to drink, they take a few whiffs of the…
gregladen | January 14, 2009This is the second in a series of reposts from gregladen.com on global warming.
Why Greenhouses have nothing to do with the Greenhouse Effect, and more importantly, why CAN'T I microwave toast?
A greenhouse is a glass house that is sealed to keep air in and insulated to keep heat in but at the same time allow sunlight in. This sunlight contributes to the heat in the greenhouse by warming the ground or other material in the greenhouse, and of course the light energy is used by the plants. But the point of a greenhouse is to keep air that is warmed, by the sun and/or heaters that may be…
clock | January 13, 2009Did you know that the largest desert on Earth is Antarctica? And the second largest is Arctic? And only then comes Sahara!
Well, I knew that because Hal Heathwole taught a Desert Ecology course that many of my buddies in grad school took. But if you don't believe me, check out the Wikipedia page about deserts.
And then, don't stop at that. Do you have a blog? If not, start one. If yes, sit down and write a post about a desert. Then send it to the very first edition of the Carnival of the Arid:
Submissions should have something to do with a desert somewhere in the world. (If you're not…
gregladen | January 11, 2009One of the most interesting and exciting stories in science is that of the Younger Dryas. The Younger Dryas was a climate event that had important effects on human history, and that has been reasonably linked to some of our most important cultural changes, and ultimately some evolutionary changes as well. That is one reason why it is interesting. In addition, the Younger Dryas was a pretty big deal ... a climate change or something like a climate change that caused massive changes all around the earth, and fairly recently. But the cause of the Younger Dryas is at present unknown, although…
gregladen | January 11, 2009Just as unexpectedly as when the last swarm started, and just as unexpectedly as when the last swarm stopped, there is a new swarm. Verifying my initial statement: At least at some levels, the experts don't have much of a clue about these things. Not their fault. It's just that there is not that much data and there has not been enough study.
After a few days of relative quiet, a new earthquake storm has started up in Yellowstone Natioal Park.
According to the Island Park News:
A modest swarm of earthquakes began in the northeast corner of the Yellowstone Caldera Friday, the Yellowstone…
gregladen | January 6, 2009It turns out that a recently discovered population of land iguanas on the Galapagos is probably a new species that represents the basal (original) form of Galapagos land iguana. Moreover, this iguana is found in an unexpected place, according to a paper just coming out in the Proceedings of the National Academy of Sciences (PNAS).
And it's pink.
In 1984, Hickmann and Lipps said the following about the various pieces of evidence giving age estimates for the Galapagos islands:
... all are less than about 2 million years old. This age, together with independently determined geologic ages,…
gregladen | December 30, 2008... and other matters.
The following list represents widely held beliefs, either first order beliefs (things you hear people say) or second order beliefs (things implied directly by what people say):
Evolution is very slow.
It takes millions of years for a species to evolve into another species.
Evolution has stopped for humans.
Evolution occurs over "geological time scales."
Geological time scales are very long ... millions of years.
Geological and evolutionary time scales are similar to each other.
Evolution = Natural Selection.
"Macro evolution" is slow, "Micro evolution" is fast but…
gregladen | December 15, 2008Researchers in Nevada are reporting that waste coffee grounds can provide a cheap, abundant, and environmentally friendly source of biodiesel fuel for powering cars and trucks. ... [The authors] note that the major barrier to wider use of biodiesel fuel is lack of a low-cost, high quality source, or feedstock, for producing that new energy source. Spent coffee grounds contain between 11 and 20 percent oil by weight. That's about as much as traditional biodiesel feedstocks such as rapeseed, palm, and soybean oil.
details here
gregladen | October 1, 2008Welcome to the Third Edition of the Carnival of Evolution. The previous edition of this web log 'carnival of the vanities' was at Jason Rosenhouse's Evolution Blog. The next edition will be written by Mike (TUIBG) and hosted here, at Clashing Cultures.
Please submit your web posts on Evolution for the next carnival, which is slated for Mid October! Use this handy dandy submission form. And now, on with the show:
Newly reconstructed Neanderthal female. (View larger image) A Very Remote Period Indeed presents Fear and Loathing in the Pleistocene.
"... [the] narrator announces "Today,…
gregladen | September 29, 2008Fossils of a newly discovered species of dinosaur -- a 10-meter-long, elephant-weight predator -- were discovered in 1996 along the banks of Argentina's Rio Colorado, and are now being reported after a long period of careful study. This dinosaur dates to about 85 million years (which falls within the Cretaceous period).
Perhaps the most interesting feature of Aerosteon riocoloradensis is that it demonstrates the evolution of a bird-like respiratory system in an animal that is definitely not bird-like in most other ways. Indeed, the authors of this paper imply that this dinosaur's…
gregladen | September 12, 2008Life Science Teachers: Take special note!
This is not yet an error in the mainstream press, but there is an error afoot, currently represented in the widely read slashdot, which I imagine will propagate. The purpose of this post is to alert you to this problem and prepare you for the occasion when you run into a wackaloon creationist waving their arms around and screaming "Carbon dating does not work! It's been proven." This story also has a Global Warming Denialism component.
What I'm going to do here is give you the basic facts, then the misinterpreted text.
We start with the basic…
gregladen | September 1, 2008 Storm World: Hurricanes, Politics, and the Battle Over Global Warming I've been putting off posting my review of this book until just the right moment. Perhaps that moment is now, with the juxtaposition of a serious storm ... hurricane Gustav ... arriving in the vicinity of New Orleans and the opening day of the Republican National Convention, since both charismatic hurricanes and not so charismatic politicians play such a large role in the book at hand.
Storm World: Hurricanes, Politics, and the Battle Over Global Warming, by Chris Mooney, is a well written, informative, captivating,…
gregladen | August 29, 2008.... Or so goes the last sentence in the current National Hurricane Center forecast discussion.
This is Gusav. Even though it is only a strong tropical storm, it looks a lot like a hurricane already. This could be a Category IV hurricane in two or three days (Gustav, Atlantic Floater 1 Visible, Friday AM).
Right now, the level of complexity of Gustav's immediate future is higher than average for a hurricane. This is mainly because the two or three major atmospheric features that will determine Gustav's direction and rate of movement over then ext two days are themselves less predictable…
gregladen | July 29, 2008 An ugly fact killing a beautiful hypothesis I'm not mentioning any names, and don't ask me any details. In fact, don't repeat this story.
Some years ago, when I was a mere graduate student, a fellow student working in an unnamed country in Africa discovered a very very old stone artifact. To this day, this bit of chipped stone debris, representing the activities of an ancient very pre-human hominid, is one of the oldest well dated, in situ objects of its kind known.
The stone had some yeck on it, and for giggles, this stone got passed on to a physicist who had invented a new way of…
gregladen | July 29, 2008Did Past Climate Changes Promote Speciation in the Amazon?
Any time you've got a whopping big river like the Amazon (or a mountain chain like the Andes, or an ocean, or whatever), you've gotta figure that it will be a biogeographical barrier. Depending on the kind of organisms, big rivers, high mountains, oceans, forests, deserts, and so on can provide a habitat or a barrier, and when there is a barrier, populations may end up splitting across that barrier and diverging to become novel species.
The role of the big tropical rivers such as the Amazon and the Congo, and the role of rain…