Global Warming May Have Killed the Dinosaurs 269
The Fun Guy sent in a link to the American Society for Microbiology site, your leading news source for everything between nano and macro. The site is featuring a story about new research into the KT barrier extinction: the period in history where the dinosaurs went extinct, along with a number of other families of species. For a number of years scientists have theorized that an impact on the Yucatan peninsula was responsible for the species crash, but microbiological examination of marine organisms of the time indicate life persisted for another 300,000 years after the 'Chicxulub impact'. The researchers at Princeton who made this discovery theorize that global warming caused by a volcanic eruption in India is a more likely culprit for the world-wide devastation. The article generalizes that there is no 'smoking gun' for this event, and further research is required.
Oh really? (Score:3, Interesting)
So Global Warming looks like a comet? Good thing McNaught isn't going to hit us, eh?
It's sad that there's a massive following of climate change deniers online, but such is the nature of the Internet - even the kooks have large communities that can email millions of people.
Global warming ... just not that way. (Score:5, Interesting)
I've seen talks by archaeobiologists who assert that the dinosaurs were simply broiled by the heat coming from the atmosphere. That theory nicely explains why small, burrowing creatures suddenly took off and why the seas weren't as strongly affected by the land: anything small enough to hide in a burrow, or agile enough to swim deep underwater for a few days survived (at least in numbers large enough to propagate); everything else was cooked. It is also consistent with the fossil record, which shows huge amounts of charcoal cinders near the K-T boundary wherever you look, and a drastic change in the types of pollen present.
Disclaimer: I am not a paleontologist, I'm only an astrophysicist.
The article says "global cooling" (Score:5, Interesting)
Not the first to suggest this.... (Score:3, Interesting)
Iridium layer (Score:4, Interesting)
Re:Volcanos and warming (Score:3, Interesting)
Balderdash. For starters, I don't "want" anything. This goes a long way toward freeing me from whatever the current fashionable hysteria happens to be. For seconds, things happen because of causes. Nothing happens "just because."
That's magic. There is no magic. If there is something to the "paranormal" it isn't paranormal. If it happens, it happens for reason. Reasons are normal.
This is, I think, what you mean by instability
Balderdash. If I stand my bicycle up, it falls over, because it is unstable. This hardly implies that it fell over for no reason.
false equating of weather behavior and climate behavior has been a major part of a well funded attempt to decieve the public
Bingo!
Skeptical about global warming?
I explicitly stated that I was not.
you can still save money by switching to solar
And in other threads I have explicitly stated that it's all about the Sun, all the time. My transportation needs are already 90% covered by solar energy (some non solar energy is used to create my solar energy). Are yours? I have no particular love for the smoke and soot belching monsters I have to share the road with. I'm not even all that fond of roads, per se. I have been an enviromentalist since a small child, before Silent Spring was published.
But I try not to let it make me stupid. My politics do not drive my science.
KFG
Re:What I have always wondered about... (Score:2, Interesting)
I went hunting the web to back up my armchair theory - that the Yucatan impact CAUSED the India lava flows directly (think bullet thru a ripe tomato)..
India is currently about opposite the Yucatan, but I'm not sure where the two sites were located 65 million years ago (How much continental drift?). BUT on the way to try to track down some semblance of support for my pet theory I found this article about a very large potential impact crater right beside India that hasn't yet made the impact database (it's not been decided either way):
But Chatterjee believes the geologic activity in India is best explained by a massive meteorite impact. For further proof, he points to alkaline igneous rock spires that are encased in the Deccan Traps. These spires are rich in iridium, but the Deccan lava did not contain iridium. How else, he asks, could the spires have formed if not by a nearby meteorite impact?
In addition, Chatterjee says there is an underwater mountain as high as Mount Everest within the Shiva crater. He says this structure has been dated to be 65 million years old, and he thinks it could be the central peak that is often seen within large impact craters.
Finally, Chatterjee says the crater contains shocked quartz, a key sign of impact. And because the K-T clay boundary layer in India is one meter thick - the thickest in the world - Chatterjee thinks a meteorite impact must have been close by.
Astrobiology Magazine - http://www.astrobio.net/news/print.php?sid=1281 [astrobio.net]
There is also mention of another impact crater in the Ukraine that is also 65 million years old.
So it sounds like we had more than 1 big meteor event, potentially cooking the atmosphere instantly, the shock waves might have instantly caused massive cracks in the earth's crust, and/or the kinetic energy absorbed from these could possibly warm up the earth's core enough to cause massive lava flows, the resulting gasses and or dust released in all these events would have yanked the temperature up and down, in short, the Dinosaurs had it from many interrelated sources effectively at the "same time" give or take a half a million years.
When you look at a cross section of the planet and see how thin the crust is, (http://www.seismo.unr.edu/ftp/pub/louie/class/10
My question is, say the crust is 50 kilometers (30 miles) thick (on average?) http://pubs.usgs.gov/gip/interior/ [usgs.gov]
How much thinner will it get if we raise the temperature of the atmosphere by 1 degree C?
Good thing rock is a decent insulator!
The other baffling thing is why we need to use greenhouse gasses to heat our homes when we are living on a ball of molten rock with a wafer thin coating on it? Is geothermal heat really too expensive to compete?
There, feeling safer now?
about those Indian volcanoes... (Score:4, Interesting)
On a global scale, a massive meteor impact would actually cause massive and very sudden volcanic eruptions on the opposite side of the Earth as it causes a wave of magma to concentrate on one very small spot.
Re:Volcanos and warming (Score:3, Interesting)
If you have Fear that the climate isn't warming you just might have a political bias. Uncertainy and Doubt are called "science." If you lack them, you aren't doing any. All you can legitimately do is define their limits . .
It is difficult to predict if your bicycle will fall to the left or to the right,. .
No. It's pretty simple really. In fact it was my field of research back in the 70s. Really. I can even determine which way it falls without fail. Just place the center of gravity to one side or the other of the axis. Boom. It goes down on that side.
Things get a bit more complicated if you're riding the bike, but as a general rule if you steer left it falls right and vice versa.
Now here's the part that's really relevant: the tricky bit is how you stop it from falling. That's why it took you so long to learn how to ride a bike.
And part of the answer is: You don't. It's unstable. It's always falling.
How long do you think it will take you to learn to "ride" the climate?
. .
That's what I said. Climate change happens. Predicting that is just as certain as predicting that the weather will change. Predicting how it will change is just as hard as predicting the weather. What allows the illusion of predicting climate change is that it happens slowly, whereas your weather prediction is going to be testable within a matter of hours, so when you fail it's pretty damned obvious. You're also reasonably safe at predicting the climate will continue to do whatever it's doing now. If it's been getting warmer for a couple of centuries, predict it will get warmer and Shazaam! You're a climate wizard.
Both phenomena are unstable, just over different periods.
Get back to me on your climate predictions in a couple hundred years and we can see how you did.
Just where is the axis and center of gravity of the climate anyway? And exactly how good are you at predicting volcanoes?
On the other hand, the factors that go into climate are many.
Exactly. Some of those things are rather hard to predict. In the agregate it gets even harder.
Insisting that it is the Sun alone is incorrect.
However insisting that it is driven by anything but the Sun is equally incorrect. You have noticed that it gets colder at night, haven't you?
How much slower does the Earth cool at night than it did 200 years ago?
"Daisyworld arguably demonstrates . .
A simple computer model. With feedback.
Put the Sun out and see what it does. You have noticed that it gets colder at night, and much colder in the winter, haven't you? All of your daisies, black and white, are dead. Tommorow. Throw in some foxes and fuzzy wuzzy bunny rabbits and they're still dead. The foxes and bunny rabbits are dead day after tomorrow. The fish will last a bit longer, but they won't be happy about it.
The Sun is the only source of heat. The Earth is embedded in what amounts to a heat sink of infinite capacity. In the absence of solar radiation it starts getting cold, really, really fast. Even with a bit of extra CO2. Daisies don't change that either. Even if they're plaid.
It's 7F and snowing outside my house right now, instead of 70 and raining; and all because my portion of the Earth is tipped just an itsy bit away from the Sun instead an itsy bit toward it. I'm inclined to believe that small variations in solar radiation can have a profound effect. Outside of simple computer models that is.
Inside a complex computer model with feedback any damned thing having no relationship to the real world can happen. You'd have to be a kook to beli