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Dinosaurs Died Within Hours of Asteroid Impact, says New Study
colonist writes "SPACE.com reports that most dinosaurs were incinerated within hours by the 'heat pulse' of an asteroid impact 65 million years ago. The study 'Survival in the first hours of the Cenozoic' presents a scenario where the only survivors were underground or were underwater in swamps or oceans. All unprotected creatures were 'baked by the equivalent of a global oven set on broil.'"
the consensus is: The asteroid that killed off the dinosaurs is the one that hit in the Yucatan Penninsula The asteroid that killed off 99.9% of life before the dinosaurs existed was the one that hit near austrailia
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"Alvarez Hypothesis" is the term used to describe the idea that dinosaurs died as a result of a catastrophic asteroid impact. I do not believe that the hypothesis has attained the status of theory, however. The main evidence for such a hypothesis seems to come from the observation of geologist Walter Alvarez of a significant layer of Iridium on the Cretaceous-Tertiary boundary (KT boundary), due to the fact that Iridium is a very rare element on Earth but found in abundance in asteroids and meteorites. This link has some more information along with Wikipedia.
I think you're talking about two different mass die-offs. The Yucatan crater theoretically caused the Late Cretaceous die-off (approx. 65 million years ago) that made the dinosaurs go extincet. The Australian crater has been linked to the Late Permian die-off, which happened about 250 million years ago.
So, Racer X, the scientific community would appear to have two consensuses (consenses? WTF?), one on each of the two issues.
Mass extinctions are a fairly regular event in the Earth's geologic history. There are at least two more, besides the Permian and Cretaceous catastrophes, with which I'm familiar. Most people only get taught about the Cretaceous one in high school, though, so they never hear about the others.
Kind of like the Ice Age. Up until I was 16, I only thought there was one. Turns out there were a shitload of them.
To be more exact for your "a lot of energy" required to raise water over the air - it is about 4 times as much energy for water than air. That is because the specific head of fresh water is 1 (Ocean water is .93) while the specific heat of air is only .25. Thus it takes 4 times as much energy to raise 1g of water 1 degree Celcius as compared to a gram of air.
This doesn't at all take into the account the fact that the starting temperature of the air is higher than that of the water. The average temperature of water in the oceans is just a bit above freezing in the pole areas and is about 17C(62F) on average (max 36C). The average temperature of air is much higher due to being over landmasses. Thus heating all of the air is MUCH easier than water.
Also the density of air is much lower, so heating the same *volume* of water takes even more energy compared to air.