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'Great Dying': Rapid Warming Caused Largest Extinction Event Ever, Report Says (theguardian.com)
An anonymous reader quotes a report from The Guardian: Rapid global warming caused the largest extinction event in the Earth's history, which wiped out the vast majority of marine and terrestrial animals on the planet, scientists have found. The mass extinction, known as the "great dying," occurred around 252m years ago and marked the end of the Permian geologic period. The study of sediments and fossilized creatures show the event was the single greatest calamity ever to befall life on Earth, eclipsing even the extinction of the dinosaurs 65m years ago. Up to 96% of all marine species perished while more than two-thirds of terrestrial species disappeared. The cataclysm was so severe it wiped out most of the planet's trees, insects, plants, lizards and even microbes.
The researchers used paleoceanographic records and built a model to analyze changes in animal metabolism, ocean and climate conditions. When they used the model to mimic conditions at the end of the Permian period, they found it matched the extinction records. According to the study, this suggests that marine animals essentially suffocated as warming waters lacked the oxygen required for survival. The great dying event, which occurred over an uncertain timeframe of possibly hundreds of years, saw Earth's temperatures increase by around 10C (18F). Oceans lost around 80% of their oxygen, with parts of the seafloor becoming completely oxygen-free. Scientists believe this warming was caused by a huge spike in greenhouse gas emissions, potentially caused by volcanic activity.
The researchers used paleoceanographic records and built a model to analyze changes in animal metabolism, ocean and climate conditions. When they used the model to mimic conditions at the end of the Permian period, they found it matched the extinction records. According to the study, this suggests that marine animals essentially suffocated as warming waters lacked the oxygen required for survival. The great dying event, which occurred over an uncertain timeframe of possibly hundreds of years, saw Earth's temperatures increase by around 10C (18F). Oceans lost around 80% of their oxygen, with parts of the seafloor becoming completely oxygen-free. Scientists believe this warming was caused by a huge spike in greenhouse gas emissions, potentially caused by volcanic activity.
Ironically, the Green House effect is a purely quantum mechanical one. We can calculate the absorption spectrum of small molecules down to 10 digits, including those of carbon dioxide, water and methane.
Consider that we find dinosaur fossils. If there was a civilization that created ever somewhat durable artifacts, we would know.
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In the 1970s, greenhouse effect models correctly predicted that the aerosol cooling trend that dominated global climate between 1940 and 1980 would be reversed in the coming decades. And if you apply an impulse response filter (like moving average) to smooth out year-to-year weather effects, the predictions of those models as to global temperature anomalies hold up extremely well.
This is the strongest possible confirmation you can have for a scientific hypothesis, which is why the burden of proof is on people who make claims like the earth is not warming, or that anthropogenic CO2 emissions can't drive climate change. You can call the people who support AGW "chicken littles", but here's the thing: even if that were true, it wouldn't matter. The emotional basis of your beliefs has no relevance at all. It's what you claim and how you support it.
You can be a Young Earth creationist and a good scientist, as long as you don't make any unsupportable creationist claims in a scientific forum. In church you can say anything you damn well please.
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Again, it is just a bad example. I am a physicist, and the turbines on a car misconception is one of those exceptions that is actually viable for certain conditions, which may be why some people intuitively cling to it.
Consider a car at rest pointing into the wind. The fans generate power while no work is done by the wheels and nothing is lost to drag. Obviously some forward motion is possible before things come to equilibrium. Working it out, that equilibrium happens at a bit faster than the windspeed.
So it won't work on a highway commute (and would in fact be detrimental) but it isn't a totally wrong direction for casual intuition to take you. Sailboats sail into the wind, using the wind speed differential as power in an analogous way.