Study: Climate Change At Its Fastest Since Extinction Of Dinosaurs

[damnedifIknow]

AMARILLO, Texas (CBS Houston/AP) – A report issued out of Stanford University is claiming that the Earth’s climate is changing at its fastest rates since the time of the dinosaurs’ extinction approximately 65 million years ago.

“Humans have never seen anything like this,” study co-author Christopher Field observed to Scientific American.

According to their study, which was published in the journal Science, the rate could even increase moreso from where it is presently."

n order to reach their conclusion, the pair reportedly examined every major weather event or climate transition since the dinosaurs were rendered extinct, including the time during which the planet emerged from the ice age."

At that time, temperatures were said to have increased at a rage of 3-5 degrees Celsius – on par with today’s climate shifts. However, those earlier changes occurred over a period of about 20,000 years, while today, they are happening within the span of decades, the researchers told Scientific American."

http://houston.cbslocal.com/2013/08/06/study-climate-change-at-its-fastest-since-extinction-of-dinosaurs/

[Igel]

1. Damned if I know.

There's the little problem of granularity in the data. We have data that's good for each year for the last century or so. We have proxy data going back year by year for a while longer--depends how fine grained you want your proxy data.

Past that you start having ice core samples and marine sediment layers, and those aren't fine grained. A decade or, after a few thousand years BCE a century, won't show up except to skew the average slightly. That 20k-long increase may not have taken that long if it occured 40 million years ago, but we can't tell. We get averages and trends.

The core assumption is that nothing will cause the T range to shift back down by a degree celsius or so. I doubt something will do that, but the models have been wrong in the past so there's no real reason to expect that they're necessarily accurate now. "We didn't account for X and now we've fixed the problem" only works the first dozen times or so, then you can pretty much rule out infallibility and omniscience. But if this happened, there'd be scant trace of the decades-long increase.

The other core assumption is that the trend will continue. We're maybe 1 degree above the average for the period we usually like to consider as baseline, not 3-5.

[marions ghost]

2. From the Scientific American article:

Mitigation, adaptation needed

The rapid pace of climate change, Field said, "really sets a schedule by which adaptation changes need to be made." That includes such moves as flood protection and building different kinds of structures.

Some of the changes to the planet cannot be stopped because the temperature increase is unavoidable. But the scientists emphasized that people do have the ability to affect the severity of the shifts.

To hold the temperature increase to about 1.5 degrees, the globe would need to cut its greenhouse gas emissions to zero by 2050, and then have negative emissions, meaning "the sum of all human activities is a net removal of CO2 from the atmosphere," the study says. If that happens, changes by the end of the century will be less severe, Field said.

But it will require transitioning away from fossil-fuel-based infrastructure over the next few decades, he said. If fossil fuels are burned after that, he said, it will have to be with the capture of carbon pollution.

There are many obstacles to this outcome, the Stanford paper says.