We are the Asteroid - Scientists’ Heighten Concerns About Global Extinctions

This is a re-post from Yale Climate Connections

The global rate of extinctions, “already very large,” is “ramping up” . . . with climate change helping bring about that “acceleration,” scientist James White of the University of Colorado cautions in this month’s “This is not Cool” Yale Climate Connections video.

White’s concerns over extinctions are echoed by scientists James Hansen of Columbia University, Eric Rignot of the NASA Jet Propulsion Laboratory, Gerardo Ceballos of the National University of Mexico, Jonathan Payne of Stanford University, Lee Kump of Penn State University, and Stephanie Kitkiewicz of MIT.

Rignot, for instance, cautions that the loss of biodiversity resulting from extinctions is perhaps “even bigger” than sea-level rise. And Ceballos says an under-appreciated concern is that there are countless species of plants, animals, and microbes on Earth that humans do not even know about: so many species not having a scientific name that “we don’t even know” the extent of the losses.

To Payne of Stanford, a particular concern is that the rate of species loss the world is experiencing is “much much higher” than the rate at which species naturally originate, with the inevitable result that global diversity is being reduced. Kump of Penn State says the current rate of species extinction is 10 times that of massive extinction events that have occurred previously, and he points to climate change and the high incidence of volcanoes as a “common threat” in those extinctions. Ceballos notes that some 75 percent of medicines in use come from plants and animals in the wild.

Journalist and book author Elizabeth Kolbert, says the public is “sort of inured” to news of extinctions and therefore think they are natural. That’s not the case, she says.  She points to the scientific consensus that an earlier massive extinction of Earth’s species was caused by an asteroid impact; she says some scientists have spoken to her of their concern that “We are the asteroid.”

Posted by greenman3610 on Wednesday, 5 August, 2015


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