Secular Café: Are We Driving Earth to an Irreversible Tipping Point?

Secular Café Serious discussion of science, skepticism, evolution, pseudoscience, and the paranormal

Are We Driving Earth to an Irreversible Tipping Point? Jun 18th 2012, 00:43 Scary stuff! Quote: Are We Driving Earth to an Irreversible Tipping Point? Nature changes gradually—until it doesn't. As the changes in an ecosystem pile up, they can push the system past a "critical threshold," and then the change can become extremely fast (in relation to geological timescales) and unstoppable. And in a review in the journal Nature, researchers suggest that the same thing is happening to the whole world: Humans could be driving Earth's biosphere towards a tipping point beyond which the planet's ecosystems will collapse abruptly and irreversibly. This global ecosystem collapse has occurred before, most recently about 12,000 years ago with the last transition from a glacial period to the current interglacial (i.e., warm) period, say the review authors. Over the relatively short period of 1,000 years, fluctuations in the Earth's climate largely killed off about half the large mammal species, along with birds, reptiles, and a few smaller mammal species. The millennium-long shift was triggered by rapid global warming, and once this warming pushed the planet past its tipping point, the end of the 100,000-year-old ice age became inevitable, giving way to the current 11,000-year-old interglacial era. Even as many Americans insist that we aren't affecting the environment, the paper's authors warn that man-made changes, such as loss of biodiversity, pollution, agriculture, climate change, and overuse of natural resources, are driving the planet toward another global tipping point. A few of these transformations, such as climate fluctuations and species extinction, also preceded earlier global critical transitions. And when scientists plug these transformations into ecosystem models, they quickly nudge systems past their tipping points. ... http://blogs.discovermagazine.com/80...tipping-point/

You are receiving this email because you subscribed to this feed at blogtrottr.com. If you no longer wish to receive these emails, you can unsubscribe from this feed, or manage all your subscriptions