The end of the dinosaurs.
Cold water corals, meteorites, new greenhouse gases
22 May 2012
This week in the Planet Earth Podcast: scientists describe why the planet's least understood but most diverse species of coral is under threat. Also, what the meteorite strike that wiped the dinosaurs out would've been like; and why CO2 isn't the only greenhouse gas we should be worried about.
When you picture a coral reef, your first thought will probably be of a beautiful blue sea teaming with multi-coloured fish. But it turns out that that image is way too narrow, because this isn't the only type of coral.
Cold water corals - only discovered around 20 years ago - are widespread in the world's oceans. But they're much deeper that the reefs we're more familiar with. And despite their recent discovery, scientists have found that they already face a host of threats. Richard Hollingham speaks to Murray Roberts and Laura Wicks from Heriot Watt University to find out the scale of the problem.
Later on, Sue Nelson meets Penny Barton from the University of Cambridge to learn about the meteorite strike that wiped out the dinosaurs and created the gigantic Chicxulub crater in Mexico.
Click the play button above to listen now.
A full text transcript is available.
Finally, Johannes Laube introduces Richard to some scarily potent greenhouse gases, which he says can stay in the atmosphere for thousands of years. As if that's not bad enough, scientists are struggling to keep pace with the speed the chemical industry is coming up with new gases.
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