Corals

The way I look back in the past is by using the fossilized remains of deep-water corals. You can see an image of one of these corals behind me. It was collected from close to Antarctica , thousands of meters below the sea, so, very different than the kinds of corals you may have been lucky enough to see if you've had a tropical holiday. So I'm hoping that this talk will give you a four-dimensional view of the ocean. Two dimensions, such as this beautiful two-dimensional image of the sea surface temperature . This was taken using satellite, so it's got tremendous spatial resolution. The overall features are extremely easy to understand. The equatorial regions are warm because there's more sunlight. The polar regions are cold because there's less sunlight. And that allows big ice-caps to build up on Antarctica and up in the Northern Hemisphere.