Wow. It's the thermohaline conveyor in action---or lack of it. And that mechanism what I'm personally watching with interest. A bobble in the Great Conveyor means a Little Ice Age: we migrated to America in the midst of one. A big bobble means a major reglaciation, read big Ice Age. It will be ironic if all the people who've decried the possibility of global warming [because they envision a global heat wave and desertification] end up shoveling lots and lots and lots of snow while the equator turns muggy and drowns in rain. The planet has corrective mechanisms, and much as some critics of global warming theory want to talk about self-correcting 'natural cycles', the upshot of it is that if a correction gets triggered, the correction is on a planetary scale---which is pretty big, in terms of our comfort zone. Even my love of ice and snow has some limits.