Re: @ Matt
".....the ice sheet being thin enough to provide enough light to drive the occurence....." See, I warned you all it was a bit hard for the AGW crowd to follow. Triggerfish, you lot keep insisting that global warming will keep melting the ice, then that will make the ice even thinner. However, that means more light getting through the ice so more algae to absorb more man-made CO2, which you lot insist is the cause, meaning the warming could slow or stop and then the ice could thicken back again. Essentially, a feedback process. Do you need a diagram? In crayon, maybe?