oceans
one of the predictions of global warming is rising sea levels. observations say they haven't budged. why not? heh. the first question is, should they? okay. here's a back of the envelope calculation. assume water expands by 0.03% per degree celsius. and assume we're going to raise the temperature of the water by 1C to a depth of 100 meters. let me do the math here... that's uh 3 cm. everybody panic. oh wait. maybe it's melting ice. hrm. if you melted all the ice on earth you'd have enough water to raise sea levels some 66 meters. that's some 200 feet for those of you still not hip to that newfangled metric system. everybody panic. oh wait. it takes energy to melt ice. that energy has to come from the sun. suppose we focused *all* of the energy from the sun that strikes the earth to melting ice... it'd take more than 600 years to melt it all. ergo we can conclude it's physically impossible for sea levels to rise faster than 11 meters per century. the sun is a big candle that burns remarkably steadily. it varies by some 0.1% during the sunspots cycle. if we assume all of that excess energy goes to melting ice, we predict a sea level rise of 10 cm per century. or 0.1 mm per year. everybody panic. yeah, right.