Illustraion of how much sea level would fall if every ship were removed all at once from the Earth's waters The level falls about six microns — slightly more than the diameter of a strand of spider silk. Graphic: XKCD

How much would the sea level fall if every ship were removed all at once from the Earth’s waters? – Michael Toje
About six microns—slightly more than the diameter of a strand of spider silk. […] Sea levels will likely rise a few feet by the year 2100. Current fish wet biomass is about 2 billion tons, so removing them won’t make a dent either. (Marine fish biomass dropped by 80% over the last century, which—taking into consideration the growth rate of the world’s shipping fleet—leads to an odd conclusion: Sometime in the last few years, we reached a point where there are, by weight, more ships in the ocean than fish.) [more]

Ships via Ketsugami