— Do they consider the effect of evaporation? Earth loses some of its atmosphere to space constantly and it's not too improbable that some water vapor is also lost in this way...
— What? what water bleeds into space?
— Better believe it - what with anthropogenic global warming and all...the water will all just boil away and earth will become one giant desert . Just give it enough time, that's all.
— Raise worms. Produce spice. Profit!
— somewhere in slashdot.org