-- takes it where exactly, is what I want to know -- deep into outer space, or to some other place where it is lost forever and ever, never available again for any human, bovine or plant to drink? Is that what they mean, exactly?
Do they know what they mean? Exactly?
I don't mean to minimize water shortage problems, or problems caused by livestock farming. But I do think it is senseless to try to to discuss problems if we don't know what we're talking about. Water is absorbed by plants and animals, and escapes from them again by evaporation and urination and other means, and vaporizes into clouds, and rains down from clouds and is gathered in lakes and streams, and a lot of it goes into the oceans, but some of the salt water in the oceans evaporates into freshwater clouds, and some of that ends up in the lakes and streams again, not to mention the canals and reservoirs -- and yes, some of it actually does escape the Earth's atmosphere and go into outer space -- and my points are 1) that these processes are complicated, and 2) that the problem currently is not so much a lack of water, as a lack of clean, fresh water in certain areas. The problem has less to do with the overall quantity of water on Earth than with the quality of the water in specific areas.
And to make it more complicated, just one example: if we resort to large desalination of ocean water to meet the fresh-water requirements of humans and cows and grass and corn and so forth -- at some point we're going to think about all of that life back in the ocean that needs saltwater.
I'm not asking you to stop caring about such things. Vegans, I'm not asking you to stop raising Hell. I am asking you, however, to ask yourself whether a meme contains solid information before you post it on Facebook. All you can do, by being careful about such things, is make your case stronger.