On Mon, 21 Mar 2005 10:43:53 +1000, you wrote: > At 09:17 AM 21/03/05 +1030, you wrote: > >> >>Last week I heard the most hilarious bit of environmental news I've >>ever encountered. It seems there's a report that points out that >>"heavy water" (water where at least one of the hydrogen atoms is a >>heavier isotope such as H3 Tritium) evaporates less readily than >>normal water. So as the world warms and evaporation increases, the >>percentage of heavy water in our waterways will increase, leading >>to our drinking water becoming radioactive as global warming >>intensifies. Sorry I can't provide a reference, it was an article >>on the news on the radio. >> >>Needless to say, that's one of the most farcically innane bits of >>hyperbolic scaremongering bullshit I've ever heard: it's playing to >>the fears of people who buy-in to greenhouse, and who understand so >>little about radioactivity that they think any conceivable increase >>in heavy water resulting from evaporation could be significant. But >>this is the kind of stuff the environmental movement pumps out onto >>our airwaves all the time... > > I'm sorry I missed it! > > Even more farcical when you realise that "heavy water" is water where the > hydrogen atoms each have an extra neutron in the nucleus. These hydrogen > atoms are called deuterium and are non radioactive. Tritium has two extra > neutrons and is radioactive and has a half life of 12 years or so IIRC. > Hence there isn't any left over from the formation of the universe. There > probably is a *very* small equilibrium concentration of tritium on Earth > from production by cosmic ray collisions followed by radioactive decay. > The rest of the tritium is man made in nuclear reactors and last I heard > was still in production and is used in the core of fission weapons to boost > the output and in some types of optical equipment. > > By the way don't go drinking heavy water even though it is not radioactive. > I did see where the heavy water substituted for normal water chnages > osmotic pressure in your cells. Don't hold me to that. > > > The sad thing about all this is that our lives will be governed by and > options constrained by, decisions made on completely spurious grounds by > people who haven't the faintest idea or understanding. > > Mike
Aside from considerations of the lack of danger from such isotopes, the water regime on planet earth is a closed one, so if the overall evaporation increases, so does the rainfall, so the average dilution of the isotopes in the reservoirs won't change much at all, and any change will only be a redistribution of dilutions. i.e.some reservoirs may have a slightly increased concentration but others will have reduced concentration. Cheers, John G. _______________________________________________ Aus-soaring mailing list [email protected] To check or change subscription details, visit: http://lists.internode.on.net/mailman/listinfo/aus-soaring
