Jack May wrote:
"Stephen Harding" wrote in message

Once H2 fueled vehicles come on line in perhaps 10-15 years,
their by-product of combustion will be water vapor.

Water vapor is much more effective "greenhouse gas" than
CO2.

But the atmosphere can only hold so much water vapor before it falls out of
the sky as potential fuel; rain. Water vapor will probably not effect
greenhouse problems very much.

I think I read that during the Carboniferous period that
the earth was as hot as it has ever been.

ISTR that one of the reasons was due to large amounts of
water vapor in the air (volcanoes? geothermal activity?).
Can't remember what the source of it was. Maybe just
evaporation from oceans.

At any rate, the air can be very heavily saturated with
water without it raining, or without rain clearing up
the humidity. Check out many of the tropical locations
of the world where heavy rains don't lessen humidity.

Perhaps H2 powered SUVs will bring on a glacial cooling
period when all that SUV derived water vapor freezes
into snow and ice in Minnesota and Canada, feeding
glaciers and burying our cities!!!

Wow, those SUVs are really something, huh?


SMH