The 11th Hour (16 of 49)

The 11th Hour

we hear about people who "l believe in" or "l don't believe in" global warming...
as if this were somehow some object of religion, as opposed to based in evidence.
And scientists look at evidence.
The scientists have a tremendous amount of agreement...
over some of the basic principals of global warming.
Is the Earth warming? Absolutely.
Is some portion of the warming due to human activity? Absolutely.
These are things that, there's a consensus in the international scientific community.
There's no doubt about that.

The natural changes-- The speed of the natural changes is now dwarfed by human changes...
to the atmosphere and surface.
Jim Hansen, who is the director of the NASA lnstitute for Space Studies...
recently gave a best estimate that was based on research done last year.
And the current estimate is that the Earth has warmed up...
by about seven-tenths of a degree centigrade.
And even if we were to cap CO2...
carbon dioxide emissions to the level they are now...
the Earth should still warm by an additional half a degree centigrade.
That's been enough to melt 20 percent of the sea ice in the Arctic.
It 's been enough to speed up the spin and duration of hurricanes about 50 percent.
It 's been enough to start the permafrost...
beneath the tundra across the north melting.
Even at the low range, a couple of degrees in the average...
really changes things in places.