0:00the assumption some like this the earth is so big
0:03we can't possibly have any lasting harmful
0:06impact on the earth's environment and maybe that was true at one time but it's
0:11not anymore
0:12and one of the reasons it's not true anymore is that the most vulnerable part
0:17of the earth ecological system is the atmosphere
0:21voluble because is sold them
0:25my friend the late Carl Sagan used to say if you had a big globe with a coat
0:30of varnish on it the thing is though that varnish relative to that global
0:35it's pretty much the same as the thickness of the Earth's atmosphere
0:39compared to the earth itself and its thin
0:43another of that we r cable love changing
0:46its composition that brings up the basic science of global warming and I'm not
0:51going to spend a lot of time on this because
0:53you know it well but sun's radiation comes in
0:57in the form of light waves and that heats up the earth and then
1:00some of the radiation that is absorbed in warms the earth is really radiated
1:06back into space
1:07in the form of infrared radiation and summer the outgoing infrared
1:12radiation is trapped by this layer
1:15%uh atmosphere and held inside the atmosphere and that's a good thing
1:20because it keeps the temperature uva earth with them
1:23certain boundaries keeps it relatively constant
1:26and livable but the problem is this thin layer about miss fear
1:30is being ficken by all of the global warming pollution that's being put up
1:36there
1:36and what that does is it thickens this
1:40layer that must fear more of the outgoing infrared
1:44is strapped and so the atmosphere heats up worldwide that