I’ve always read about global warming, and the greenhouse effect, and such. It seems logical and makes sense to me. However, after thinking about it further, I’ve come up with a question. We’re releasing a whole bunch of bad chemicals into the air that are making “holes” in the atmosphere, right? So that makes it so that more of the sun’s rays can get in. But I’ve also heard that the chemicals we’re releasing are increasing our atmosphere which would make it more difficult for the sun’s rays to get in, or out? or both? If they can get in, but not out, why? that doesn’t make any sense. If a chemical is destroying the atmosphere, making it thinner, the heat will go straight to us on the planet, therebye making it warmer, but would it also make it colder, such as mars, depending on which way the planet it facing in relation to the sun?
The way the Greenhouse Effect works is such that chemicals alter the athmospheric structure so that it traps heat in.
You see heat is a form of radiation. What happens is various forms of radiation such as visible light and a few others having been emitted by stars, almost totally our own sun, are able to pass through such athmospheres to the surface where they are absorbed and then some of it is re-emitted as heat. And it is this re-emitted heat which gets trapped and causes the Greenhouse Effect.
Oh, so that chemicals only trap the heat in the form it is after it bounces off the earth? Now it makes sense. Thank you, I can now sleep at night.
If you do a google image search for “Greenhouse Effect” you’ll get a lot of diagram that might be interesting to see. Look for those at .edu sites, NASA and NOAA sites.
Sleep well!
And welcome to the SDMB.
You’re confusing the greenhouse effect with the ozone hole. This is quite common (most people don’t know their their global warming from their ozone hole).
Global warming is the idea that (mainly) carbon dioxide traps heat just like a greenhouse. We keep pumping more CO2 into the atmosphere, so this problem is just getting worse, although there is considerable difference of opinion in how bad it is/will be.
The ozone hole is thought to be caused by fluorocarbons (like freon) which destroy ozone high in the atmosphere. For some reason, the area over Antarctica gets an annual hole where the ozone is especially thin. This year the hole isn’t as bad, leading many to the conclusion that efforts to reduce ozone-destroying chemicals are working. Ozone, by the way, is the chief filter of ultraviolet rays, which cause skin damage, not global warming.
[minor nitpick]
IIRC, the radiation doesn’t quite bounce off the earth and get trapped. It comes down as high-energy short-wave radiation, which passes through the Greenhouse Gasses (GHGs). It hits the planet, and warms it up. This warmth is then re-radiated (not ‘bounced’) into the atmosphere. Think of a blacktop – you don’t necessarily feel all of the heat coming down on a summer day, but you can feel it coming off of the tar. This re-radiated heat has less energy (is that the right term?) and is emitted as longer-waved infrared radiation. This type of radiation can’t pass right through the GHGs, rather it is absorbed by them. They now have the energy, and will eventually re-radiate it again. This trapping, blanketing effect is what gives rise to the much needed Greenhouse Effect in the first place. What anthropogenic sources of GHGs are doing is putting more heat-trapping molecules into the atmosphere, so that there is more energy being kept in the system.
Of course, people are welcome to correct me.
Another confusing thing is that ozone is also a greenhouse gas. Ozone in the ozone layer is good, but ozone in the lower layer of the atmosphere (what’s it called again?) is bad.
So did banning all those spray cans really help with the ozone or was it too little too late?