How do Green House Gases contribute to Global Warming?

Question

hmmm. can you help me.

Answer 1

Some gases ("greenhouse gases") let sunlight in, which warms the Earth, and then block that heat from leaving. That's the "greenhouse effect", and it's a natural thing, mostly caused by water vapor.  It's like putting a blanket on the Earth.

Man is making excessive amounts of greenhouse gases, mostly by burning fossil fuels. That causes the delicate natural balance to go out of whack and the Earth warms. That's global warming.

It won't be a Hollywood movie style disaster. Gradually coastal areas will flood and agriculture will be damaged. But it will be very bad. Rich countries will cope, but it will take huge amounts of money. In poor countries many people will die of starvation, but not all of them.

Most scientists say, in 20-50 years. But we need to start right now to fix it, fixing it will take even longer than that.

Really good website for more information here:

http://www.nrdc.org/globalWarming/f101.a...

Answer 2

Basically,  the gases trap more of the sun's rays in the Earth's atmosphere, creating heat.

Answer 3

Water vapour, the most important "greenhouse" gas, keeps the earth about 30 C warmer than it would ordinarily be, so they are crucial to keeping earth warm.

Water vapour, along with some others like CO2 and methane, prevent re-radiation of heat into space, so the earth has to warm up a bit to stay in an energy balance.

By the way, a greenhouse with plants, does not stay warm because of the "greenhouse effect".  It stays warm because hot air is prevented from escaping by the glass (or plastic).

Answer 4

Green house gas actually damages the ozone layer which as a result causes global warming.

Answer 5

http://dels.nas.edu/dels/rpt_briefs/clim...  <== here's a good description.

in simple terms, they trap heat, much like an extra blanket you put on your bed in the winter.

more specifically, CO2 reacts with specific radiation frequencies.

CO2 generally does not react with the frequencies found in light.

CO2 does react with the frequency (energy level) found in infrared radiation.

so, CO2 ignores light coming from the sun during the day.

however, CO2 absorbs infrared radiation, often found at night when the earth is cooling, and then re-radiates the energy.  some of that energy is still lost to space.  however, some is radiated toward the earth, keeping the earth warmer.

methane,  CH4,  does the same, as does clouds.  i assume that you've noticed that on cloudy nights, it does not get as cold as it does on clear nights.

in total, water vapor is the strongest greenhouse gas.  w/o it, the earth would be well below freezing.  however, our society is intimately related to the current temperature, and any change at all, in either direction, would likely diminish food production.

have a nice day.

Answer 6

Greenhouse effect is very analogous to the  way a greenhouse works. Greenhouse does of course contain some air that gets warmer, but the most significant way the  glass of the greenhouse works to accomplish this is to reflect long wave radiation, or heat.

Well, greenhouse gases do most of their work in the daylight just as does a greenhouse. Most heat is reemitted from solids and liquids within a couple hours of being originally absorbed.

When you notice that clouds hold in more heat than a clear sky, at night, that is not, repeat not the greenhouse effect, any more than the reflection of the sun from the top of the clouds in daylight is grenhouse effect.

Reflection of light and heat by clouds is a distinct process. When we discuss water vapor in the greenhouse effect, we are clearly not referring to clouds. Clouds are a major cause of reflectivity which in general cools the earth.

But water vapor, humidity that does not condense into droplets of cloud, is very different. Humidity does not reflect sunlight as a whole, but it does selectively block long wavelength radiation, heat.

When you go out in the sunlight you are feeling 3 main kinds of radiation: Ultraviolet, very short wavelengths  that will either bounce off  earth and go away, or be absorbed. Visible light, which is intermediate in wavelength, and heat.

Now the part that is heat is not coming from the sun. It is being reflected by greenhouse gases.

That heat comes to us from all directions, not particularly the sun's  direction.

When our skin absorbs light or ultraviolet, our skin does warm up. That comes from the sun, and is mostly coming to us directly from the sun. On a cloudy day, the cloud will reflect some of the sunlight, and will scatter some of it before it gets to us. The cloud will also reflect some light and heat back to us after it bounces off the earth.

Global warming causes us to have less cloud cover even though we get more humidity, more water vapor. So it is accurate to  say that global warming causes an increase in greenhouse gas, specifically water vapor.

But, because of reduced cloud cover, we will also see drought, and with that we will see plants absorb far less CO2, another GHG. So global warming causes another increase in GHG.

Global warming can cause oceans to begin releasing CO2 if the ocean surfaces themselves warm up. Warmer soils cause more rapid decomposition of plant material, again releasing CO2. Global warming can result in release of methane stored in the arctic ice.

All of this is significant because increase of those gases as a result of global warming is an important part of the explanation of how global warming took place without the assistance of human activity, hte burning of fossil fuels.

Now whether global warming causes greenhouse gases, or greenhouse gases cause globlal warming, and it works both ways, we get increasing temperatures and increasing GHGs each of which causes the other. We get clear skies leading to warming of the oceans. Then, when the oceans are sufficiently warmed, they can sustain evaporation that provides global precipitation, including snow toward the poles, and so a major ice age.

It takes a lot of stored energy to evaporate many metres of water from the oceans and deposit it as snow on the northern regions, and it all starts with a bit of global warming.

Can we stop it?  Probably not possible with just reduced emissions, important as that is.

Answer 7

To put it simply, the gases trap in the heat that the sun puts out in our ozone layer. This causes the earth to warm. I.E. Global warming.

Answer 8

Green house gases form a layer that keeps the heat in at night when the sun sets.  Without it we would freeze every night.

CO2 is a very minute part and human activity contributes maybe 0.03% towards the green house layer, so it's not possible to say we have any effect on it.

Nevertheless, it's a good thing and so is CO2.

Most scientist now agree that the warming and cooling cycles are completely normal and humans have no affect on the climate.  We don't cause these cycles and we can't do anything about them.  

There are some who would have you believe otherwise, but they have an agenda that's not good for our economy and they hope that they can use guilt to make people accept the man-made global warming hoax.

History shows that CO2 levels have been much higher in our history and the ice core samples prove that CO2 increases about 800 years after each warming cycle.

So conclusively CO2 does not cause warming, it's the other way around.

With so much disinformation, I hope the truth gets through.

Answer 9

Greenhouses gases are gases that cause the greenhouse effect. They form a layer around the Earth. Here's what happens:

Light from the Sun passes through the gases, hits the ground, becomes heat and floats back upward (heat rises).

The heat gets trapped by these gases like a blanket, heating up the Earth.

These gases include:

carbon dioxide (CO2)

water vapor

methane