### gas:

Greenhouse gas
* Many greenhouse gases stay in the atmosphere for long periods of time.
* Most greenhouse gases can have effects
  - negative effects
* Most greenhouse gases come from natural sources
  - enter atmospheres
  - increase effects
* Most greenhouse gases occur in atmospheres
  - environments
  - naturally in the atmosphere
  - play roles
* Most greenhouse gases result from activities
  - human activities
* Some greenhouse gases absorb energy
  - radiation
* Some greenhouse gases affect climates
  - energy output
* Some greenhouse gases alter patterns
  - weather patterns
* Some greenhouse gases are carbon dioxide, water vapor, methane, and nitrous oxide
  - more potent at affecting climate change than are others
* Some greenhouse gases are produced by animals
  - facilities
  - humans
  - come from activities
* Some greenhouse gases have greater impacts on climate than others
  - help heat
  - occur naturally in the atmosphere, while others result from human activities
* Some greenhouse gases threaten health
  - public health
* absorb and re-radiate infrared radiation efficiently
  - retain heat from the sun
* act as the glass in a greenhouse
  - radiatively to warm the atmosphere
* affect climate by absorbing and emitting infrared radiation
  - energy output from the Earth, since they trap energy in the atmosphere
* are a natural part of the atmosphere
  - primary contributor to global warming
  - another source of air pollution
  - any gases that absorb infrared radiation in the atmosphere
  - both natural and manmade
  - gases which absorb visible light
  - global in their effect upon the atmosphere
  - in the earth's atmosphere
  - largely transparent to solar radiation
  - naturally present in the planet's atmosphere
  - ones that tend to trap solar energy or heat, causing the atmosphere to warm up
  - responsible for the greenhouse effect
* are the driving force behind global warming
  - steroids of the climate system
* block both incoming and outgoing radiation.
* can build up in the air and damage the ozone layer that surrounds the Earth
  - cause increased atmospheric temperatures
* cause global warming.
* change the climate and weather on our planet , Earth.
* come from natural sources too
  - sources, and also from human activities
* differ in their contributions to global warming
  - impacts on global temperatures
* emitted by human activity increase the amount of heat trapped by the atmosphere.
* es absorb energy that is radiated up from the Earth
  - are more opaque planetary radiation than for solar radiation
  - exist naturally in the atmosphere
  - hold in heat
  - raise the temperature of a planet by absorbing c
* have a warming effect on surface temperatures.
* include methane.
* make the polar winds blow stronger over the oceans, where they pick up warmer air.
* migrate so where they originate is irrelevant.
* pose a very real and significant threat to the world ecosystems
  - threat of global warming
* prevent heat energy from the sun escaping into space
  - from escaping from the atmosphere into space - just like a greenhouse
  - that energy from escaping into space
* provide insulation that traps some of the sun's heat energy.
* remain in the atmosphere for a long time after they have been released
  - many years and are globally distributed
* spur warm, wet winters.
* trap the heat of the sun, impacting the temperature on Earth.
* vary in their capacity to induce global warming.
* warm the atmosphere, no matter where they are produced on the globe
  - while aerosols tend to cool the atmosphere
  - planet by trapping heat from the sun in the atmosphere
+ Carbon dioxide: Organic compounds :: Biochemistry :: Greenhouse gases :: Oxides
  * Carbon dioxide is a greenhouse gas. Greenhouse gases trap heat energy. Greenhouse gases change the climate and weather on our planet, Earth. This is called climate change. Most scientists think that greenhouse gases are causing global warming, the rise of Earth's surface temperature.