The Greenhouse Effect Lesson PDF

The Greenhouse Effect Earth’s Climate System Earth’s climate system moderates Earth’s temperature by trapping and storing energy from the Sun and distributing it As a result, around the air temperature the world. remains relatively constant across large regions of the Earth....

The Greenhouse Effect Earth’s Climate System Earth’s climate system moderates Earth’s temperature by trapping and storing energy from the Sun and distributing it As a result, around the air temperature the world. remains relatively constant across large regions of the Earth. Without a climate system, Earth would be much colder! The average global temperature would be about -18° C! The Greenhouse Effect The greenhouse effect is a process that occurs when gases in Earth's atmosphere trap the Sun's heat, keeping us warm! Natural vs Anthropogenic Natural Greenhouse Effect a natural process for millions of years thermal energy is absorbed by the atmosphere, keeping the temperature on the Earth that supports life. Anthropogenic Greenhouse Effect an unnatural process resulting from human activities thermal energy becomes trapped in the atmosphere, Earth’s Greenhouse Gases Solar energy absorbed at Earth's surface is radiated back into the atmosphere as heat (thermal energy). As the heat makes its way through the atmosphere and back out to space, greenhouse gases Earth’s Greenhouse absorb much of it. Gases: Carbon dioxide Water vapour Methane Ozone Nitrous oxide Carbon Dioxide Natural sources: volcanic eruptions, burning of organic matter (forest fires), and cellular respiration of plants and animals. Carbon Sinks: things that absorb CO₂ from the atmosphere and store the carbon in another form → important to keep CO₂ balanced in the atmosphere. Examples of Carbon Sinks: Forests → plants take up CO₂ to use for photosynthesis. Oceans → CO₂ readily dissolves in water, marine plants  Water Vapor accounts for 2/3 of Earth’s natural greenhouse effect the amount of vapor in the air depends on the temperature of the atmosphere warmer air holds more water vapor → traps energy the more vapor in the air, the warmer Earth becomes this type of relationship is called a feedback loop.  Methane Natural Sources: plant decomposition and animal digestion Methane absorbs more thermal energy than CO₂ making it a very powerful greenhouse gas! Example: Cows, sheep, and goats have bacteria in their stomachs to aid digestion. This bacteria also produces a whole lot of naturally smelly methane gas!  Ozone Ozone exists naturally in an upper layer of the atmosphere called the stratosphere → protects us from the sun’s UV rays. Nitrous oxide Natural Sources: by-product of bacterial reactions in soil and in the water, especially oceans. Example: animal waste gets decomposed by bacteria producing various compounds including nitrous oxide. Nitrous oxide absorbs 300 times more thermal energy than CO₂ making it a very powerful greenhouse gas!