Earth's Changing Atmosphere

Page 1

Chapter 1 – Earth’s Changing Atmosphere Section 1.3 – Gases in the atmosphere absorb radiation


Objectives • BEFORE, you learned • Solar radiation heats Earth’s surface and atmosphere • Earth’s surface and atmosphere give off radiation • The ozone layer is in the stratosphere

• NOW, you will learn • More about how radiation and gases affect each other • About the ozone layer and ultraviolet radiation • About the greenhouse effect


I. Gases can absorb and give off radiation • The atmosphere can affect light in four ways

– It can absorb light – It can reflect light – It can let light pass through – It can emit (give off) light


• There are forms of radiation humans cannot see

– Visible light – light that we are able to see with our naked eye, made up of the 7 colors ROY G BIV = white light – Ultraviolet radiation – waves that have more energy than visible light (higher frequency) – Ultraviolet radiation can cause sunburn, skin cancer, damage to your eyesight, paint, plastic, harm crops, etc – Infrared radiation – waves that have less energy than visible light (lower frequency) – Infrared radiation usually warms the materials that absorb it – Electromagnetic Spectrum – everything from what we can to what we cannot see. It includes UV rays, X-rays, Microwaves, Gamma rays, TV/radio waves and visible light


II. The ozone layer protects life from harmful radiation

• Ozone – is made up of 3 atoms of the oxygen element

• The ozone protects life by absorbing harmful UV rays from the sun • The ozone layer is located in the second layer (stratosphere)


III. The greenhouse effect keeps Earth warm. • The Greenhouse effect is gases that absorb and • • •

emit infrared radiation, which keeps energy in Earth’s system for a while Greenhouse gases give off infrared radiation Examples of greenhouse gases: carbon dioxide, methane, water vapor, nitrous oxide, and other gases that absorb and give off infrared radiation If the atmosphere had no greenhouse gases, Earth temperature would only be -18 degrees C/ 0 degrees F


• Atmosphere without

• Atmosphere with

Greenhouse Gases - infrared radiation would go straight through to outer space - water freezes and too cold for most forms of life on Earth to survive

Greenhouse Gases infrared radiation is kept within our atmosphere - water stays in liquid form


Turn static files into dynamic content formats.

Create a flipbook
Issuu converts static files into: digital portfolios, online yearbooks, online catalogs, digital photo albums and more. Sign up and create your flipbook.