effects+of+human+activities


 * //Effects of human activities// **


 * Videos**

About the atmosphere || media type="custom" key="24155626" Agriculture and the atmosphere || media type="custom" key="24155672" Energy production and the atmosphere ||
 * media type="custom" key="24155548"

5 Impacts on the Environment || media type="custom" key="24192398" Pollution ||
 * media type="custom" key="24192156"


 * Common misconceptions:**
 * Only humans produce greenhouse gases.
 * Carbon dioxide is the gas that contributes the most to the Greenhouse Effect.
 * The rate of change in the composition of the atmosphere hasn't really changed that much in the last 200 years.
 * Oxygen is the main component of the Earth's atmosphere.
 * Most plants can use atmospheric nitrogen.
 * Human activities have not affected the atmosphere's composition.


 * Interesting facts:**
 * Without an atmosphere/greenhouse gases, day-time temperatures would be around 100 C and night-time temperatures would be lower than -150 C. The average temperature on Earth would drop from 16 C to -18 C**.**
 * Water vapour contributes more to the Greenhouse Effect than any other gas.
 * The composition of the atmosphere has changed dramatically over the last 200 years because of human activity, including:
 * Clearing of forests for agriculture (reducing carbon dioxide intake via photosynthesis)
 * Burning of coal to produce electricity (which releases carbon dioxide and sulfur dioxide into the atmosphere)
 * Using fossil fuels in transport (petrol and diesel)
 * Using propellants in aerosols and foaming agents (change the balance of atmospheric gases).
 * Nitrogen gas makes of 78% of the atmosphere, oxygen is at 21%.
 * Animals and most plants need microorganisms to convert atmospheric nitrogen into a usable form.


 * Resources:**
 * Earth's atmosphere from The University of Illinois Department of Atmospheric Sciences.
 * Forces of Change (atmosphere) from Smithsonian National Museum of Natural History.