Slide 1

Heating the Atmosphere Radiation Conduction The Earth receives its energy from the sun through radiation The transfer of energy as electromagnetic waves. Energy absorbed by a surface heats Example: Your skin feels the sun as it absorbs the energy & warms The transfer of thermal energy from one material to another by direct contact Always moves from the hotter to the colder Example: your feet touching hot sand

Slide 2

Convection Greenhouse Effect The transfer of thermal energy by the circulation or movement of a liquid or gas Heated = less dense, rises Cools = more dense, sinks Called convection current Example: heating your home, boiling rice http://sol.sci.uop.edu/~jfalward/heattransfer/heattransfer.html The Earths heating process, in which the gases in the atmosphere trap thermal energy. CO 2, water vapor keep energy from leaving atmosphere Similar to a blanket keeping you warm

Slide 3

Radiation Balance Is it really a problem? The balance between incoming and outgoing energy If CO 2 & other greenhouse gases increase, the balance could be affected Temperatures rise, changing plant & animal environments Some scientists believe there is a natural warming & cooling process for the Earth. They feel this current warming trend is not a problem Studies show that while there is a natural warming & cooling for the earth, the current one is greater than ever before Many nations (not the US), have signed the Kyoto Agreement to help reduce Greenhouse gases

Slide 4

Kyoto Agreement Countries