Earth 002

Tuesday, February 2nd, 1999
Announcements:

Lecture notes:
DISTRIBUTION OF ENERGY WITH RESPECT TO LATITUDE

• The distribution of energy over the earth varies from place to place.

• When solar rays hit the earth at an angle, the amount of energy received is twice as great as when it hits the earth straight on
• This explains why the North and South Poles receive so much less energy than the Tropics

HEAT TRANSFER

• Heat Capacity-the amount of energy it takes to change something's temperature (ex. oceans have a very high heat capacity, land has almost none)

• There are a wide variety of energy imbalances at different areas on earth--Tropical Rainforests receive 93%, Oceans get 93%-50%, and the Desert gets 75%

HEAT TRANSFER MECHANISMS

• Radiation--heat radiates into the earth either through its interior or the sun
• Conduction--molecules bumping together and transferring heat
• Convection--vertical motions
• Advection--horizontal motions
• Phase Changes--water evaporates-->water vapor-->water condenses-->LATENT HEAT TRANSPORT

ATMOSPHERE CIRCULATION

• Atmospheric Circulation results from the system trying to compensate for the energy imbalance
• Heat Air Parcel--heated air is more bouyant than descending air

CORIOLIS EFFECT

• Angular Rotation at the equator is greater than the angular rotation at the North Pole, which causes curved air parcels
• Because of these curved air parcels, there is no way for a polar moving air parcel to make one complete circle
• The angular rotation of earth forces separate cells of circulation

PRESSURE REGIONS

Pressure regions are defined by the need to get rid of energy imbalance

PRECIPITATION

MONSOONS

The oceans absorbs lots of energy and heats slowly while the land absorbs varied amounts of energy and heats up slowly

Air then comes offshore, uplifts, and causes rain

It is called a monsoon whenever air heats up, uplifts the rising ocean air, that air cools off and then very large amounts of rain are produced

GENERAL CIRCULATION

The general circulation is the large scale circulation of the features of our atmosphere

Energy Balance-governs what we live with

Mass Balance-we must keep track of where air parcels move & move them back

Angular Momentum Balance-some winds go with the rotation of the earth, others go against it...they must be balanced