Earth Science - Chapter 16

Force exerted by the weight of overlying air

decreases with altitude
rapidly at first, then more slowly

millibar, pascal, inches of mercury

Solar radiation not evenly distributed over the earth's surface

unequal heating
drives ocean currents
creates winds

heat is transported from the equator to the poles

Defined by dates on which the earth reaches ceratain points in its orbit about the sun

periods of greatest and least insolation are centered about the solstices

warmest and coldest periods do not coincide with the seasons - only match approximately!

earth closest to sun in jan
fathers from sun in july

Heat - form of kinetic energy
extensive - depends on the amount of matter

temperature - measure of the hotness or coldness of an object
measure of average kinetic energy (heat) contained atoms or molecules of an object
intensive - depends on amt. of matter

Conduction
convection
radiation

Heat transfer through matter by molecular activity

requires physical contact for flow of heat from region of high temperature to region of low temperature

not particularly important to heat transport in the atmosphere
(air is a poor thermal conductor)

Transfer of heat by mass movement or fluid flow

Fraction of total radiation reflected by a surface

varies due to thickness of clouds,
particulate matter in the air,
angle of sun's rays to the earth's surface,
nature of surface material

A black body is a theoretical object that absorbs 100% of the radiation that hits it.
Therefore it reflects no radiation and appears perfectly black.

Incoming radiation (mostly visible light) is absorbed by land and water, and then reradiated as IR radiation

certain gases absorb reradiated IR radiation

causing an increase in the atmospheric temperature

Gases that absorb reradiated IR radiation

CO2
Methane
Chlorofluorocarbons (CFCs)
Nitrous Oxide
ozone

Average of maximum and minimum temperature

Difference between the maximum and minimum temperature

Average of hthe daily mean temperatures

Average of the monthly mean temperature over a year