THE FATE OF THE FATE OF INCOMING SOLAR INCOMING SOLAR

RADIATIONRADIATIONChapter 23.2Chapter 23.2

What can happen to a sun ray What can happen to a sun ray when it enters the atmosphere?when it enters the atmosphere?

• Reflection (30%) • By Clouds

• By dust particles

• By the Surface– Light colored surfaces reflect more– Amount of reflection is called albedo

AlbedoAlbedoPAGE 465PAGE 465

What can happen to a sun ray What can happen to a sun ray when it enters the atmosphere?when it enters the atmosphere?

•Absorption (70%)• Clouds and atmosphere (20%)

–Short waves are absorbed in meso and thermospheres by N2 and O2

• Surface (50%)–Dark surfaces absorb more

ScatteringScattering

• Water and dust in atm. Bend sun rays

• Makes the sky blue

• sunsets

Average distribution of Average distribution of incoming solar radiationincoming solar radiation

What affects a climate’s What affects a climate’s temperature?temperature?

a. Latitude

closer to equator =warmer

closer to poles= colder

b. b. AltitudeAltitude

high altitudes =

___ temperatures

low altitudes =

___ temperatures

Water VaporWater VaporIf a desert and a rain forest are the

same temperature

during the day, would they be the

same temperature at night? Why or

why not?

c. Water Vaporc. Water Vapor

• Water vapor traps heat in the atmosphere..

At night, which is cooler—the At night, which is cooler—the land or the water?land or the water?

At night, the water is warmer than the land!

http://www.cs.indiana.edu/~nigupta/Beach-at-night.jpg

d. Coastlines vs. inlandd. Coastlines vs. inland

• Land heats up and cools off much more quickly than the water.

• Coastal= maritime

• inland= continental

Given that, why can we drive down Lake Shore Drive on a

warm spring day and see giant ice sheets on the lake?

World mean sea-level World mean sea-level temperatures in Januarytemperatures in January

Which affect most Which affect most influences temperatureinfluences temperature

latitudelatitude

ConductionConduction

• Molecules touch each other and transfer heat

CONVECTIONCONVECTION

• Transfer of heat by circulation within a substance

• Heat rises

RADIATIONRADIATION

• Transfer of energy (heat) through space by EM waves

• Sun’s energy reaching earth

Mechanisms of heat transferMechanisms of heat transfer