Last Class – Global What transformations occur as energy flows through theearth system.

Relationship between distance from the source and amountof energy available.

This Class - Energy Balance – Earth’s Structure How does variability in the earth’s physical structure affect the transformations of energy?

What is the physical structure of the atmosphere?

What is the chemical structure of the atmosphere?

Energy comes to earth in thesewavelengths

Energy leaves the earth in thesewavelengths

How do features of the earth’s surface control energy exchange - Changes in Albedo

How features of the earth’s surface control energy exchangeChanges in Albedo

Light colors reflect energy – they have a high albedo(e.g. snow, ice)

Dark colors absorb energy – they have a low albedo(many soils and rocks)

Water can be quite variable in it’s albedo(related to angle of incidence and what is in the water)

Effect of Clouds on RadiationDaytime

Clear sky conditions Cloudy conditions

Effect of Clouds on IR RadiationNight time

Clear sky conditions Cloudy conditions

Ahrens 3rd Edition, p. 63

Energy Balance – Atmospheric Structure - Feedbacks

What is the physical structure of the atmosphere?

What is the chemical structure of the atmosphere?

These fluxes are related to the structure and composition of the atmosphere. They allow life to exist

Weather occurs here

Ozone - UV protection here

Structure of the Atmosphere

Thermosphere

Mesosphere

Ozone MaximumStratosphere

Troposphere

Temperature

78% nitrogen

20.6% oxygen

< 1% argon

0.4% water vapor

0.036% carbon dioxide

traces gases:Ne, He, Kr, H, O3

Methane, Nitrous Oxide

Absorption Spectra of Atmospheric Gases

Anthes, p. 55

WAVELENGTH (micrometers)

Energy Balance – Atmospheric Structure - Feedbacks

What is the physical structure of the atmosphere?

- multi-layered, with little chemical interaction- most of the mass is near the surface

What is the chemical structure of the atmosphere?

- nitrogen by far the most common element- oxygen is second most common- greenhouse gasses are small in amount, but important!

Absorption Spectra of Atmospheric Gases

Anthes, p. 55

WAVELENGTH (micrometers)

http://www.ems.psu.edu./Courses/earth002/0402G_M.htm

Global Water Balance

100217913

87

8

Anthes, p. 47 (modified)

Earth’s annual water balance, (original) units are 105 km3 of water per year. Huge quantities of water are cycled through the atmosphere each year. On the continents, precipitation exceeds evaporation and the reverse is true for oceans. Runoff from the continents balances the deficit of the oceans.

Land Ocean

Precipitation Precipitation

Evaporation

Runoff

Since the amount of energy comingfrom the sun varies on long andpredictable time scales, we need to focuson the exchanges

1) In the atmosphere, and

2) At the earth surface