All matter is part of a material pathway and the composition of matter on the earth reflects the movement of various materials through these pathways

Weather as a Feedback Loop

Unequal distribution of radiation due to earth axis tilt is the ultimate driver of the weather. ( go here for a more detailed explanantion )

Heat, energy flow is generally from the equatorial regions to the polar regions.

Rotation of the earth sets up large scale circulation cells called Hadley Cells As well as Rossby Waves . Forecasters try to determine the short term behavior of these Rossby Waves

High and low pressure systems then ride these waves through the jet stream and that trajectory (1.1 JDK applet) determines the kind of weather that say, Oregon, gets.

Ocean currents and temperature influence the temperature of the air and hence its capacity to hold moisture. This is why El Nino can effect the world wide weather. Alteration of normal sea surface temperatures feed back to the weather.

Changing the outgoing radiation balance of the earth also leads to climate change - this is the greenhouse effect which we will discuss in detail later

Large Scale climate is set up by the constant exchange of moisture and energy between the ocean and the circulating atmosphere. These determines large scale pattern of High and Low pressure areas . Circulation around a Low Pressure system is counterclockwise in the Northern Hemipshere. Circulation around a High Pressure system is clockwise in the Northern Hemipshere.

• Why it rains here in winter
• Why it doesn't rain here in summer
• Cool in Summer or Snow in Winter

• If the high slides further east and can generate downslope winds it gets real hot in the Valley

Pacific Coast Pacific Maritime Climate Cold Current, strong ON shore flow of dry air in the Summer no humidity!

East Coast Warm current, lots of moisture, Bermuda High brings it a shore -summers suck!

Let's see the Movie which shows the seasonal evolution of these currents

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Good Summary Lecture on Atmospheric Circulation

Summary of El Nino phenomena

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