The Climate System

GEOL 3100

Earth’s Climate and Environment:

Past, Present, and Future

Uneven deliveryof Sun’s heat toEarth

Uneven reflection ofSolar radiation onEarth’s surface

What is the definition ofAlbedo?

The percentage ofincoming radiationreflected by asurface

Albedo = = reflectivity

Greenhouse EffectA. Why don’t

the red arrows add up?

B. Without the GH effect, what would Earth’s avg. T be?

C. What are the main GH gases?

D. Do clouds trap or reflect heat?

A) Multiple absorption/radiation cycles, B) -16 C, C) H20 1-3%, CO2 0.035%, D) both

Uneven heatingof Earth’ssurface provideskey to understandingEarth’s weatherand climate

Heat deliveredvaries with1) Latitude

2) Season

Incoming Solar Radiation (Short Wave)

Heat reflected varies with season

Heat absorbedvaries with surface

Outgoing Radiation (Long Wave)

Incoming, Outgoing and Net Radiation

Given theobservedvariations indelivery and reflection of solar radiation,does the variation in thelatitudinal temperatureprofile seem too big or too small?

Incoming, Outgoing and Net Radiation

Mechanisms of heat transfer in the atmosphere

• Conduction– Moves sensible heat through diffusion

• Convection– Moves sensible heat through movement of air– Moves latent heat through movement of water

• Average parcel of water travels 1000 km (LA to Denver)

Convection Cell

Is this the summer or winter monsoon?

Why do pollutants accumulateat high latitudes?

80% of atm

99.9% of atm

Miles

31

11

5

Feet

164K

60K

26.4K

If the Earthwas thesize of abasketball,how thickwould theatmospherebe?

a fruitroll-up

•Where is most of the latent heat in the atmosphere stored?•How far does the average parcel of water vapor travel?

Water vapor feedback

• Activity:– Work with your

neighbor to list the four steps of the water vapor feedback

• Does this feedback include clouds and the effects of latent heat?

•What hemisphere is this?•How do you know?•How many of you have studied the Coriolis effect?

Eckman Spiral

1000 m/hr!!

Activity:Plot the path of a parcel of air traveling 20 mph from 30N towards the equator, marking the progress each hour for 5 hoursPlot the amount of rotation of the earth for each of these points during that hour assuming that the Earth is rotating 800 mphDoes the atmosphere rotate with the Earth?If the atmosphere couldn’t quite keep up with the Earth, how would the air appear to move from the Earth’s surface

Water piles up2 m higher!

Circulation PenetratesTo 600-1000 mdeep

Surface ocean circulation

Where are the boundary currents?

Oceanic circulation and climate

• Water has a high heat capacity

• One third of the Earth’s heat transport from the equator toward the poles is transported by the ocean!

• Without the Gulf Stream current, Europe would be 10 – 20 °F colder

What drives ocean circulation?

• Like in the atmosphere, density differences

• What changes the density of water?– Temperature: colder water is more dense– Salinity: saltier water is more dense

The Gulf Stream Current• What causes the

surface ocean water to move?

• What happens to the water as it goes through the Caribbean and past Florida?

• What happens to the water as it goes towards Greenland?

• Where is most of the ocean’s deep water formed?

Thermohaline circulation

Which is the densest ocean water mass?

If water goes into the deep ocean in the high latitudes, where does it come back up?

Are Duluth winters colder or warmer if the lake freezes over?

Equilibrium line

Mean annual T at Equil. line mtn glaciers = 0 CMean annual T at Equil. line ice sheets = -10 C

What is an ice stream?

What is the best place to core an ice sheet?

What proportion of the atmosphere, vegetation, deep ocean, and rock record exchange each year? Quickest and slowest to change?

Which biome has the highest albedo?Which biome has the lowest albedo?

Where do you see theeffect of vegetation on The carbon cycle?