Chapter 6
Which surface has a higher albedo: ice, ocean water, land?
Ice
Convection cell
A circular moving loop of matter involved in convective movement.
How and why does density of air or water change in a convection cell?
A column of cool, dense air causes high pressure at the surface, which will lead to sinking air (movement toward the surface and compression). A column of warm, less dense air causes low pressure at the surface, which will lead to rising air (movement away from the surface and expansion).
How does the Coriolis effect influence the movement of air in atmospheric circulation cells?
A large circuit of air is called an atmospheric circulation cell. Three cells exist in each hemisphere. 1. hadley cells are tropical cells found on each side of the equator. 2. ferrel cells are found at the mid-latitudes. 3. polar cells are found near the poles.
Coriolis Effect
An apparent force resulting from Earth's rotation causes particles in motion to be deflected to the right in the Northern Hemisphere to the left in the Southern Hemisphere.
What direction does the Coriolis Effect cause objects to move in the Northern and Southern hemispheres?
As air warms, expands, and rises at the equator, it moves toward the pole, but instead of traveling in a straight path, the air is deflected eastward. In the Northern Hemisphere air turns to the right. In the Southern Hemisphere air turns to the left.
Why doesn't the ocean boil at the equator?
Because heat is transferred by winds and ocean currents from equatorial to polar regions.
How does incoming solar radiation vary with latitude? Why?
Depending on the latitude, the intensity of the Sun's solar intensity is different. For example, at the poles, there is a low angle of solar intensity, and that solar intensity is spread across a wider area. However, at the equator, there is a high angle of intensity, and that solar intensity is spread across a smaller area.
What are greenhouse gases?
Gases in the atmosphere that trap the energy emitted by the warm surface of the earth (carbon dioxide is an example).
How does the global heat balance change with latitude? Why?
Low latitude regions receive more solar radiation than high latitude regions, but oceanic and atmospheric circulation transfer heat around the globe.
How does the reflectivity of the Earth's surface affect the amount of heat?
The albedo of various Earth materials is the percentage of incident radiation that is reflected back to space. More radiation is reflected back to space at high latitudes because ice has a much higher albedo than soil, vegetation, or water. the angle at which sunlight strikes the ocean surface determines how much is absorbed and reflected. The ocean reflects more radiation at high latitudes than at low latitudes. Because of all these reasons, the intensity of radiation at high latitudes is greatly decreased compared with the intensity of radiation received in equatorial regions.
Heat capacity
The amount of heat energy required to rase the temperature of a substance by 1 degree C.
ITCZ (Intertropical Convergence Zone)
The boundary between the two trade wind belts along the equator is known as the doldrums because, long ago, sailing ships were becalmed there by the lack of winds. It is the region between the tropics where the Northern and Southern Hemisphere trade winds converge.
What is the composition of the atmosphere?
The composition of the atmosphere is almost entirely nitrogen and oxygen. Other gases include argon and carbon dioxide, as well as others in trace amounts.
Albedo
The fraction of incident electromagnetic radiation reflected by a surface.
How does a convection cell work?
The hotter lower density liquids moves to the top of the mass, then as it cools down moves to the bottom, then repeats.
Ocean circulation
The large scale movement of waters in the ocean basins. Winds drive surface circulation, and the cooling and sinking of waters in the polar regions drive deep circulation.
Where do the major deserts of the world form? Why?
They lie in the so-called Horse Latitudes, where constant high-pressure systems drive away the rain clouds, and swirl above the earth to the music of global temperature variations and the Coriolis Effect produced by the earth's rotation in space.
Atmospheric circulation
This process redistributes heat towards the poles, shapes the broad patterns or moisture transport, and influences surface ocean currents.
What factors govern the global circulation of air?
Uneven solar heating and The Coriolis effect.
Global wind patterns
Winds are caused by differences in highs and lows. the trade winds will bend to the right in the N hemisphere and the left in the S hemisphere. Winds are named for where they come from thus the trade winds are easterlies.
Which has a higher heat capacity, ocean water or land?
ocean water