Apologia Physical Science Module 7 Study Guide

Define aphelion.

The point at which the earth is farthest from the sun

Define perihelion.

The point at which the earth is closest to the sun

Define lines of longitude.

Imaginary lines that run north and south across the earth

Define lines of latitude.

Imaginary lines that run east and west across the earth

Define Coriolis effect.

The way in which the rotation of the earth bends the path of winds, sea currents, and objects that fly through different latitudes

Define air mass.

A large body of air with relatively uniform pressure, temperature, and humidity

Define weather front.

A boundary between two air masses

What is the difference between weather and climate?

Weather changes from day to day while climate does not.

What are the three main factors that effect earth's weather?

Thermal energy, uneven distribution of thermal energy, and water vapor in the atmosphere

Be sure that you can identify each of the cloud types in Figure 7.1.

If stratus clouds are dark, what are they called?

Nimbostratus, WHen a cloud is dark, you add a suffix of "nimbus" or prefix of "nimbo".

If you find lenticular clouds higher than normal, what are they called?

Altolenticular, when a clouds is higher than usual, you add the "alto" prefix.

What does "insolation" stand for?

Incoming solar radiation

In the Northern Hemisphere, is the length of the days greater than or less than 12 hours between June 21 and September 22? Are the day lengths increasing or decreasing during that time?

The days are greater than 12 hours long, but are decreasing in length. In the Northern Hemisphere, June 21 is the summer solstice. That's when the days in the Northern Hemisphere are at their longest, becasue the Northern Hemisphere is pointed towards the sun. They then begin to decrease so that by September 22 (the autumnal equinox), they are exactly 12 hours long.

In the Southern Hemisphere, between what dates are the day lengths less than 12 hours but increasing?

From June 21 to September 22, in the Southern Hemisphere, the days get longer from June 21 (the Northern Hemisphere's summer solstice) to December 21 ( the Northern Hemisphere's winter solstice). On September 22 (the Northern Hemisphere's autumnal equinox), They are exactly 12 hours long. Thus, from June 21 to September 22, the days get longer, but are still under 12 hours.

Is the Northern Hemisphere's summer during aphelion or perihelion?

The Northern Hemisphere is pointed toward the sun at aphelion, so that's when it's summer in that hemisphere.

What causes wind?

Temperature differences

Why isn't there a constant stream of wind blowing from the poles to the equator?

There isn't a steady stream of wind blowing from the poles to the equator because the temperature of the air changes as it changes latitude. This causes loops of wind to develop at different latitudes.

What causes the wind patterns to bend in different regions of the globe?

The coriolis effect

Suppose you are in Alaska and would like to fire a missile to hit a target at the equator, due south of your location. Ignoring the effects of wind and air resistance, in which direction should you aim the missile?

Southeast, the ground in Alaska rotates slowly compared to the ground at the equator. Thus, as the missile travels, the ground underneath it will outrun it. As a result, the missile's path will bend to the west relative to the ground. To correct this, you will have to fire the missile southeast.

At nighttime, high elevations usually cool faster than low elevations. Thus, at night, the land on a mountain is usually cooler than the land in the valley next to the mountain. Will the local wind produced by this effect blow from the mountain into the valley or from the valley up to the mountain?

At the surface of the earth, winds blow from cold to warm. Thus, the wind will blow from the mountain to the valley.

Is the humidity high or low in a continental polar air mass? Is this air mass warm or cold?

Since it is continental, the humidity is low. Since it is polar, the air mass is cold.

Is the humidity high or low in a maritime tropical air mass? Is this air mass warm or cold?

Since it is maritime, the humidity is high. Since it is tropical, the air mass is warm.

Over a period of a few days, you notice cirrus clouds forming, followed by stratus and nimbostratus clouds. In just a few hours, however, dark cumulonimbus clouds form, heralding a thunderstorm. What kind of front caused this?

Occluded front

In less than a day, dark cumulonimbus clouds form and unleash a thunderstorm that lasts only a few hours. After the thunderstorm is over and the sky clears, do you expect cooler or warmer temperatures as compared to the temperature before the clouds began forming?

This kind of pattern and the resulting rain is indicative of a cold front. Thus, you should expect cooler temperatures.

Over a period of a couple of days, the clouds slowly build, and then a gentle, long rain ensues that lasts about 20 hours. What kind of front causes this weather?

This kind of weather is indicative of a warm front. It is not a stationary front because the rain would have lasted several days.