CH.7.LES.1
The Atmosphere and Weather
I. How Does the Sun Warm the Earth?
A. Temperature depends a lot on the angle at which _________hits a region.
B. The areas around the equator are the__________. Why?
1. In these areas the Sun’s path is ________overhead at midday.
2. The Sun’s rays hit Earth at their________________.
C. The areas around the North and South Poles are the____________. Why?
1. Here the Sun is much ___________at midday.
2. The Sun’s rays hit the Earth’s surface at a ______angle and are
spread out over a greater area.
3. The strength or the rays is much _____________at this angle.
D. The angle at which sunlight strikes the Earth’s surface is called
the__________ _____ _____________.
1. Insolation is__________ _________ _______________.
2. This is the amount of _______ _________that reaches Earth
at a given place and time.
3. The greater the angle, the _______________it gets.
4. The angle of insolation is always _____________near the
equator than at the poles.
II. What are the layers of the atmosphere?
A. The ______________is the lowest layer of Earth’s atmosphere and
contains most of the air in the atmosphere.
1. All life on Earth exists here.
2. All_______________, rain, clouds, snow, and thunderstorms form in
this layer.
A. Air temperatures drop as you go higher up a mountain because you are
traveling higher above sea level.
B. Temperatures drop about _______________for every 305 meters/ 1,000
feet in altitude.
C. ________________is the condition of the troposphere at any given time
and place.
1. The conditions that make up weather are air temperature, air pressure,
amount of moisture in the air, wind, clouds, and rain or snow.
III. What Happens to the Air Pressure?
A. Air is made up mostly of molecules of _________and_____________.
B. These air particles press on Earth’s surface and on everything they surround.
C. _______ ______________is the force put on a given area by the weight
of the air above it.
As you go higher in altitude, air pressure steadily______________.
D. Normal air pressure is greatest at_________________. Sea level air
pressure is about 1.04 kg per square centimeter (14.7 lbs. per square inch).
E. As you go higher in altitude, the height of the air column above you
becomes____________. Therefore the weight of that column – or air
pressure- becomes______________.
F. In the lower atmosphere, the composition of air is mostly the same. Up to an
altitude of 100km (62 miles), air consists of a mixture of__________, water
vapor, and dust particles.
1. Nitrogen and oxygen make up ___________of the gases in dry air.
(78%Nitrogen and 21% Oxygen)