2. 1. Where does weather
come from?
Weather ultimately
begins with the
ocean. In fact, even a small change
in ocean temperature can affect
weather patterns
around the world.
3. When the sun’s rays
warm the surface of the earth, the
atmosphere is warmed as well. The
warm air produced moves over
warm water and evaporation
occurs.
4. Saturated with water
vapor, the warm air rises
Into higher, colder altitudes and
over highlands. When the warm,
moist air mass cools, the water
vapor inside condenses and falls as
rain.
3
Click the cloud!
5. 1. Ocean currents happen because of the special properties of water. Cold
water is denser and sinks; warm is lighter and rinses.
2. Warmer water from the oceans around the equator rises to the top, while
colder water from the oceans around the poles sinks to the bottom.
3. The water from the poles travels to the equator, and the water from the
equator travels to the poles.
Ocean Currents
6. The Gulf Stream
The Gulf Stream is a
powerful current that originates from the tip
of Florida. It affects weather in my home
state, New Jersey, bringing warm
temperatures and high humidity from its
origin in the tropics.
7. The movement and temperature of ocean currents
influence the movement and temperature of marine air
masses.
Ocean Currents and Air Masses
Ocean Currents Air Masses
8. Air Masses
When two air masses collide, the differences in
temperature, humidity and pressure create
various kinds of weather.
The line at which two air masses collide is
called a front. Along the front, the collision of
two air masses can produce rain, hail, wind,
lightning and thunderstorms, including
hurricanes and tornados.
9. Polar Weather
Since Antarctica is a landmass, it doesn’t receive
much heat from the ocean. On the other hand, the
Arctic, because it is just an icy covering, has the
ocean under it to warm it.
Antarctica The Arctic
Average temperature Average temperature
Winter -76°F; Summer -18°F Winter -40°F; Summer 32°F
The Ocean’s Effect
10. The Intertropical Convergence Zone is the
line at which north winds meet south winds.
The result is heavy precipitation, as seen
by the chart below.
Tropical Weather
