Chapter 1, "What Causes Weather Patterns?," introduces
students to some of the important science concepts that
influence the weather. The activities in this chapter provide
students with information about how the Sun, water, and wind
interact to cause various weather patterns.
In the Engage activity, Water on the
Move, students will conduct a hands-on investigation to
stimulate their thinking about water in the atmosphere. They
then will view a demonstration to further stimulate their
thinking about the phenomena of evaporation and condensation
(although the terms will be formally introduced in the Explain
activity).
The Explore activity, Wind in a Box,
focuses on air movements. Students will use convection boxes to
model air movements in the atmosphere.
The Explain activity, Weather and the
Movements of Water and Air in the Atmosphere, provides the
information that will help students connect their findings from
the Engage and Explore activities to science concepts. Students
will learn how the water cycle, air pressure, density, and
temperature affect movements in the atmosphere and, in turn, how
these factors interact to cause different weather patterns.
In the Elaborate activity, Winds above
a Rotating Earth, students will build on their understanding of
air movements in the atmosphere. They will begin the activity by
using a hands-on model to investigate the effects of Earth’s
rotation on wind direction. They will also work through a
simulation to learn about the Coriolis effect, the apparent
change in direction of an object due to Earth’s rotation. In
an optional sidebar, students will learn more about the Coriolis
effect through analysis of a Foucault pendulum, a technology
that provided some of the first evidence for Earth’s rotation.
Finally, in the Evaluate activity, Patterns
Help Us Understand Weather, students will use what they have
learned about air movements in the atmosphere to analyze weather
fronts. They will also explain how patterns of water and air
movements can be used to predict future weather events.
Students may harbor misconceptions about the material they
will be studying in this chapter. Some of these misconceptions
are listed in this section (American Association for the
Advancement of Science, 2001; Driver, Squires, Rushworth, &
Wood-Robinson, 1994). Do not take time to go through them as a
list of lecture topics for your students, but rather use them to
inform your teaching as they emerge. Many activities included in
this chapter work to expose misconceptions and help students
develop better mental models.
Some common misconceptions include:
- Air does not have weight. Recognizing that air
has weight may be challenging even for high school students.
- Air exerts force or pressure only when it is
moving, and only downward. Students may not recognize that
forces in air are transmitted in all directions.
- Wind causes the movement of visible objects
such as clouds, tides, and waves. Few middle school students
understand that pressure differences between regions of the
atmosphere cause the air movements we call wind.
- Wind speed is related to temperature
differences between areas of air. High-speed winds are cold
and slower; gentle winds are warmer.
- Cold causes hydrogen and oxygen to change into
water or to form water. Water exists in one of three states:
solid, liquid, or gas. A water molecule consists of two atoms
of hydrogen and one atom of oxygen in all these states.
For several of the activities in the chapter, you will
need only 24 hours of advance notice for preparations. Other
activities are likely to require additional time:
- Engage: Water on the Move—for collection of materials
and preparation of the demonstration setup
- Explore: Wind in a Box—for collection of materials
and preparation of convection boxes
- Explain: Weather and the Movements of Water and Air in
the Atmosphere—for preparation of the demonstration setup
- Elaborate: Winds above a Rotating Earth—for
collection of materials
See the Advance Preparation sections of these activities
for details on the necessary preparations.
