Download File - OTHS Aquatic Science

Intro to Weather Clip
Weather by Brainpop
1) What cycle is the basis of our weather?
2) What causes precipitation to occur?
3) Where do storms usually occur?
Weather

Temporary behavior of atmosphere (what’s going on at
any certain time)

Small geographic area

Can change rapidly
Weather
--The study of weather is meteorology
--Someone who studies weather is called a
meteorologist
Climate



Long-term behavior of atmosphere (100+ years)
Large geographic area
Very slow to change
POLAR
90o -60o latitude
Cool summers, cold year-round
Dry
TEMPERATE
60o-30o latitude
True Seasons
Variety of climate patterns
Moderate precipitation (rain/snow)
TROPICAL
30o - equator
No winter, warm year-round
High temp, rainfall, humidity
Climate Types by Brainpop
1.What is climate?
2.Where are tropical climates most likely
to be?
3.What does “arid” mean?
What Factors Affect Weather & Climate?
1.
2.
3.
4.
The Sun
The Water Cycle
The Atmosphere
The Ocean
How Does the Sun Affect Weather?
It warms the atmosphere & oceans
It creates climate zones
It keeps the water cycle going
It affects weather patterns
The Water Cycle
All the water on the planet is recycled in this manner!
Parts of the Cycle
Evaporation—Water going from a liquid to a
gas (gains energy from the sun)
Parts of the Cycle
*Transpiration—evaporation of water from/out of
plants. Locate this on the diagram!
transpiration
Parts of the Cycle
Condensation—Water going from a gas to a liquid (cools or
loses energy)

When this happens in the atmosphere, CLOUDS form.
Parts of the Cycle
Precipitation—when water falls out the atmosphere.
Forms when the water droplets in clouds become too
heavy to stay up.
Precipitation
Liquid water = rain

Rain Clip
Frozen water = snow or sleet or
hail

The Water Cycle
Water Cycle by Brainpop
Water Cycle Advanced by Brainpop
How does the atmosphere affect
weather?
The atmosphere is a mixture of gases that
surrounds the Earth
Has five different layers; each has different
properties
We’ll label them in just a minute…
Air Temperature and Pressure change with
altitude
Weather occurs in the layer closest to Earth
Earth’s Atmsophere by Brainpop
1. What is ozone?
2. What layer of the atmosphere does
weather occur in?
3. What 2 gases compose the most of
Earth’s Atmosphere?
Air Masses
= body of air with a certain
temperature and moisture level
Can be warm or cold
Can contain a lot of moisture or not a
lot of moisture
Fronts
= places where air
masses meet
4 Types: Warm, Cold,
Occluded, Stationary
Each kind can bring
different kinds of
weather
Occluded Front:
Stationary Front:
Science Saurus 221/222
& Reading a Weather
Map Worksheet
How does Air Pressure affect
weather?
How much the earth’s atmosphere is pressing down on us
Measured with a BAROMETER
If it CHANGES, then new weather is on the way:
Falling Air Pressure = stormy weather coming
Rising Air Pressure = fair weather coming
Steady Air Pressure = no change is coming
Winds = created from differences in air
pressure
Moves from areas of HIGH to LOW pressure
Greater the difference in pressure, the FASTER the wind
blows
Measured with wind vanes and anemometers or you
can estimate with the Beaufort Wind Scale
ScienceSaurus 224/225
Beaufort Wind Scale
Global Winds
Thousands of kilometers long; can cause
weather to move in different directions
Jet stream, prevailing westerlies, doldrums,
horse latitudes, trade winds
Big Winds Blowin’ Worksheet &
Science Saurus Section 217
Global Winds
Caused by the temperature difference in
different regions
Hot Tropical Regions—causes air to rise
 Cold polar Regions—causes air to sink

Global Winds
Also affected by Earth’s Spin

Coriolis Effect = causes winds to curve to the right
in the N. Hemisphere; to the left in the S.
Hemisphere
Big Winds Blowin’ Worksheet
Relative Humidity

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

Measure of the amount of moisture in the air
compared to what the air could hold
How “full” of water the air is
Expressed as %
100% relative humidity = saturated air
Relative Humidity Test Applet
http://itg1.meteor.wisc.edu/wxwise/relhum/rhac.html
Relative Humidity
Controlled by temperature
1. Warm air holds more moisture than cool air (more
space for water vapor between air molecules)
2. As air warms, relative humidity decreases
3. As air cools, relative humidity increases
Dew Point

=Temperature at which the air is saturated (100%
relative humidity)
Several events can occur when the dew point temp. is
reached:
1. If dew point temp. is above freezing:
a. water vapor condenses as liquid
b. dew will form on surfaces
Dew Point
c. cloud droplets will form in air
2. If dew point temp. is below freezing:
a. water vapor condenses as a solid
b. frost on surfaces
c. snow (or hail) in the air
Humidity by Brainpop
1. What single factor controls humidity?
2. What temperature air can hold the most
water molecules?
3. What causes water to evaporate into the
atmosphere?
Rainbow by Brainpop
How does the Ocean affect weather?
Ocean currents affect the temperature of the land they
pass by
Cold ocean currents = cooling effect
Warm ocean currents = warming effect
Temperature changes affect pressure – which then creates
WINDS
Winds blow this cooling or warming effect over the land
http://earth.rice.edu/MTPE/hydro/hydrosphere/topics/Ocean_Atm_Circ_ElNino.mov
http://www.wunderground.com/MAR/
Science Saurus Sections 203-204-205-206