unit 9: climate & meteorology -...

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Vocabulary

Earth’s Energy

n Energy from the

Through the seasons, it heats our world, some parts more and some less

Solar Electromagnetic Spectrum

The includes visible light, as well as X-rays,

ultraviolet rays and infrared rays.

Climate Climate is .

• – a system of accounting for moisture income,

storage, and outgo for the soil in a specific area.

Unit 9: Climate & Meteorology

Weather Temperature Dew Point Relative Humidity Psychrometer Air Pressure Barometer Isobars Wind Anemometer condensation

Sea Breeze Land Breeze Coriolis Effect Condensation Nuclei Deposition Dew Frost Latent Heat Potential Energy Kinetic Energy Heat of Fusion

Heat of Vaporization Specific Heat Conduction Convection Radiation Pressure Belts Convergence Divergence Air Mass Source Region Cyclone

Anticyclone Front Temperature Gradient Pressure Gradient Station Model Synoptic Weather Map Storm Track Hurricane Tornado Sublimation Jet Stream


are those in which

the total amount of

is greater than the total amount of

(Loss of

water to atmosphere)

have significantly more total PE than P

Climate Pattern Factors

Latitude

Most important factor in determining climate, especially temperatures

v As

, yearly

temperature ranges (difference

between highest and lowest

temperature)

.

v Temperature range is the difference between the average HIGH temperature and average

LOW temperature for an area over a year!

Elevation

As elevation , average yearly

temperature .


Large Bodies of Water

Sea or land locations affect temperature ranges. Since

, coastal locations tend to have warmer winters

and cooler summers. (depends on CURRENT!)

Marine Climate

– A climate under the influence of the sea, characterized by

Continental Climate

–climate that is characteristic of the interior of a landmass.

.

Ocean Currents

• The "Global Conveyer Belt" shows how the oceans move energy from the tropics to the poles and

back again in order to moderate Earth's climate. This is accomplished through long-term ocean

circulation.

El Nino

• A resulting from a reversal of the ocean current in the Pacific

which results in .


Orographic Effect

– – Mountains act as barriers to prevailing winds. As the wind

hits the windward side of a mountain,

– – Side of the mountain that is exposed to the

wind.

– – Descending air warms and it holds more

moisture, making it .

Label your diagram according the picture


Wind Belts

Uneven heating of the Earth produces global wind belts and pressure belts. These “pressure belts”

determine the wetness or dryness of a particular location. Low pressure occurs where air is rising and

thus precipitation occurs. High pressure regions are areas that lack rainfall (DRY).

METEOROLOGY

= the condition of the atmospheric variables, such as

temperature, air pressure, wind, and water vapor, at a particular location for a relatively short period of time.

Factors Affecting Insolation –

Direct result of in orbit distribute energy from vertical to

oblique rays

Tilt (inclination) spreads concentration of energy over broader area

Causes of Weather

This causes earth’s atmosphere to react and become a gigantic

engine that produces an infinite variety of .

Weather/Atmospheric Variables

n

n

n Moisture Conditions (Precipitation & Humidity)

n Wind (Speed & Direction)


__________

measures air

pressure

____________

measures amount of water vapor

(relative humidity)

__________

measures air temperature

___________ Measures liquid

precipitation

__________ measures wind

direction

__________

measures wind

speed

Weather

Instruments

Note: In the USA we still use degrees Fahrenheit – the rest of the world

measures in oCelsius. If you need to convert……USE THE CHART!


Atmosphere = .

n Composition of the lower atmosphere (troposphere):

1. = 78% used by bacteria in soil to make nitrates

2. = 21% used by plants and animals for respiration

3. = 0.84%

4. = 0.03% used by green plants to make food

5. = 0.01% which include: Helium, Hydrogen, Ozone, Krypton, neon and xenon

6. Also:

Layers of the Atmosphere (Reference Tables)

Watch the Bill Nye Clip about our atmosphere and answer the questions on the following page (4) in your notes.

Bill Nye: Atmosphere

1. Why doesn't the moon have an atmosphere?

2. What is the lowest layer of the atmosphere?

3. What happens to the air pressure as you go up?

4. How much weight does the atmosphere exert on every square centimeter?

5. In a very low place like Death Valley, California (282 feet below sea level), is the air pressure high

or low?

6. What about on top of a mountain?

7. Why is it colder on top of a mountain even though you are closer to the sun?


What is Ozone?

• O3 – we breathe O2

• It occurs naturally in trace amounts in the .

• Ozone protects life on Earth from the Sun’s .

• Ozone is created naturally when sunlight splits apart O2 into single O atoms – these then bond to form more O2 or

O3

What depletes the Ozone?

– chlorofluorocarbons, which are used in:

Atmosphere

and Solar

Energy

Absorbed by Earth’s surface

reflected by clouds

reflected from atmospheric scattering

(aerosols)

Reradiation: Reflected by Earth’s

surface

Absorbed by clouds

Absorbed by atmosphere

Atmosphere and Solar Energy


Greenhouse Effect • Short wave energy comes in and heats the Earth

• As heat reradiates up from the earth, it is emitted in the form of

• The long wave energy becomes trapped by gases in the troposphere

• This trapped gas the air much like your car on a hot day.

Major Greenhouse Gases =


Temperature and Heat

Measuring Temperature

• are lines that connect points of equal temperature. Showing

temperature distribution in this way making patterns easier to see.

Conduction

Radiation

Convection

HEAT TRANSFER


Draw isotherms on the map above, complete the questions below!

1. Lines connecting points of the same temperature are known as…..

2. According to the map above and your ESRT what are the prevailing winds in the USA?

3. As the latitude INCREASES, the temperature generally……

4. Why do the isotherms dip southward in the western part of the USA?

(HINT: What geographic feature makes the winters more cold in that part of the country?)

5. Why should isolines end at the edges of the oceans?

Factors that Effect the Amount/Rate of Heating

vs.

heats up and cools than water

COLOR

vs.

Darker colors tend to absorb more insolation than they reflect.

Surfaces with lighter colors tend to reflect more insolation than they absorb.

TEXTURE


vs.

A surface which has a rough or uneven surface will absorb more insolation.

A surface which is smooth will reflect more than it will absorb

MOISTURE

Changes in State

– The change in state from liquid to a gas, such as liquid

water into water vapor, also called vaporization.

- The changing of a gas or vapor to a liquid.

- Changing of a solid to a liquid

- Changing of a liquid to a solid

Phase Change Diagram


- The change of state from a solid directly to a gas with no

liquid state in between.

Examples: dry ice

– gas changing directly to a solid Ex. Frost

Moisture in the Atmosphere

The primary source of moisture for the atmosphere are the . Other sources include: Lakes, Rivers, streams and transpiration Moisture in the atmosphere exists in all three states/phases.

n – known as water vapor

n – tiny droplets suspended in the air that form clouds

n – tiny crystals suspended in the air that form clouds

is the general term used to describe the amount of water

vapor in the air

determines the amount of water vapor the air can hold.

n As air temperature , the amount of water vapor the air can

hold .

.Saturation –

(Evaporation = Condensation)

• At 350C, a cubic meter of air can hold of water vapor


Factors affecting the rate of evaporation Temperature

Wind

Exposed surface area

Humidity

As humidity goes ____ Evaporation rates go ___________

Temperature

The temperature to which air must be cooled to reach saturation. And Condense…….and make clouds!

• If the air temp drops down to the dew point, condensation will occur. The dew point can tell us how high clouds will form. Clouds form where condensation is occurring.

a. The drier the air, the evaporation will occur resulting in

cooling. In turn, the difference in temperature between the

dry bulb and wet bulb will be .


b. The more humid the air, the evaporation will occur resulting in

cooling of the wet bulb thermometer. In turn, the difference in temperature

between the dry bulb and wet bulb will be .

c. At saturation, the temperature difference between the dry bulb and wet bulb would be

.

RELATIVE HUMIDITY

Maximum amount of water vapor the air can hold at a given temperature.

n The actual amount of water vapor in the air is the .

n tells "how full" the air is with water. It is

expressed in %.

. The ability of air to hold water changes depending on the temperature.

If temperature and moisture in the air remains the same,

relative humidity will .

Changing Absolute Humidity

Temperature

Relative Humidity

If moisture content of the air and temperature ,

relative humidity will .

Using the ESRT to determine Dew Point and Relative Humidity


n Measuring Dew Point Temperature (Dew Point chart)

n Measure the wet-bulb and dry(air) bulb temperatures

n Locate where the air temp crosses the difference between wet and dry bulbs.

n Measuring Relative Humidity (Relative Humidity chart)

n Measure the wet-bulb and dry(air) bulb temperatures

n Locate where the air temp crosses the difference between wet and dry bulbs.

Clouds


Air Pressure

Air pressure acts equally ; it also

exists within any object containing air like a building, the human

body and “empty” bottles

The weight of 20,000 miles of atmosphere = 14.7 lbs/sq.inch = Hg

rising 30 inches .

Measuring Air Pressure

n barometer

Changes in Atmospheric Pressure

a. Factors/Variables that cause atmospheric pressure

to change:

b.Effect of on air

pressure:

As air temperature ; (air molecules move further apart/become less dense) – the air pressure

c. Effect of air pressure:

As humidity , air pressure – because when water

vapor molecules enter the air, they replace heavier air molecules


d. Effect of on air pressure As altitude , air pressure (less air is above and air is less dense Mapping an Air Pressure Field are lines that connect points of equal air pressure. Showing air pressure distribution in this way makes patterns easier to see. On U.S. Weather Bureau maps, the interval between isobars is . Isobars can be used to identify "Highs" and "Lows". The pressure in a high is greater than the surrounding air. The pressure in a low is lower than the surrounding air.

Directions: 1. Begin drawing from the 1024 millibars station pressure over Salt Lake City, Utah (highlighted in gray). 2. Remember, isobars are smooth lines with few, if any, kinks. 3. Repeat the procedure with the next isobar value. Remember, the value between isobars is 4 millibars. 4. Label each isobar with

the appropriate value. Traditionally, only the last two digits are used for labels.

5. Label the center of the high pressure area with a large blue "H".

6. Label the center of the high pressure area with a large red "L".

On weather maps, is represented by a three digit number to the upper right of a circle; this circle represents a city on the map. 053 Rules to follow to determine the value of this number: A decimal point is omitted between the last 2 digits on the right. The number 9 or 10 is omitted in front of this number. If the original number is above 500, place a 9 in front. If it is below500, place a 10 in front. (Hint: use whichever will give a result closest to 1000 mb) Example: 053 – 1005.3


LOW

HIGH

Called:

Air is:

Caused by:

Winds blow:

Rotates:

Weather:

Barometer:


Wind The horizontal movement of air parallel to Earth’s surface. **All wind deflects to the ______________________in the Northern Hemisphere**

A. What Makes the Wind Blow?

1. Uneven heating at Earth’s surface

2. Examples:

a.

b.

c.

Sea Breeze/Land Breeze

During the day, the sun heats both land and water. Because of its lower specific heat, land heats faster and cools more rapidly than

water. The heated air above land rises, which creates an area of low pressure. The air above the sea is cooler, creating an area of

higher pressure. The cooler air in the area of high pressure above the sea moves to the area of low pressure over land. This is

called a "sea breeze" because the breeze is coming from the sea.


At night, land continues to cool more rapidly than water, which means the sea is now warmer than the shore. Now the air

above the sea becomes warmer than the air above the land. The air again moves from higher (over the land) to lower (over the sea)

pressure.

Directions: Using the diagrams of Sea Breeze or Land Breeze, answer the following questions.

1. In the diagrams, what are the circular motions of air called?

2. What causes these circular motions of air to occur?

3. Why is the warmer air rising while the colder air is sinking?

4. Why is the land significantly warmer in the daytime when compared to the ocean?

5. Why is the land significantly cooler at night when compared to the ocean?

6. During the daytime, would you face towards the land or the ocean to feel a breeze blowing on your face?

7. Would this daytime breeze be warm or cool?

8. Would you face towards the land or ocean to feel a breeze on your back at night?

9. Would this nighttime breeze be warm or cool?

10. Make a general statement concerning how large bodies of water affect the climate of nearby coastal communities.


Wind Direction and Speed

1. Winds always blow from regions of pressure to regions of

pressure.

nWind is represented by this symbol at a

:

n The direction of the line always points to the center of

the circle (in this case pointing east) and indicates the

direction in which the wind is blowing at this location.

n Each “feather” represents the wind speed –

n Whole feather =

n Half feather =

2. The speed of the wind is determined by the

.

3. Pressure gradient – difference in ÷ distance between cities. 4. As the pressure gradient increases (isobars are very close together), wind speed

.

Coriolis Effect

n The coriolis effect – Earth’s on it’s axis

causes winds to be deflected to the in the

hemisphere and to the

in the hemisphere.

n The unequal distribution of Insolation causes unequal heating of the

Earth which causes differences in pressure which result in winds.

n air, being more , sinks toward Earth due to

gravity, causing


n Earth’s rotation causes the which results in the three

(or six) cell circulation of winds as illustrated in your notes.

n Earth Science Reference Table

Air Masses

What is an Air Mass?

An is a large body of air in the troposphere moving in a particular

direction, with the same , and

throughout.

1. Source Region =

2. Types of Air Masses

a. – originates in the tropics (low latitudes). Characterized by

.

b. – originates in polar regions (high latitudes). It is characterized by

.


c. – originates in ice covered arctic regions (winter only). It is

.

d. – originates over land masses. It is .

e. – originates over water. It is .

3. Air masses are a combination of

4. Fronts –

Types of Fronts

n

n

n

n

Front Symbols

n The direction of the points or half circles indicates the direction that the

front is moving. In this case it would be moving North

Station Models

n Each circle represents a

city, the amount of fill in the

circle represents the sky

conditions


Severe Storms

Thunderstorms:

• A storm that generates and .

• Frequently produce strong winds, heavy rain, and hail.

• At any given time, there are an estimated thunderstorms in progress on

Earth.

• In the US, Florida and the eastern Gulf Coast region experience the most activity.

• Develop when air rises in an environment.

Tornadoes

Violent windstorms that take the form of a column of air called a

, which extends downward from a

cloud.

The US experiences approximately 700 tornadoes each year.

Greatest occurrence is from (but can happen anytime). Most frequently in the !

Measured using the .

Hurricanes A hurricane is a heat engine that gets its energy from .

These storms develop from tropical depressions which form off the coast of Africa in the warm

Atlantic waters. When in the form of heat.

, releasing heat

which sustains the system.

A tropical depression becomes a hurricane when its sustained recorded winds reach 74 mph. •

• Although hurricane forecasting has improved over the years tremendously, the path of these storms may only be approximated.