Weather and Climate Notes

Measuring our Weather

temperature: measures the average kinetic energy of the particles in an object can be measured with a thermometer in both

Fahrenheit and Celsius scales when measuring something cold the red alcohol

contracts (moving down) when measuring something hot the red alcohol expands

(moving up)

refer to figure 13 on text pg.546

Measuring our Weather

heat: a transfer from a higher temperature substance to lower temperature substance

PRACTICE

1. What is the temperature in degrees Celcius?

2. What is the temperature in degrees Farenheit?

Formula for Celsius:

Formula for Fahrenheit:

°C = (°F – 32) X 5 / 9

Let’s Practice:Convert 98 ° F Convert 89 ° F Convert 75 ° F

°F = °C x 9 / 5 + 32

Let’s Practice:Convert 26 ° C Convert 0 ° C Convert 14 ° C

Converting Temperatures

Humidity

Humidity the amount of moisture in the air

Relative humidity becomes the percentage of the humidity in the air around us

Dewpoint is when the air become 100% saturated with water

Instruments to measure Humidity

Hygrometer

Consists of a scale with a strand of fiber connected to a pointer.

This allows you to read the relative humidity inside

Sling Psychrometer

Contains 2 thermometers: a wet bulb and a dry bulb

You use both bulb temperatures to figure out the relative humidity

Instruments used to collect information

Barometer: Air pressureThermometer: temperatureAnemometer: measure wind speedWind vane: measure wind direction

(all winds must be in the same direction for a hurricane to form)

Hygrometer: relative humidityPshychrometer: relative humidity

Reading Isobars for Measuring Air Pressure

On a weather map, a line connecting points of equal air pressure is called an isobar.

Remember, isobars go in increments of 4.

AIR MASS

A large body of air throughout which temperature and moisture are similar.

EX:Continental air mass: form over large landmassesMaritime air mass: form over oceansTropical air mass: form over deserts of the southwestern U.S. Polar Air Masses: form over ice and snow covered land.

FRONTS

Fronts occur where air masses of different temperatures meet, and a boundary between them is formed.

There are three specific types of fronts that affect us: cold front, warm front, and a stationary front

Cold Front

Along a cold front, the air doesn’t mix, this happens because hot air rises and cold air sinks.

WARM FRONT

If air is advancing into a region of colder air, the warmer front is formed.

The warm less dense air slides up and over the colder, denser air mass.

STATIONARY FRONT

A stationary front, is a front where a warm air mass and a cold air mass meet but neither advances.

Wind Patterns

Wind and Ocean Currents

Global wind belts, such as the trade winds and Westerlies are a major factor affecting the flow of ocean surface water.

The Westerlies push ocean currents eastward in the higher latitudes of the northern and southern hemispheres.

Air Pressure

Air pressure is an air flow, or wind around a system that always spirals around the center of that area.

High air pressure is usually clockwise flow of air in the NHand counter clockwise in the SH.

Low air pressure is always compensating for the loss of mass and goes counter clockwise in the NH and clockwise in the SH

Tornadoes• A dark funnel cloud of strong winds that

spiral upward.

• Air pressure inside the tornadoes funnel is much lower than the air pressure outside which make it act like a huge vacuum cleaner.

• The region in the U.S. where most tornadoes occur is called Tornado Alley (central U.S.)

Parts of a tornado

Becomes tornado once it reaches the ground

vortex

Funnel cloud

JET STREAMS Jet streams cause a strong “river” of strong

winds high above the surface of the earth. Jet Streams are a narrow band of strong winds in the upper atmosphere.

Jet Streams are stronger in the winter, since the temperature difference at the front boundaries are greater during this time.

LOCAL WINDS Sea breeze: Cooler air that moves in

toward the land again to replace the warm air that is rising. This air then moves inland from the water

Land breeze: Since land cools quicker than water, air over the warmer water rises and flows toward the cooler land where the air sinks.

CAN YOU LABEL THIS MAP?

97 % of Earth’s water is salt water found in the oceans and seas. This leaves us with 3% of Earth water that is fresh

water that we can use. 1% is in the and the other 2 % of Earth water is frozen in

lakes and rivers

glaciers.

Since water makes-up the ¾ of the Earth’s surface it is very important to learn more about it. To learn more we must learn about the water cycle.

Earth’s water is always in one of the three states

of matter. When water’s temperature is at or

below 0 degrees Celsius it becomes a solid, called ice. When the water’s temperature

is 100 degrees Celsius or above it becomes a gas, called water vapor.

When the water’s temperature is in between 0 degrees Celsius and 100 degrees Celsius it is a liquid.

The Hydrologic Cycle

“WATER CYCLE”

Precipitation

Precipitation is any form of water that falls from the sky, such as rain, hail, snow, or sleet.

What is evaporation?

Evaporation is the process of changing liquid water into water vapors. The Sun’s energy creates the change by heating-up the water particles. The higher the temperature, the faster the water changes from a liquid to a gas.

Where does the water come from? The water is stored in lakes, ponds, puddles, oceans, glaciers, marshes, soil and spaces in rocks.

Transpiration

Some water also comes from green plants, especially their leaves, this process is called transpiration. Transpiration helps cool the plants down, just like when we sweat our body is cooling us down.

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What is condensation?

Condensation is the process in which water vapor becomes liquid water. During the evaporation process the water vapors begin to cool as they rise, therefore the particles are slowing down. What makes a cloud? A cloud is made of tiny drops of water or ice crystals. The droplets combine to form clouds. The drops of water collect until they so heavy that gravity pulls them down as rain also know as precipitation.

Percolation

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Percolation is the movement of water through the soil. The prime moving force of groundwater is gravity.

Where does the water go?• Infiltration happens when precipitation is absorbed into the

ground• Runoff happens when too much precipitation falls too quickly and

it “runs” over the ground• In both cases the sun can warm it and it can evaporate to take

part of the Water Cycle (Hydrologic Cycle)

Watch MovieWATER CYCLE