Do Now What causes weather? What is the difference between weather and climate?

Climate vs. Weather Weather The current state of the atmosphere. What is going on right now. Caused by UNEVEN HEATING of the Earth’s surface Climate Average temperature and precipitation over many years.

Temperature Pressure Wind Humidity Weather Factors Temperature Pressure Wind Humidity

= = Temperature Heat moves from where it’s HOT to COLD Measure of the average kinetic energy of molecules in a substance = More Kinetic Energy Faster Molecular Movement Less Kinetic Energy Slower Molecular Movement = Heat moves from where it’s HOT to COLD

The Earth (Re-radiates Sun’s Energy) Temperature What is the primary source of heat energy in the atmosphere? The Sun The Earth (Re-radiates Sun’s Energy) Factors that affect temperature Time of day Time of year Latitude Elevation

Time of year and Temperature Angle (Height in the sky) of the Sun = ANGLE OF INSOLATION SUMMER: MORE HEAT Sun is out longer and is higher in the sky Summer Winter More direct angle Less direct angle WINTER: LESS HEAT Sun is not out as long and is lower in the sky

Latitude and Temperature The further from the Equator you get the cooler the temperatures The sun’s energy is less direct. Equator

Isotherms Lines on a map that connect points of equal temperature

Do now Describe how the height of the sun in the sky affects the temperature of an area

Do now Describe what factors affect the temperature of an area and what the effect is. (ex. Elevation- higher elevations means colder temperatures.) List the tool used to measure the following (look in your packet if you can’t remember) Pressure Temperature Wind Speed Wind Direction

Pressure- Measured with a barometer Pressure is the weight of air pushing down. Warm Air Rises (Low Pressure) Cool Air Sinks (High Pressure) Describes the air systems that cause weather. HIGH PRESSURES: Cooler Less Moisture H Good Weather LOW PRESSURES: Warmer More Moisture Bad Weather L

Isobars Lines on a map that connect points of equal pressure

Winds – Horizontal air movements Winds are caused by differences in air pressure. Wind blows from HIGH pressure to LOW Pressure Winds named for the direction from which they come. Ex. Wind from the south west = Southwesterly wind. Ex. A breeze blowing onshore from the sea = sea breeze. Wind vane – measures direction Anemometer – measures wind speed

Land vs. Sea Breeze Sea Breeze = Cooler, denser, high pressure air over water blows towards land, Low Pressure (Daytime). Land Breeze - Cooler, denser, high pressure air over land blows towards sea, Low pressure (Night time).

Humidity Humidity is the amount of moisture in the air. (%) High humidity  a lot of moisture Will feel sticky outside Precipitation most likely Low humidity  less moisture Will feel dry and comfortable Precipitation not likely Humid locations are near large bodies of water

Do now Describe how a sea breeze and a land breeze form.

Air Masses Air masses are large bodies of air which have similar temperature and moisture characteristics. Air masses form when air stays over a region (called the source region) for several days. Air masses that form over water will be moist. Air masses that form over land will be dry.

A = Arctic P = Polar T = tropic c - continental = dry m - marine = moist A = Arctic P = Polar T = tropic

Do Now Describe the properties of a cP air mass and a mT air mass Explain what happens when wamr air and cold air meet

Fronts – boundary that separates 2 air masses with different temperatures Air becomes unstable at fronts. Produces: Clouds Strong winds Precipitation Other weather changes

Cold Front Cold air pushes out warm air, *snow Plow* Move faster than warm fronts Short-lived thunderstorms Precipitation occurs at the frontal boundary.

Warm Front Warm air rises over cold air. Longer and steady precipitation Precipitation occurs far ahead of the front.