Weather

Weather is.... Weather: The state of the atmosphere at a specific time and place

Temperature Thermometer is used to measure temperature. TEMPERATURE=the average motion of molecules ↑ TEMP= ↑movement of molecules= feels hot ↓ TEMP= ↓movement of molecules= feels cold

Warm air= expanding or rising air= leaves behind L pressure Cold Air=sinking air= leaves an area of H pressure Air Pressure

What causes winds? A wind is a horizontal movement of air from a area of high pressure to an area of low pressure It is this difference in pressure that makes the air move (wind) Winds are measured by direction and speed The anemometer is the tool we use to measure this Wind chill=↑ cooling the wind causes

Local Winds: The land cools and heats faster than the ocean Local Winds: The land cools and heats faster than the ocean. Water holds heat longer than land, and takes longer to heat or cool. During the day, the land gets hotter faster than the water. The heated air rises, leaving behind an area of low pressure. Wind from the cooler sea blows in to take the place of that warmer air. SEA BREEZE:

Land Breeze: At night the lands cools off faster than the sea Land Breeze: At night the lands cools off faster than the sea. Cool air sinks creating an area of high pressure. Wind blows from the land to the sea.

Intense heat = Powerful CONVECTION Warm, moist air rises and leaves behind an area of low pressure. This is why most rain forests are found along equatorial regions. That air rises until it reaches the top of the troposphere, where it can’t rise any further. It spreads out towards the polar regions: HOT follows COLD wanting to share its warmth. As it spreads it begins to cool and sink, sinking air produces an area of H pressure with dry conditions= desert regions on earth

Humidity Humidity: measure of the amount of water vapor stuck between molecules in the air. Temperature* The hotter the air, the more water the air can hold Cold air: molecules move slower so droplets of water can start to stick together=condensation 100% = air is saturated (rain) Temperature at which air becomes saturated is the dew point. A hygrometer is used to measure humidity.

Air Masses Air masses are masses of air that have the same characteristics of the surface over which it develops Pressure Systems descending (going down)=H pressure ascending (going up)=L pressure

This is the symbol for a warm front warm air slides over departing cold air and large bands of precipitation form

This is the symbol for a cold front Cold Fronts Cold air pushes under a warm air mass. Warm air rises quickly and narrow bands of violent storms form

This is the symbol for an occluded front 2 cold air masses merge and force warm air between them to rise quickly. Strong winds and heavy precipitation will occur

This is the weather map symbol for a stationary front Warm or cold front stops moving. Light wind and precipitation may occur across the front boundary

Reading a weather map Isotherm: Connects areas of equal temperature; therm means temperature

Reading a weather map ISOBAR= connects areas of equal pressure. BAR comes from BARometric pressure