Air is made up of 78% Nitrogen (N2), 21% Oxygen (O2), and 1% Misc. (Water vapor, Hydrogen, other gases)

Weather is the condition of the air around us:

• Temperature
• Precipitation - Chance, Type (Rain, Snow, Hail)
• Wind & Wind speed - Velocity (Speed, Direction)
• Sun Type (Ex. Cloudy, Sunny)
• Air pressure (Barometric Pressure)
• Humidity (Measured in %)
• Relative Humidity
• Air Quality (Quantity of impurities, measured in parts per million)
• Dew Point
• Air Front (Based on the wind, air pressure, and humidity)

Climate is weather over time.

Air pressure is the weight of the air on an object.

Hygrometer - the tool used to measure the amount of water vapor in the air

Greenhouse Gases trap the heat from the sun. While we need some greenhouse gases, too much causes global warming.

Air mass is a huge area of the atmosphere with the same air pressure, temperature, and humidity. When multiple air masses meet, precipitation occurs. This is a front.

Factors affecting precipitation:

• Temperature
• Humidity
• Latitude
• Topography - Landforms
• Altitude
• Wind

Forms of precipitation:

• Rain
• Snow
• Sleet
• Hail

Wind (Measured in speed and direction, measured by anemometer):

• Calm (>1mi/h)
• Light Air (1mi/h - 3mi/h)
• Light Breeze (4mi/h - 7mi/h)
• Gentle Breeze (8mi/h - 12mi/h)
• Strong Breeze (25mi/h - 30mi/h)
• High Wind (31mi/h - 38mi/h)
• Gale (39mi/h - 54mi/h)
• Storm (55mi/h - 63mi/h)
• Violent Storm (64mi/h - 73mi/h)
• Hurricane (<74mi/h)

Air Mass Types:

• Tropical - warm, forms over tropics
• Polar - cold, forms over poles
• Maritime - humid
• Continental - dry, forms over land
• Continental Tropical - warm, dry
• Maritime Tropical - warm, humid
• Polar Continental - cold, dry
• Maritime Polar - cold, humid

Air Front - the boundary of an air mass

• Cold Front
• Warm front
• Occluded Front
• Stationary Front

1 knot = 1.15078 mi/h

Tools

• Rain Gauge - Rain
• Barometer - Air pressure
• Anemometer - Wind Speed
• Hygrometer - Humidity
• Psychrometer - Relative Humidity