Chapter 5, lesson 1 Standards : Sc. 6. E. 7.2, SC.6. E. 7.6, SC.6.E. 7.7 Learning goal : TSWBAT understand weather, the variables that affect weather and how weather is related to the water cycle.

1. Weather is the short term changes in the atmosphere in a certain place at a specific time. 2. Weather changes quickly videos/weather-101-sci videos/weather-101-sci 1. Variables are used to describe the weather. 2. Temperature and rainfall are more common variables. 3. Meteorologists ( scientists who study and predict weather) use many variables to describe a variety of atmospheric changes. a. Air temperature, air pressure, wind speed, wind direction, humidity, cloud coverage, and precipitation. Remember: a VARIABLE is something that CHANGES

AIR TEMPERATUREAIR PRESSURE  Measures the kinetic energy of molecules in the air.  Molecules in warm air move faster than molecules in cold air.  Air pressure is the pressure that a column of air exerts on the air or a surface below.  Air pressure decreases as altitude increases.  Colder air has higher air pressure than warm air.  Air pressure is measured with a barometer.

WIND SPEED HUMIDITY  Remember: wind is the movement of air from an area of high pressure to an area of low pressure.  The tool used to measure wind speed is called an anemometer.  Humidity is the amount of water vapor in the air. anemometer

RELATIVE HUMIDITY DEW POINT  This is the amount of water vapor present in the air compared to how much the air can hold.  This is shown as a percentage (%)  Warm air can hold more water vapor than cold air.  This is the temperature where air is FULLY saturated (full of moisture) because of decreasing temperature.  Think of a sponge. When it is full of water, it drips water. When air becomes saturated with water vapor, the water vapor condenses and forms water droplets. Relative humidity is measured with a psychomotor

 Clouds are water droplets or ice crystals suspended in the atmosphere.  A cloud that forms near Earth’s surface is called fog.

 This is water, in liquid or solid form, that falls from the atmosphere.  inter% /P-Type_files/image005.gif inter% /P-Type_files/image005.gif

SnowSleetFreezing rainrain

Define these words, using your books or interactive notebooks  weather  air pressure  precipitation  humidity  relative humidity  dew point  water cycle