Bellringer – Match the layer of the atmosphere with its description Exosphere Mesosphere Stratosphere Thermosphere Troposphere Contains the ozone layer Closest layer to Earth’s surface Coldest temperatures Extends into outer space Very hot layer

Atmospheric Moisture

Humidity Humidity – the amount of water vapor in the air Maximum Saturation – the most water vapor the air can hold

Humidity Warm air can hold more water vapor than cold air, which is why the summer tends to be more humid than the winter

Humidity Relative Humidity – how much water vapor is in the air compared to how much water vapor the air is able to hold Relative humidity = current humidity/maximum saturation 100% relative humidity means that the air is holding its maximum amount of water vapor (the air is at maximum saturation)

Humidity Dew Point – the temperature when air becomes cool enough for water vapor to condense into liquid water Condensation – gas  liquid (water vapor  liquid water)

Humidity The higher the dew point, the higher the relative humidity for that day

Humidity Summary: As temperature increases, so does maximum saturation Maximum saturation = 100% relative humidity The higher the dew point, the higher the relative humidity

Review: Air contains water vapor Air is warmed by Earth’s surface and rises. Air that is far away from Earth’s surface cools down and sinks. This creates a convection current

Cloud Formation When the warm air rises, water vapor in the air cools down When the air reaches its dew point, the water vapor condenses into tiny water droplets

Cloud Formation These droplets form around condensation nuclei, small dust particles in the air where cloud droplets can form Millions of these tiny droplets join together to form clouds

Cloud Formation Clouds – condensed water vapor (aka, tiny liquid water droplets) suspended in the atmosphere

Cloud Formation For a cloud to form, you must have 3 things: Water vapor in the air Dust particles for the droplets to form around (condensation nuclei) A change of temperature or pressure (to create convection currents)

Types of Clouds Clouds are characterized by their size, shape, and altitude (height)

Types of Clouds Cirrus – thin, feathery clouds that form at high altitudes Fair weather, but can be seen before rain or snow

Types of Clouds Cumulus – white, puffy clouds usually on fair-weather days

Types of Clouds Stratus – low-lying layered sheets of clouds “Cloudy” days (clouds all day, but usually little or no rain)

Types of Clouds Nimbus – low-altitude, gray rain clouds

Types of Clouds Other clouds are combinations of the main types of clouds

Types of Clouds Cumulonimbus – storm clouds

Types of Clouds Stratocumulus Nimbostratus

Other Cloud Types Cirrocumulus Cirrostratus

Types of Clouds Fog – clouds that form near the Earth’s surface

Types of Clouds

Rare Clouds https://m.youtube.com/watch?v=wiFyg0i9K3M

Precipitation Coalescence – Cloud droplets colliding and joining together, making larger and larger droplets Eventually, they become too heavy and fall to the ground as precipitation

Precipitation Precipitation -- any moisture that falls from the atmosphere Four main types of precipitation: Rain Snow Sleet Hail

Precipitation Sleet -- pellets of ice formed when raindrops fall through freezing air

Precipitation Hail – lumps made of layers of ice from cumulonimbus clouds

Precipitation Hail forms from droplets in the cloud constantly melting and refreezing

The Clumsy Meteorologist You are working with your tablemate You will need coloring pencils, a glue stick, and 2 pairs of scissors Draw the descriptions FIRST, then match the steps with the descriptions and put them in order Raise your hand when you are ready to glue down your steps. I must approve it first. CLEAN UP AND RECYCLE ALL PAPER! Return pencils, glue, and scissors back to the right place. Turn in when done and complete vocab assignment

The Clumsy Meteorologist If you finish, on a separate sheet of paper, write a paragraph describing how a cloud forms. DO NOT JUST RESTATE THE STEPS FROM THE ACTIVITY. Discuss with your partner, and put it in your own words.