1. Weather
SOL 6.3 and 6.6

2. Identify and explain the composition, properties, layers, and structure of the atmosphere.
Analyze the properties that can be observed and measured to predict air quality: air pressure, humidity, moisture, and temperature and air quality.
Examine evidence (charts and graphs) that atmospheric properties can be studied to predict atmospheric conditions and weather hazards
Analyze the role of the sun in the heating and cooling that forms clouds and order the sequence of events that takes place in the formation of a cloud
Relate the three states of water to the water cycle.
Compare and contrast types of precipitation, cloud types, and relate cloud types to weather conditions and their location in the atmosphere
Map the movement of cold and warm fronts, and interpret their effects on observable weather conditions. Interpret basic weather maps, and make forecasts based on the information presented.
Compare and contrast weather-related phenomena including thunderstorms, tornados, hurricanes, and drought.
Assess the use of technology in predicting, monitoring, and recording atmospheric phenomena. Weather satellites role
Analyze and explain some of the effects that natural events (forest fires and volcanic eruptions) and human activities may have on weather, atmosphere, and climate.
Analyze and explain the difference in average winter temperatures among areas in central and western Virginia and cities and counties along the Chesapeake Bay and Atlantic coast.

3. Earths Energy Budget
The Earth’s atmosphere is 78% nitrogen, 21% oxygen, and the rest trace gases including; argon, carbon dioxide, and water vapor

4. Earth’s Energy Budget: 51% absorbed by the surface 19% absorbed by atmosphere Remaining 30% lost back to space… COPY THE PICTURE

5. The Earth receives only a very small portion of the sun’s energy, yet this energy is responsible for powering the motion of the atmosphere, the oceans, and many processes at the Earth’s surface.
Incoming solar radiation is in close balance with the energy that leaves the atmosphere; otherwise the Earth would heat up or cool down. Excess carbon dioxide and other gases may disrupt this balance, creating a Greenhouse Effect.
About 1/3 of the sun’s incoming energy is reflected back out to space. About 1/2 of the energy striking the Earth is absorbed by the surface.
The Earth’s surface is heated unequally. This is due to the tilt of Earth on its axis. The equator gets more sun the poles get less.
Radiation and convection from the surface transfer heat energy. This energy powers the global circulation of the atmosphere and the oceans on our planet. Remember that heat rises, cools and sinks.
The sun is responsible for most energy sources on Earth

6. How does the amount of energy Earth receives from the sun compare with the energy the leaves Earth?
What do you predict would happen if there was a shortage of incoming solar radiation?
What would happen if Earth retained more thermal energy?

7. Energy Transfers
Radiation brings all of the energy to the Earth from the sun
Convection currents redistribute the energy throughout the atmosphere and the oceans.

8. Currents in the Atmosphere and Oceans
Convection currents redistribute the energy all over the planet that comes from the sun. The average mean temperature is fairly warm because of these currents.

9. Air Pressure
Air pressure is the amount of air pushing down on us. It is measured with a barometer
Low pressure means lousy weather, cool & rainy
High pressure means fair weather, warm & sunny
Increase in altitude = decrease in air pressure

10. Humidity Humidity is the amount of water vapor in the air
The more humid the air is the more uncomfortable you feel
100% humidity is fog (stratus cloud formed on the ground)
It is measured with a psychrometer or hygrometer
Dew point is the temperature at which the air becomes 100% humid

11. Atmospheric Layers Layers are defined by changes of temperature
Troposphere: weather takes place & clouds are found
Stratosphere: jet stream and the ozone layer is found
Mesosphere: coldest and stops most meteorites (burn up)
Thermosphere: top most layer, it is divided into the ionosphere (northern lights) and the exosphere (satellites)

14. Why Protect the Air? Watch & Summarize in your notes

15. Winds are named from the direction in which they travel from
Easterlies
Horse Latitudes
Doldrums
The Westerlies dominate the weather in the United States.
Trade winds are warm, steady breezes that blow continuously.
Wweak surface winds the equator, this area is called the doldrums.

16. Cloud Formation

17. Types of Clouds Fair Weather Clouds Fair now, bad weather
in the next 24 hours
CIRRUS
Thunderstorm Clouds
Days of rain
Nimbostratus
Overcast drizzle

18. What is weather?
Weather is caused by the unequal heating of the Earth’s surface. Warm air rises and cool air sinks
Warm air = high pressure
Cold air = low pressure

19. How to read a weather map

20. Thunderstorms
Thunderstorms – cold meets warm front forming heavy rainstorms with thunder and lightning.
When the air is heated by lightning it expands quickly resulting in loud sound waves (thunder).
Lightning – sudden discharge of electricity between cloud and cloud; cloud and ground. Leading cause of forest fires. Can strike people, animals, or building.
Safety – avoid open spaces outside; don’t go under trees for shelter, avoid sinks, bathtubs, televisions, and telephones while inside during a lightning storm.

21. Hurricane, Cyclone, Typhoon
Hurricanes – power cyclones that form over tropical areas.
Typhoon – hurricane that forms over the Pacific ocean.
The eye of the storm is calm but the winds reach speeds of 74 to over 155 m/hr.
High winds, storm surges, flooding, LOW PRESSURE
Most powerful of all storms.

22. Tornadoes Very destructive & most violent
Rotating counter-clock wise, funnel-shaped
Develops in low, heavy cumulonimbus clouds.
Acts like a giant vacuum cleaner
LOW PRESSURE!!!
Associated with severe thunderstorms
Occur in tornado alley in the United States only

23. Weather Symbols
High Pressure System: Sunny weather will often occur under high pressure
Low Pressure System: lousy weather, spins counter clockwise
Cold Front:. When the cold front passes the temperature drops and the rising air along the front can bring precipitation
Warm Front can bring precipitation especially in the region where the warm front is approaching.

24. A stationary front has a little or no movement, rain for days
Occluded Front: cold front that overtakes a warm front.
They commonly occur close to a maturing low pressure system

25. Weather Maps

26. Isobars-connect areas of equal pressure

27. Weather Instruments: Copy when I pause

28. Make sure you know:
Warm, moist air is less dense than cold, dry air, so it rises relative to colder, drier air.
Warm, moist air rises and actually gives off some heat as the moisture condenses
Air exerts pressure. Air pressure decreases with altitude.
Forest fires and volcanic eruptions are two natural processes that affect the Earth’s atmosphere. Many gaseous compounds & particles are released into the atmosphere by human activity.
The amount of heat energy, water vapor, and the pressure of the air largely determine what the weather conditions are.
Air pressure is measured in millibars
The Coriolis Effect makes winds rotate to the right (clockwise) in the Northern Hemisphere