Welcome Scouts
Meteorology Study of the atmosphere Aristotle coined the term in 340 B.C. Thermometers and Hygrometers (1600 and 1700s) Telegraph in 1843 led to early maps Concepts of air masses and fronts in 1920s Upper air balloon observations of temperature, humidity, and pressure in 1940s
Meteorology Computer generated forecasts (1950s) Satellite Imagery (1960s) Operational Doppler Radar (1980s) Modernization of NWS (1990s) 2000s ??????????
How Weather Affects: Travel Industry Construction Industry Pilots need to know wind speed and direction for fuel concerns Construction Industry Concrete sets @ different temps and ruined by rain Forecasts can help plan efficient jobs Agriculture Industry Planting and harvesting dates Frost protection
Clouds
Safety Rules for Weather
What causes the Wind to blow? Wind is the movement of air The movement of air is caused by differences in pressure Differences in pressure are caused by the uneven heating of the earth’s surface
What is pressure?
What is pressure?
What is pressure?
Differences in Pressure
Differences in Pressure
Differences in Pressure
Air Masses
Temperature Map from Thursday
Surface Map with Cold and Warm Fronts
Temperature Map
Cross Section of a Cold Front
Cross Section of a Warm Front
Why does it rain? Moist air Some way to move the air upward Fronts, mountains, warm summer days
Cloud Simulation
How does Lightning form?
How does Lightning form?
How does Lightning form?
How does Lightning form?
How does Lightning form?
How does Lightning form?
How does Lightning Form? Moving air in a cumulonimbus separates positive and negative charges within the cloud Lightning is a result of a discharge between the differing charges
How does Lightning form?
How does Lightning form?
How does Lightning form?
How does Lightning form?
How does Lightning form?
How does Lightning form?
How does Lightning form?
How does Lightning form? Actually she is alive and well!
How does Lightning form?
How does Lightning form?
What is Acid Rain? Atmospheric water that is more acidic than normal Also includes acid in the “dry” form that interacts with the biosphere pH level below 5
pH levels across the U.S.
What is Acid Rain? Caused by burning of fossil fuels (coal, oil, natural gas) Cars and Factories source of emission Emissions: sulfur dioxide and nitrogen oxide
What is Acid Rain?
Consequence of Acid Rain Acid rain can be absorbed into the ground water, thus contaminating: water used for human consumption (cause respiratory problems in children) water used for plant consumption (lowers plant resistance to disease) water used by aquatic life (dying fish)
Water Cycle
Constructing a Barometer Record the change in pressure (up, down, or steady) on a daily basis Low pressure associated with “bad” weather such as high winds, rain, severe weather High pressure associated with “good”weather such as light winds, no rain, clear skies
Constructing a Barometer Keep barometer in a controlled climate (a room where temperature does not change) Make predictions of weather based on change in daily pressure
Constructing a Hygrometer Keep hygrometer in a well ventilated area Record the Relative Humidity on a daily basis
Constructing a Hygrometer Relative Humidity may be thought of as: amount of moisture in the air/amount of moisture that can be held in the air at a particular temperature Make predictions of weather based on moisture in atmosphere
Notes found on the web at: http://www.public.iastate.edu/~paulca/scout_pres/index.htm