Meteorology is the physical and
chemical science of the atmosphere. Meteorologists study and predict the
weather. The interaction of the oceans and atmosphere, including solar
radiation helps us understand how weather forms and sustains itself.
Describing the weather and how it changes
is recorded on weather maps or synoptic chart. Information on temperature,
pressure, wind, radiation, and condensation helps meteorologists to predict
future weather patterns. The weather can be divided into its meteorological
elements, which describe the physical condition of the atmosphere, land, and
Temperature. The air temperature is
measured by a thermometer over which air is allowed to freely flow over the
bulb, but protected from solar and terrestrial radiation.
Atmospheric Pressure. The pressure
is the weight of the vertical column upon an area. A barometer measures
Humidity. This term is used to
express the amount of water vapor in the air. Humidity is usually measured by
the change in length of hygrometric substances giving relative humidity.
Wind Velocity. This describes the
speed and direction of the motion of the air. A knot is a measure of speed
used at sea by sailors. It is equal to one nautical mile per hour. A nautical
mile is approximately 2 kilometers.
Condensation. Water vapor may
condense into liquid or solid particles. Liquid is precipitation (rain) and
solid gives cloud cover.
Radiation. Solar radiation refers to
the number of hours of bright sunshine per day. Both solar and terrestrial are
measurable by total radiation receivers.
Visibility. This is defined as the
maximum distance an object can be distinguished against the background sky.
Observations of current temperatures,
humidity, wind, pressure, and highest and lowest temperatures are usually
transmitted by commercial radio and television systems, telephones, recording
systems, and NOAA (National Oceanographic and Atmospheric Agency) Weather
Radios for the localities they serve.
Data such as the previous day's highest and
lowest temperatures and precipitation amounts are generally carried in
newspapers for both the local areas and other cities. Many papers carry
foreign reports. Television and radio weather programs sometimes carry
selected data, primarily for U.S. cities.
Records of past weather, which also are
compiled and analyzed to describe the climate on a local, regional, or
worldwide basis, are maintained by NOAA's Environmental Data and Information
Service. The Weekly Series of Daily Weather is another source of past weather
data. It contains daily charts of surface weather patterns, upper wind
patterns, high and low temperatures, and 24-hour precipitation across the
United States for each week.
Weather is important to everyone. In many instances it
controls what we can or cannot do on a particular day. It is therefore
important to be able to read and interpret weather maps. This introduces
students to the different weather map symbols.
- Go over the "Symbols Used in
Plotting Report," especially the sky coverage. Students will have to
interpret the cloud cover of both maps from the satellite and then transfer
the information onto a blank map. Make sure that students understand the
Precipitation refers to the way
water is precipitating. Fog is low clouds. Snow is crystallized water. Rain is
liquid water. Thunderstorms can refer to severe rain, including hail. Drizzle
refers to light rain, while showers are a steady downpour of rain.
Wind speed and direction shows the
direction of where the wind in coming from. The direction can be determined by
comparing the line to north. So if the direction is south to north, you would
refer to the wind as coming from the south. The speed of the wind is measured
in knots which is a nautical term that is measured as 1.852 km per hour.
Sky coverage refers to the amount of
clouds in the sky. This may be suggestive if you are looking a satellite photo
or you are on the ground looking up.
Types of clouds refers to the clouds
present at different elevations and the form they are taking.
Fronts and pressure systems refer to
centers of high or low pressure system. The different fronts include a cold
front, warm front, stationary front, and occluded front. A cold front
is when the leading edge of air is colder air replacing warmer air. A warm
front is when the leading air mass is warm air that is replacing cooler
air. A stationary front is when the front is stalled or not moving. An occluded
front is when a cold front catches up to a warm front.
- Use the worksheet for students to draw
the symbols and to describe what each symbol means.
- Use a local weather map to see if students can
interpret the symbols found on them. Remember that sometimes the symbols
may be a little different.