Chapter 1 Atm/weather

Front 1

Define weather

Back 1

The state of the atmosphere at some place and time, described in terms of such quantitive variables as temperature, humidity, cloudiness, precipitation, wind speed, and wind direction.

Front 2

Define meteorology

Back 2

The study of the atmosphere and the processes that cause weather.

Front 3

Define climate

Back 3

Weather conditions at some locality averaged over a specified time period.

Front 4

Define climatology

Back 4

The study of climate, its controls, and spatial and temporal variability.

Front 5

What is N.W.R?

Back 5

NOAA Weather Radio, a valuable source of local weather information.

Front 6

What is N.O.A.A?

Back 6

National Oceanic and Atmospheric Administration; a federal agency that conducts research and gathers data about the global oceans, atmosphere, space, and sun and applies this knowledge to science and service that touch the lives of all Americans.

Front 7

What is N.W.S?

Back 7

National Weather Service; operates low-power, VHF high band FM radio transmitters that broadcast continuous weather information directly from NWS forecast offices 24 hrs a day.

Front 8

What is S.A.M.E?

Back 8

Specific Area Message Encoding; feature sounds an alarm only if a weather watch or warning is issued specifically for a county or limited local area programmed by the user.

Front 9

Pressure System

Back 9

A region of the Earth's atmosphere where air pressure is unusually high or low.

Front 10

High Pressure System (weather, winds)

Back 10

Accompanied by fair weather and hence are described as fair-weather systems. The ones that originate in northwestern Canada bring cold, dry weather in winter and cool, dry weather in summer to much of the coterminous United States. Highs that develop further south over land may bring hot, dry weather in summer and mild, dry weather in winter. Surface winds blow in a clockwise and outward spiral. Calm conditions or light winds over broad area at the center.

Front 11

Low Pressure System (weather, winds)

Back 11

Produce cloudy, rainy or snowy weather and often described as stormy-weather systems. Surface winds blow in a counterclockwise and inward spiral.

Front 12

Air Pressure

Back 12

The weight per unit area of a column of air that stretched upward from the Earth's surface to the top of the atmosphere.

Front 13

Air Mass

Back 13

Huge volume of air covering hundreds of thousands of square kilometers that is horizontally relatively uniform in temperature and humidity.

Front 14

Cold air mass

Back 14

Form at ghieger latitude over surfaces that are often snow or ice covered.

Front 15

Warm air mass

Back 15

Form in the lower latitudes where the Earth's surface is relatively warm.

Front 16

Humid air mass

Back 16

Form over moist maritime surfaces.

Front 17

Dry air mass

Back 17

Develop over dry continental surfaces.

Front 18

Four basic types of air masses

Back 18

cold and dry, cold and humid, warm and dry, warm and humid

Front 19

Front

Back 19

Narrow transition zone between air masses that differ in temperature, humidity, or both. Form where contrasting air masses meet, and the associated air movements often give rise to cloudiness and precipitation.

Front 20

Stationary front

Back 20

stationary

Front 21

Warm front

Back 21

The cold air forms a wedge under the warm air and the leading edge of warm air at the Earth's surface.

Front 22

Cold front

Back 22

Cold air advances by sliding under and pushing up the less dense warm air and the leading edge of cold air at the Earth's surface.

Front 23

Maximum temperature

Back 23

the lowest air temperature recorded over a 24-hr period, usually between midnight of one day and midnight of the next day.

Front 24

Minimum temperature

Back 24

lowest air temperature recorded over a 24-hr period

Front 25

Dew point (frost point)

Back 25

temperature to which air must be cooled at constant pressure to become saturated with water vapor and for dew (or frost) to begin forming on relatively cold surfaces.

Front 26

Relative humidity

Back 26

actual concentration of the water vapor component of air compared to the concentration the air would have if saturated with water vapor. Expressed as a percentage.

Front 27

Precipitation amount

Back 27

Depth of rainfall or melted snowfall over a 24-hr period

Front 28

Wind direction

Back 28

compass direction from which the wind blows

Front 29

Wind speed

Back 29

tends to increase as a cold front passes a location and winds are particularly strong and gusty in the vicinity of thunderstorms

Front 30

sky cover

Back 30

based on fraction of sky that is cloud covered
clear (no clouds)
few clouds (1/8 to 2/8)
scattered clouds (3/8 to 4/8)
broken clouds (5/8 to 7/8)
overcast (completly cloud covered)

Front 31

weather watch

Back 31

issued by National Weather Service when hazardous weather is considered possible on current or anticipated atmospheric conditions

Front 32

weather warning

Back 32

issued by the National Weather Service when hazardous weather is imminent or actually taking place

Front 33

What is G.O.E.S?

Back 33

Geostationary Operational Environmental Satellite

Front 34

Subsatellite point

Back 34

the location on Earth's surface directly below the satellite , essentially on the equator.