Earth and Environmental Science Atmosphere Test
The stratosphere is important because it contains nitrogen, which blocks harmful ultraviolet radiation from the Sun.
false
Infrared images
- allows meteorologists to determine the temperature of a cloud, from which they can infer its type and height - useful in detecting strong thunderstorms that extend to great heights in the atmosphere
Earth is continuously sending energy back into space
- over 1 year earth sends back just as much energy as it receives -If too much is sent it could cool off - if too little is sent it could warm up dangerously
Weather radar system
- programed to bounce off large rain drops - rotates in a circle, allowing meteorology to gauge where rain is falling within the radar's range
ITCZ
-characterized by a band of cloudiness and occasional showers that provide moisture for the tropical rain forests - also called the doldrums
5 Major types of air masses
1.) Continental tropical (cT) - warm and dry 2.) Maritime Tropical (mT) - warm and humid 3.) continental polar (cP) - cold and dry 4.) Maritime polar (mP) 5.) Arctic (A) - much colder than continental polar
4 main fronts
1.) cold front 2.) warm front 3.) stationary front 4.) occluded front
Cloud formation (3 ways)
1.) the dew point is reached, water vapor condenses around condensation nuclei. When millions of droplets collect a cloud forms. 2.) Orographic lifting 3.) When 2 air masses of different temperatures collide. -warm air moves into an area of cool air and the bulk of it is forced to rise over the more dense cool air. -As the warm air rises and cools, the water vapor condenses and forms a cloud
Ozone
A form of oxygen that has three oxygen atoms in each molecule instead of the usual two. - it is important in the upper atmosphere because it absorbs ultraviolet radiation from the sun - without it our skin couldn't tolerate exposure to the sun
Surface Observing Network
A network of weather stations that gathers data across the country in a consistent manner at regular intervals
anemometer
An instrument used to measure wind speed
Temperature inversion
an increase in temperature with height in an atmospheric layer - can include the taped cooling of land on a cold, clear winter night when the wind is calm - can worsen air pollution problems by acting like a lid to trap pollution under the inversion layer
How does convection affect the atmosphere?
Energy is transferred from the particles of air near the earth's surface to the particles of air in the lowest layer of the atmosphere - conduction only affects a thin atmospheric layer near Earth's surface
99% of the Earth's atmosphere is composed of
Nitrogen and Oxygen
Earth's atmosphere contains more _______ than any other substances.
Nitrogen and oxygen
Prevaling Westerlies
Occurs between 30-60 degrees north and south latitude in a circulation pattern opposite of the trade winds -surface winds move toward the poles in an easterly direction - determines our weather - moves away from equator in an easterly direction
Polar easterlies
Occurs between 60-90 degrees latitude -flows from northeast to the southwest in the northern hemisphere
Air particles deflect to the...
RIGHT in the NORTHERN hemisphere and the LEFT in the SOUTHERN hemisphere
Humidity
The amount of water vapor in the air
Troposhere
The lowest layer of the atmoshere, in which temerature decreases at a constant rate as altitude increases. - most weather takes place here - characterized by a decrease in temp from top to bottom - contains most of the mass of the atmosphere
Stratosphere
The second-lowest layer of Earth's atmosphere. - made up mainly of concentrated ozone - increases in temperature to the top of the layer (gets warmer)
Wind
can be thought of as air moving from an area of high pressure to and area of low pressure
orographic lifting
When wind encounters a mountain and the air has no place to go but up.
Radiosonde
a balloon-borne package of sensors that gathers upper-level weather data -these sensors measure temperature, air pressure, and humidity -sent by a radio signal to a ground station that tracks the movements of the radiosonde
Temperature
a measurement of how rapidly or slowly molecules move around - more molecules in a given space = higher temp
Energy radiated by Earth's surface is...
absorbed by the atmosphere and warms the air through conduction and convection
2 most important factors
accuracy and density of the data -refers to amount of data available
in a surface LOW-pressure system...
air rises. - the air is replaced by air outside of the system, so the are flow is inward and upward - in the northern hemisphere, the system moves COUNTER CLOCKWISE -rain and clouds
in a surface HIGH-pressure system...
air sinks and spreads away from the center - the air is deflected to the right by the Coriolis effect -makes the overall circulation move in a CLOCKWISE direction in the northern hemisphere - fair weather
source region
area over which an air mass forms
In the lower atmosphere air generally moves from...
areas of high density to areas of low density
meteorologists must gather atmospheric data...
at heights up to 30,000 m
The continual motion of air and water relocates heat energy among Earths surface, oceans, and atmosphere...
bringing it into balance
Weather we experience is largely a result of
changes that take place high in the troposphere
The amount of atmospheric water vapor on earth is always...
changing - can range from 4% to 0%
Hydrometers
cloud droplets and forms of precipitation that contains water in any phase
Condensation nuclei are particles of atmospheric dust around which ______.
cloud dropplets form
Cloud droplets collide to form larger droplets in a process called ______.
coalescence
cold front
cold air displaces warm air and forces it to rise, often creates thunderstorms
When the temperature in the atmosphere reaches the _____, condensation occurs.
dew point
Since the motion of moving raindrops is caused by wind...
doppler radar provides a good estimation of the wind speeds associated with precipitation areas, especially those experiencing thunderstorms and tornados.
When water is changed from one state to another...
heat is absorbed or released - this affects atmospheric motions that create weather and climate
As water vapor in the air condenses...
heat is released - this heat warms the air - the latent heat can provide energy to a weathering system thereby increasing its intensity
Air can be UNSTABLE...
if ir is cooler than the surface beneath it
The strength of a thunderstorm is related to HEIGHT, which means...
infrared imagery can be used to establish a storm's potential to produce severe weather
Heat is the transfer of energy that fuels atmospheric processes, while temperature...
is used to measure and interpret that energy
If the conditions are right and the air mass rises rapidly...
it can produce clouds associated with thunderstorms
Airmass
large body of air that takes on the characteristics of the area over which it forms - can be described by its stability, temperature, and humidity
Jet streams
narrow bands of fast, high altitude, westerly winds -flow at speeds up to 185 km/h at elevations of 10-12 km -disturbances form along jet streams -gives rise to large scale weather systems that transport cold air toward the tropics, and warm air toward the poles
The sun's rays are more spread out when they strike the earth at a...
low angle - solar radiation at the poles is less intense - explains why the tropics are warmer than the poles
Meteorologists
measure the atmospheric variables of temperature, air pressure, wind, and relative humidity in order to make accurate weather forecasts
barometer
measures air pressure using mercury -changes in air pressure are indicated by changes in the height of a column of mercury
hygrometer
measures relative humidity
ceilometer
measures the height of the cloud layers and estimates the amount of sky covered by clouds
Trade winds
occurs at 30 degrees north and south latitude -the air sinks, warms, and moves toward the equator in a westerly direction - Near the equator, the trade winds from both hemispheres converge and are FORCED UPWARD, creating an area of low pressure called the inter-tropical convergence zone (ITCZ)
Everything we consider weather is...
part of the constant redistribution of Earth's heat energy
Temperature is directly proportional to...
pressure
Temperature varies with changes in both...
pressure and density - the ratio of pressure to density decreases with higher altitudes
Carbon dioxide and water vapor...
regulate the amount of energy the atmosphere absorbs
The sun is always...
shining and warming some portion of the Earth's surface, this is through the transfer of radiation
condensation nuclei
small particles in the atmosphere around which cloud droplets can form -sea salt and dust are condensation nuclei
Satellites track clouds while cameras...
take photos of the earth at regular intervals
Dew point
temperature at which air is saturated and condensation forms
coalenscence
the cloud droplets collide, they come together to form a larger droplet - becomes to heavy to be held aloft and falls to earth as precipitation
Weather
the current state of the atmosphere - usually refers to short term variations -long term variations in weather for a particular area is climate (30 year period)
Coriolis effect combines with imbalances in heat to create...
the global wind systems -transports colder air to warmer areas and warmer air to colder areas
A front
the narrow region separating 2 air masses of different densities
Saturation
the point at which air holds as much water vapor as it possibly can -until air is saturated, condensation cannot occur
relative humidity
the ratio of water vapor in the air relative to how much water vapor that volume of air is capable of holding - varies with temp. - because warm air is capable of holding more moisture than cool air - expressed as a % - if a volume of air is holding the max amount of water vapor, the relative humidity is 100%
Meterology
the study of atmospheric phenomena
Heat
the transfer of energy that occurs because of a difference in temperature between substances -direction of heat flow depends on temperature
the air moves in response to density imbalances created by...
the unequal heating and cooling of earth's surface
Convection currents
the upward movement of warm air and the downward movement of cool air - one main mechanism responsible for the vertical motions of air which in turn cause the different types of weather.
Some satellites use infrared imagery...
to detect differences in thermal energy, which are used to map cloud cover or surface temperatures
Convection
transfer of energy by the flow of heated matter - as warm air rises, it expansionists as it starts to cool - when it cools enough, it begins to sink because it increased with density
Both temperature and pressure generally decrease with height in the troposphere.
true
If the amount of moisture in the air remains the same and the temperature rises, the relative humidity will decrease.
true
The density of air increases as altitude decreases.
true
wave cyclone
type of low pressure system -usually begins at a stationary front -an imbalance causes part of the front to move south as a cold front, and another part to move north as a warm front. - this sets up for a counter clockwise cyclonic circulation
Electrometers
visible or audible manifestations of atmospheric electricity - thunder and lightening
warm front
warm air gradually displaces cold air, creating clouds and showers
stationary front
when 2 air masses meet and neither is displaces, causes long periods of rain
occluded front
when a cold air mass takes over a warm front, wedging it upward, creates precipitation on both sides of the front
air mass modification
when an air mass travels over land or water that has different characteristics than those of its source region, it undergoes -eventually, an airmass's characteristics are the same as the are surface over which it is traveling -at this point, the air mass has lost it's original identity and is now apart of the air over a new source region
How do clouds form?
when warm, moist air rises, expands, and cools in a convection current
Scientists combine data from radar and satellites to determine...
where both clouds and precipitation are occurring
Winds are named from...
which direction they blow