Exam 2 Flashcards
what are the layers of the atmosphere?
Thermosphere/Ionosphere
Mesosphere
Stratosphere
Troposphere
Ground
Water Cycle: Gas to water
Condensation
Water cycle: Water to gas
Evaporation
Water cycle: liquid to solid
Freezing
Water cycle: Solid to liquid
Melting
Water cycle: Gas to solid
Deposition
Water cycle: Solid to Gas
Sublimation
As solid or liquid water absorbs energy from a source (e.g. Sun), it changes phase through the processes of ______, driving the uphill component of the water cycle.
evaporation, transpiration, and sublimation
Water vapor is often carried great distances before it changes into liquid or solid cloud particles, transporting ______ heat energy from one place to another.
latent
While atmospheric water vapor flow is invisible to our eyes, it is visible to
infrared sensors
The curving swirls of water vapor in the middle latitudes of the Northern and Southern Hemispheres reveal winds transporting water vapor horizontally over great distances. In the middle latitudes, the dominant horizontal motion in both hemispheres is from ______
West to east
In the southeastern U.S., the amount of water vapor in the air is high during the summer, but that water vapor still exerts only about 3.5% of the total surface pressure. The pressure at the surface is approximately 1000 mb, so the vapor pressure is ______ mb.
35
Absolute humidity definition
the mass of water vapor in a given volume of air, or the density of the water vapor component of air, expressed in grams of water vapor per cubic meter of air.
Absolute humidity formula
Absolute humidity = Mass of Water Vapor/ Volume of air
Relative Humidity Formula
Relative humidity = (vapor pressure/saturation vapor pressure) × 100%
Dewpoint
the temperature to which air must be cooled to become saturated while maintaining a constant pressure.
Convection lifting of air
Hot air rises, cool air sinks
Convergence lifting of air
occurs when multiple surface air currents come together horizontally towards a common point, leading to upward movement as they meet.
Frontal lifting of air
occurs when air masses of different densities, often due to temperature, converge. Colder air displaces warm air, which ascends over the fronts
Orographic lifting of air
occurs when horizontal winds must rise to surpass geographical obstacles like hills and mountains.
Prevailing upper-level winds blow from west to east across the United States. Winds blowing onshore from the Pacific Ocean are forced up the windward slopes of the Cascade Mountain Range in the Pacific Northwest. Hence, the heaviest precipitation falls on the Cascades’ ______ slopes.
Western
latent heating definition
Transport of heat from one place to another within the atmosphere as a consequence of phase changes of water.
Sensible heating definition
Transport of heat from one location or object to another via conduction, convection or both.
As an unsaturated air parcel rises and expands, the temperature will ______ until it reaches the air parcel’s dewpoint, and it becomes saturated. Once saturated, further ascent will cause the air parcel to cool by expansion but also warm as ______ heat is released to the air in the parcel when water vapor condenses into droplets or deposits as ice crystals.
fall … latent
What do the straight lines on the Stuve diagram mean
Dry adiabatic rate or the temperature change in an unsaturated parcel
What do the dashed lines on a stuve diagram mean?
The temperature change from a saturated parcel
How can you tell if there are clouds present on a Stuve diagram?
The right, temperature line and the left, dewpoint line, are within 1 degree of each other, there are clouds (T-DP= <1 = clouds)
If you were given a stuve diagram and it asks you to find the final temp of an unsaturated parcel, how do you figure that out?
Plot the original point, follow the STRAIGHT LINES until you hit the end pressure, drop it down to find what the final temp is
How would you find the final temperature of saturated air parcel?
Follow the trend of the DASHED LINE from the starting temp/pressure to the final pressure and drop it down to the final temp
As our second air parcel rises, assume it becomes saturated at 800 mb. From 1000 mb to 800 mb, it will follow a ______ adiabatic lapse rate line.
dry
As our air parcel continues to rise above the saturation point, it will follow a ______ adiabatic lapse rate line.
Saturated
What is the direction of force when it is the force of attraction between your mass and the mass of the earth?
Downward
The pressure gradient force arises from a change in the air pressure with distance and accelerates air away from regions of higher air pressure and towards regions of lower air pressure. The pressure gradient force is strongest where isobars are
Closest together
Because earth is rotating, horizontal winds everywhere except at the equator are deflected to the right or the left relative to earths surface. This Coriolis effect arises because the air is moving over a surface which itself is continually turning because of Earths rotation. In the Northern Hemisphere, the Coriolis effect causes wind blowing towards the west to turn towards the
Southwest
The deflection of horizontally moving air due to the effect of earths rotation is greatest at the poles where Earths surface makes one complete 360 degree spin around the rotational axis in 24 hours. The deflection is totally absent at the equator because earths rotation does not cause any turning of earths surface around a vertical axis at that location. Hense, the coriolis effect is zero at the equator and _____ as latitude increases
increases
The sense of earths rotation is counterclockwise as viewed from above the north pole and clockwise as viewed from above the south pole. This reversal in the sense earths rotation means the deflection due to earths rotation reverses between the Northern and Southern hemispheres. Hense, air moving horizontally in the northern hemisphere turns to the _____ relative to earths surface, while in the southern hemisphere it turns towards the opposite direction
right
The Coriolis effect varies with the wind speed. If there is no air motion relative to Earths surface (calm conditions), there is no Coriolis effect. As wind speed increases, the Coriolis effect____
increases
Fluid friction arising from large irregular motions within the atmosphere is ______ viscosity
eddy
Hydrostatic equilibrium is the balance between the upward vertical pressure gradient force and the downward force of ______. Imbalances lead to convective motions
Gravity
The figure displaying the evolution of straight, balanced, horizontal flow shows the influence of the Coriolis effect on the air subjected to a horizontal pressure gradient force when neighboring isobars are straight and parallel in the northern hemisphere. At altitudes above the friction layer, the coriolis effect balences the horizontal pressure gradient force and the air flows along a path________ to the isobars. This is called geostrophic wind
Parallel
Where isobars are curved, the centipetal force interacts with the horizontal pressure gradient force and the Coriolis effect to produce winds that follow the same curved paths as the isobars. This is known as the ______ wind
gradient
The gradient wind describes in simplest terms the circulation around centers of high and low pressures at the altitudes above about 1000 m. Viewed from above the Northern Hemisphere, air flows_____ around a high pressure center
clockwise
The combined effects of the horizontal forces causes Northern hemisphere surface winds in lows (cyclones) to spiral counterclockwise and ______ as viewed from above
inward
The atmosphere is a continuous fluid. As surface winds spiral out of the center of the high, more air arrives by decending rom above. The decsending air, in turn, is replaced by air flowing into the system at higher altitudes. As figure 8.19 illustrates, a high (anticyclone) exhibits horizontal divergence of surface winds and horizontal _____ of upper air winds
convergence
The surface pressure in a high can get higher over time if horizontal convergence in the system is _______ that the horizontal divergence
more
The scales of atmosphereic cerculations from smallest to largest
micro, meso, synoptic, planetary
What direction does air move in a low pressure system?
Counterclockwise
On a weather station model, how do you find the temperature?
It is in the upper left corner
On a weather station model, how do you find the dewpoint?
It is in the bottom left corner
On a weather station model, how do you find the sea-level pressure?
Its in the upper right corner
When reading the pressure from a weather station model, if it says 107 how much is it actually?
1010.7
On a weather station model, how do you determine the cloud coverage?
By looking at how complete the circle is. Filled in = complete overcast, partually = partial clouds, and not filled = no clouds
On a weather station model, how do you determine the pressure tendency?
In the bottom right corner there may be a line, from left to right follow its trend. / = continuously rising, reversed = continuously falling, etc
When looking at the wind speed, how much does a thick triangle indicate?
50 knots
On a weather station model, how do you determine if its raining?
There will be dots on the left between temp and dewpoint. More dots = heavier rain
In the mid-latitudes (30–60°), winds blow predominantly from ______. These winds are aptly named the midlatitude westerlies.
West to east
Because the equator receives the most direct solar radiation, it is generally warm, causing the air to ______ and create a zone of low pressure called the intertropical convergence zone (ITCZ), which features light and variable winds (the doldrums), near-constant clouds, and considerable precipitation.
ascend
When the air above the ITCZ reaches the top of the troposphere, it diverges, heading away from the equator. By 30°N and S, it has cooled and ______ within areas of high pressure (subtropical anticyclones) characterized by calm winds, sunny skies, and little or no precipitation.
Descends
________(warm phase) is characterized by a positive SST anomaly equal to or greater than 0.5°C,.
El Nino
________(cold phase) is characterized by a negative SST anomaly equal to or greater than 0.5°C
La Nina
Under neutral ENSO conditions the trade winds blow, shown in Figure 9A-3 as a horizontal black arrow, from ______ at the Earth’s surface across the equatorial Pacific, pushing warm surface waters in the same direction. The warm water in the west promotes atmospheric convection in that region, leading to precipitation.
east to west
The southern polar region around Antarctica has a belt of low pressure near 60°S (the Antarctic circumpolar vortex) instead of subpolar lows. This area looks the most like the idealized planetary-scale circulation model shown in Figure 9A-1. This pattern is due to ______.
the distribution of land masses in the Southern Hemisphere
The thermocline is the transition zone between warm surface water and cold deep water, shown as the blue layer in the ocean of Figure 9A-3. Strong trade winds pile up warm surface waters in the western tropical Pacific so the ocean surface in the western Pacific is higher than in the eastern Pacific. In the eastern tropical Pacific, the thermocline is ______ than in the west.
Shallower
Cold SSTs over the eastern Pacific and warm SSTs over the western Pacific lead to the formation of a massive east-west convection cell called the __________. Rising air over the western Pacific causes intense thunderstorms, while descending air over the eastern Pacific leads to clear skies and fair weather.
Walker Circulation
Under neutral conditions, the atmosphere-ocean interactions that cause the Walker circulation result in surface air pressure being highest in the ______ tropical Pacific and lowest in the ______ tropical Pacific.
eastern…western
In response to changes in the air pressure pattern across the tropical Pacific, the trade winds weaken and even reverse, especially in the western Pacific as shown by the black arrows. No longer piled up in the western Pacific, the warm surface water reverses and flows toward the east, as shown by the white surface currents arrows. Evident in the ocean surface temperature colors, the SSTs in the eastern tropical Pacific are ______ than during neutral conditions.
higher
During La Niña, the east-west pressure gradient increases across the tropical Pacific, causing ______ trade winds than during neutral conditions.
Faster
During the Northern Hemisphere winter, when El Niño is occurring, the U.S. Southeast and Southern Plains are ______ than normal.
wetter and cooler
Jet streams follow the upper-air westerlies, which flow from west to east around the planet in wave-like patterns, reflecting the height changes (topographical ridges and troughs) of constant pressure surfaces. In Figure 9B-1, the westerlies create _______around the globe, the curved lines are winds following the height contours.
Rossby waves
When looking at Rossby waves, the H identifies
the high peak of a ridge axis
When looking at Rossby waves, the L identifies
the lowest part of the through axis
The distance between successive ridge axes, or between successive trough axes, is the
wavelength
West of a ridge axis, wind favors ______ air advection, and winds west of a trough axis favor ______ air advection.
warm…cold
Upper-air winds steer surface pressure systems as well as air masses. A surface cyclone centered to the west of a trough axis and east of a ridge axis will move toward the ______.
southeast
When the Rossby wave flow pattern is zonal, the source region for air over the conterminous U.S. is the Pacific Ocean. On the other hand, when the Rossby wave flow pattern is meridional, the source region is Canada, when winds are from the northwest, or Mexico and the Gulf of Mexico, when winds are from the southwest. Hence, from west to east, temperatures are likely to be more variable with a ______ flow pattern.
meridional
Rossby waves that have large north-south variation are called
meridional flow patterns
air pressure at any altitude above the surface is higher in a warm air column than in a cold air column. Across the polar front, there is a horizontal pressure gradient from the warm side to the cold side. Therefore, as altitude increases, the horizontal pressure gradient and corresponding wind speed ______.
increase
In the Northern Hemisphere, the pressure gradient force along the polar front is directed toward the ______. Given that upper-level winds are generally from the west, the Coriolis force acts toward the ______.
north…south
When looking at a rossby wave map and it asks you to compare pressure surface as latitude increases, what are you looking for?
As latitude increases, how does the number affiliated with the isobars change
