Final Unit Flashcards
What are heating-degree-days
A metric used to estimate the amount of energy needed to heat a space up to a base temperature based on a daily average
What are cooling-degree-days
A metric used to estimate the amount of energy needed to cool down a space to a base temperature based on a daily average
What does N/x mean on a MOS table?
The night time minimum and daily maximum
What does CLD mean on a MOS table?
Cloud cover total in terms of a percentage
What does WDR mean on a MOS table?
Wind direction using degrees relative to true north
What heats faster, land or water surfaces?
Land
Why are northern hemispheres thermal gradience more drastic than the southern hemisphere
The northern hemisphere has more land
What is continentality?
The effect of an inland location that favors greater temperature extremes
What time is it in Arizona if UTC is 1400?
2 AM
Why does water heat less?
Greater specific heat, transparency, evaporative cooling, horizontal and vertical mixing
What are all the influences on temperatures?
Altitude and elevation, Contrasts between land and water, warm and cold ocean currents, local conditions
What is the Bowen Ratio?
The ratio of sensible to latent heat loss from a surface
How is pressure measured?
Millibars (mb) or pascals (Pa)
Is the pressure decrease in altitude proportionate? why?
NO, this is due to compressibility, as altitude increases, the air gets less dense, so each additional meter of height results in a smaller decrease in pressure.
What is a barometer?
Any instrument that measure temperature
What is the standard barometer?
An inverted tube filled with mercury, the greater the pressure the higher the mercury
What is an Aneroid Barometers?
A gauge attached to a lever that reacts to a compressible chamber expanding or compressing depending on the air pressure
What is a barograph?
An aneroid instrument that plot continuous values of pressure
What is the equation of state, or the ideal gas law
PV=nRT
What do pressure gradients produce?
Wind (from high to low pressure)
what is a jet stream
Narrow fast-moving wind band in typically troposphere
what is a jet streak
a segment of a jet stream that is significantly higher wind speeds than others
What is the partial pressure law called?
Dalton’s Law of Partial Pressures
Due to the Coriolis effect what direction do atmospheric objects tend to curve in the Northern hemisphere
Right
Due to the Coriolis effect what direction do atmospheric objects tend to curve in the Southern hemisphere
Left
What is the equation for the magnitude of the Coriolis force
Fc = 2 * Ω * ν * sin(φ)
Where is the Coriolis force the strongest
At the poles
Where does friction affect wind speed
In the Planetary Boundary Layer ( first 1 mi of surface ) otherwise it is negligible
What is pressure gradient force?
The force that causes fluids and gases to go from high pressure to low pressure
What is geostrophic flow
The balanced horizontal (parallel to isobars) flow of wind then the Coriolis force and the pressure gradient force even out due to the increasing Coriolis force as the wind picks up speed
What is gradient flow
When flow changes direction and
height contours curve and flow remains parallel to contours
Why are near winds at the surface not parallel to isobar lines?
Because it suffers friction, geostrophic flow can only occur on large scales where friction is negligible
What is formed as a result of low pressure centers?
Cyclones
What direction do cyclones spin in the northern hemisphere?
Counterclockwise
What direction do cyclones spin in the southern hemisphere?
Clockwise
What direction do anticyclones spin in the northern hemisphere?
Clockwise
What direction do anticyclones spin in the southern hemisphere?
Counterclockwise
What direction does air go in a cyclone?
Up
What direction does air go in an anticyclone?
Down
What is supergeostrophic flow?
Air moving faster than geostrophic flow due to centripetal forces working with pressure gradient forces
What is subgeostrophic flow?
Air moving slower than geostrophic flow due to centripetal forces working against pressure gradient forces
What is a trough?
An elongated low pressure area
What is a ridge?
An elongated high pressure area
Where do cyclones and anticyclones happen in the atmosphere?
Near surface
Where do troughs and ridges happen?
Upper atmosphere
What gives way to troughs and ridges in the upper atmosphere?
Cyclones and anticyclones in the lower atmosphere
What is hydrostatic equilibrium?
Vertical pressure gradient force is
equal and opposite to the gravitational force
Why will pressure drop quicker in colder air?
The air is denser so as you go up there is increasingly less air above you to put pressure on you
What is Transpiration?
Transfer of water through plants
What is interception?
precipitation that falls onto vegetation and accumulates
as a coating on leaf surfaces, cactus needles
What is infiltration?
Water (from precipitation) may collect along the surface or
penetrate into the ground and collect within the soil column
What is Vapor pressure?
the amount of pressure exerted on the
atmosphere by water vapor
What is Saturation vapor pressure?
the vapor pressure of the
atmosphere when it is saturated
What is Absolute humidity?
the density of water vapor expressed
as the number of grams of water vapor per cubic meter of air
What is Specific humidity?
represents a given mass of water
vapor per given mass of total air
What is Saturation specific humidity?
the specific humidity of
the atmosphere when it is saturated
What is Mixing ratio?
represents a given mass of water vapor
per given mass of dry air
What is Relative Humidity?
the amount of water vapor
relative to the maximum that can exist at a particular
temperature
What is dew point temperature?
the temperature at which saturation occurs in the air and
is dependent upon the amount of water vapor present
