weather vs climate
- weather is over a short period of time
- - constantly changing
- climate is over long period of time
- - generalized, composite of weather
6 elements of weather and climate that are measured regularly
-winds speeds and direction
amount of sunlight it reflects
-makes most of our atmosphere
- Nitrogen: 78%, Oxygen: 21%, and Argon;other gases: <1%
-make up small percent of our atmosphere
- it can affect our physical comfort.
- water vapor, carbon dioxide, ozone, and methane
density of atmosphere
-its more denser the nearer one is to sea level. it gets thinner as you go higher
Structure of atmosphere by function
Ozonesphere and Ionosphere
(atmosphere by function) Ozonesphere
blocks UV radiation
(atmosphere by function) Ionosphere
-blocks ions (solar wind)
-source of Aurora
structure of atmosphere by temperature
(structure of atmosphere by temperature) troposphere
-temperature decreases by altitude
- called the enviromental lapse rate
- -6.5 C/ 1000 m
- 3.5 F/1000 feet
-outer layer tropopause
(structure of atmosphere by temperature) Stratosphere
-about 12 km to 50 km
- temperature increases at top
-absorption of UV radiation
-outer layer stratopause
(structure of atmosphere by temperature)
- about 50 km to 80 km
- temperature decreases
- outer boundary is named mesopause
- absorption of solar radiation near the base of it, provides the heat layer
(structure of atmosphere by temperature) Thermosphere
- no well-defined upper limit
- fraction of amosphere's mass
-gases move at high speeds
-believed to have formed same time as planet
-Hydrogen and Helium
-earth was too small to keep lighter, smaller gases
- may have been blown by collisions
secondary atmosphere main gases
Main gases: H2O and CO2
small amounts: SO2, N2
changes to secondary atmosphere...
volcanic eruptions and comet collsions: made H20 and CO2 become inferior gases opposed to be main ones.
the amount of water vapor in the air.
Relative humidity: amount of water vapor present relative to the maximum water vapor that can be held (saturation)
-cloud cover and albedo
-clouds absorb heat at night
(Temperature controls) Geographic position
- - influence of mountains
- - act as a barriers
- can cut inland areas off from warming ocean winds
(Temperature controls) Cloud cover and Albedo
- clouds reflect incoming solar radiation during the day
-albedo is high then temps are cool
(Temperature controls) Clouds absorb surface radiation at night
- heat radiated back to surface, warming effect
-these are driven by the temperature difference between the equatorial regions and the poles.
-wind is used a way to balance temperature in Earth
3-cell model of global winds
-it is the model that we are currently using to describe global circulation
(3-cell model) Hadley cell
is a single wind system in each hemisphere.
-warm air rises near the equator, cools as it travels poeward at high altitude, sinks as cold air, and warms as it travels equatorward
-in northern hem. objects reflect right
-in southern hem. they deflect left.
objects are deflected acordingly depending on their location. It does this because of Earth's rotation
(3-cell model) horse lattitudes
- winds are generally weak and varied near the center of this zone of descending air
(3-cell model) Trade winds
-blowing from subtropical highs or horse latitudes
- In northern hemisphere they blow northeast and southern hemisphere they blow southeast
(3-cell model) Doldrums
-region in which trade winds from both hemispheres get together.
-low-weak pressure gradient
(3-cell model) Prevailing westerlies
-winds that blow around 30 thru 50 degree latitude on both hemispheres.
- wind blows from west to east
(3-cell model) Polar easterlies
- cold winds that blow through both hemispheres westward direction.
(3-cell model) Polar front
- region where the flow of warm air clashes with cold air.
local winds...what drives them