Syracuse University EAR 111 Exam 1
What type of radiation comes from the Earth?
longwave radiation: thermal infrared (heat energy)
Western boundary currents
- Concentrated, narrow northward moving currents - Bring warm water from the tropics to higher latitudes
Radiation absorption diagram
- Water vapor absorbs the widest range of wavelengths. - The most effective wavelength to insert a new greenhouse gas would be between 8-15um.
Eastern boundary currents
- Wide, slower-moving currents that move south along the eastern edges of ocean basins - Bring cool water from high latitudes and encourage upwelling
What is happening to CO2 in the post-industrial era?
- burning 2 billion tons of coal a year; when added with oxygen, it adds 7 billion tons of CO2 to the atmosphere yearly - makes air a more effective blanket for the earth and raises its temperature -predicted the effects would be considerable in a few centuries
Gyres
A large-scale pattern of water circulation that moves clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere
Why is the ocean salty?
Because any erosion of minerals that occurs as the water runs to the ocean, will add to the mineral content of the water. When water evaporates from the ocean, it leaves minerals behind
How do Eastern and Western boundary currents relate to gyres?
Currents at the edges of the gyres are called boundary currents
Why is there a general circulation of Earth's atmosphere?
Earth's atmospheric circulation exists as a result of differences in incoming energy across Earth's surface
winds drawn on a map
Easterlies along equator, westerlies closer to poles
How are Eastern and Western boundary currents' temperature structure different?
Eastern: Bring cool water from high latitudes Western: Bring warm water from the tropics to higher latitudes
Coupling Diagram
Ex) Sign of Feedback (-1) x (+1) = -1, negative feedback
What is a coupling?
Flow of information/mass/energy from one component of the system to another
Why do greenhouse gases warm the atmosphere?
Greenhouse gases reabsorb and re-emit long-wave radiation coming from the Earth, increasing the total radiation coming into earth
Why does deepwater form?
Higher temperature deep water that is a little less dense flowing above colder water; this creates two distinct layers
Negative buoyancy
If a parcel is more dense than surrounding water; moves downward
Positive buoyancy
If a water parcel is less dense than the surrounding water; moves upward
Is the ITCZ exactly on the equator?
No, just North of the equator
Where does deep water form?
North Atlantic
Direction of spin of cyclones and anticyclones in Northern and Southern hemisphere
Northern: inwards/counterclockwise (cyclones) Southern: outwards/clockwise (anticyclones)
How do we know if a coupling is positive or negative?
Positive coupling: change in same sense Negative coupling: opposite sense of change
Ekman spirals
Shows that as we move down through a water column, the surface water moves 45 ∘ from the wind due to the Coriolis force. The next layer moves 45 ∘ from the layer above, but the stress on it is a little smaller, and so on.
What is the thermohaline circulation?
Sinking of salty, cold (dense) waters and upwelling in other regions (from Ekman transports)
Why is Venus so warm?
The dominant gas on Venus is CO2 which absorbs and emits infrared radiation
What is the ITCZ?
The intertropical convergence zone is where converging air masses meet near the thermal equator
How do pycnocline, halocline, and thermocline work together?
Thermocline + Halocline = Pycnocline
What are the westerlies?
Winds that blow from west to east -flow along lines of pressure in the upper troposphere, with a maximum at mid to upper levels -referred to as jet streams
Hadley Cell
an overturning atmospheric cell in each hemisphere caused by the low-level convergence and upper-level divergence of air
How do we name winds?
by the direction they are coming from
Fundamental forces
gravity, friction, pressure gradient force, Coriolis, buoyancy
Longwave radiation
infrared energy emitted by the earth and the atmosphere.
Density
more salty = more dense less salty = less dense
What is the direction of Coriolis deflection?
northern hemisphere: right southern hemisphere: left
Shortwave radiation
radiation emitted by the sun
Albedo
reflectivity of a surface to sunlight
What type of radiation comes from the sun?
short wave radiation: ultraviolet, visible, and shortwave infrared
Joseph Tyndall
showed that gases including carbon dioxide and water vapor can absorb heat and also that they radiated heat, the physical basis of the greenhouse effect
What drives the formation of deep water?
temperature, density, salinity, and buoyancy
Regions of ocean convergence due to winds
the ITCZ
Regions of ocean divergence due to winds
the equatorial Pacific
Eunice Foote
the first person to scientifically test CO2 as a greenhouse gas, determined CO2 warms the atmosphere and warned of global warming
Thermocline
the part of the ocean with the most rapid change in temperature with depth
Halocline
the part of the ocean with the most rapid change of salinity with depth
Pycnocline
the pycnocline encompasses both the halocline (salinity gradients) and the thermocline (temperature gradients)refers to the rapid change in density with depth.
Convergence
typically causes downwelling; transport into the middle of the basin
Divergence
typically causes upwelling; Net transport is away from the equator.
Downwelling
typically happens at places of convergence;
Upwelling
typically happens at places of divergence;
What is the driver of circulation in the mixed layer?
wind stress, the Coriolis effect, and consequent Ekman transports