Chapter 6 - Atmosphere-Ocean-Cryosphere Interactions Flashcards
Albedo
The proportion of incident light reflected by the surface of a celestial body.
What are the three main factors responsible for oceanic movement?
1) winds moving over the top surface.
2) spatial variations in the density of water
3) the Coriolis Effect
SST
Sea-Surface Temperature
PDO
Pacific Decodal Oscillations
PDO Cool Phase
Cooler SST in eastern Pacific to the North, near Alaska
Warmer SST in eastern Pacific mid-north
PDO Warm Phase
Opposite of PDO cool phase
Shifts in PDO are accompanied by what changes?
1) changes in wind direction
2) changes in air pressure
Differences in _____ of water, which is largely a function of temperature and salinity, can set water in motion. Once the water is in motion, its path is deflected by the _____ _____.
density, Coriolis Effect
Wind blowing across a body of water causes water motion via …
1) waves, on the small scale
2) water currents, in the global scale
Null Point
At about 100m below the surface, the effects of wind on the surface vanish (due to viscosity)
Coriolis Effect
The tendency to rotate due to decreasing linear velocity while traveling away from the equator.
Apparent deflection to the right ..CW?.. when North of Equator
Ekman Spiral
….
Horse Latitudes
….
Doldrums
….
Gyres
Interacting circular motions that approximate the direction of near surface currents
Indian Ocean currents
1) the warm Mozambique current flowing south, east of Africa
2) the cool Western Australian current flowing north
3) the warm, lateral current from the Pacific
4) ineractions with the cold Antarctic Circumpolar Current
Western Pacific currents
Kuroshio Current
North Pacific Current
East Australian Current
West Wind Drift
Northern Atlatic Currents
Gulf Stream
North Atlantic Drift
Canary Current
Southern Atlantic Currents
Benguela Current
Brazil Current
Antarctic Circumpolar Current
Northern Pacific Currents
California Current
Alaska Current
Bering Current
Arctic Currents
Bering Current
Labrador Current
Greenland Currents
Southeastern Pacific Currents
West wind drift
Humboldt (aka Chile or Peru) current
South equatorial current
Southern Ocean Currents
Antarctic Circumpolar Current
Antarctica
Roaring forties, screaming sixties, West Wind Drift
Upwelling
Flow of cold, deep waters towards the surface
Cation
A positively charged ion
Anion
A Negatively charged ion
What effect does salinity have on density?
An increase in salinity is proportional to an increase in density
Higher densities sink
Salinity is also affected by temperature
How does salinity decrease?
How does it increase?
Precipitation dilutes the water
Rivers & runoff dilute water
Polar ice melts and dilutes water
Water evaporates, salts don’t
Water freezes, salts don’t
PDO Index
Statistical comparison, the difference between Eastern and Western Pacific SST
What forms of ice occur in the oceans?
1) Icebergs
2) Sea Ice
Overturn (aka turnover)
When shallow waters mix with deeper waters and vise versa.
When waters of different depths have similar temperatures and densities, they mix more easily
AAW
Antarctic Intermediate Waters -
AABW
Antarctic Bottom Waters -
NADW
North Atlantic Deep Waters -
Warm Pools
Recurring areas of water warmer than surrounding waters
Ex: Western Pacific wp, Western Atlantic wp
brine
Highly saline waters at great depths
brine exclusion
The freezing of seawater without saline
Cryosphere
The parts of the planet, collectively, that are frozen or iced over
Photic Zone
The upper depths of the ocean (above the null point) where waters are warmer and less dense.
Thermocline
The boundary between warmer waters and the colder, more dense waters below
Pycnocline
The marked vertical gradient in water density
Thermopycnocline - pycnocline that coincides with the thermocline
Abyssal Waters
The polar waters (cold, dense, highly saline) that descend and then slowly flow back toward the equator
Thermohaline Conveyor
The global flow pattern of surface and deep water circulation
Pg195
Walker Cell Circulation
…IMPORTANT?
Evapotranspiration
….
ENSO
The proper name of El Niño which has two components
1) oceanic activity of El Niño, EN-
2) the atmospheric activity of the Southern Oscillation, -SO
Southern Oscillation
…
SOI
Southern Oscillation Index -
What are the phaes of ENSO?
Neutral Phase: not deemed
Warm Phase:
Cold Phase:
The steps that take place to farm a Kelvin Wave, associated with El Niño
- Easterly trade winds blow water towards the west
- Water piles up in the Pacific Warm Pool, forming a mounded surface
- Easterly trade winds weaken
- The mound flows toward the east as a wave
List two early clues that ENSO has started
- Temporary weakening of the trade winds just east of the IDL at the start of the warm phase
- An increase in atmospheric pressure occurs in the westernmost Pacific relative to locations farther east in the Pacific
What conditions are associated with La Niña?
- Walker Cell circulation strengthens over the equatorial Pacific
- Upwelling off the coast of South America Strengthens
- The warm pool is pushed westward towards Australasia
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