Geography Chapter 6
What defining change occurs in the pacific decadal oscillation?
a switch between the warm and cool phase of sst occurs in the eastern Pacific
select the statements below that accurately describe part of the IOD
-air descends over over the western Indian ocean near the coast of africa -air travels east across the surface of the equatorial indian ocean
what are two early lines of evidence indicating the warm phase of ENSO may have started?
-an increase in atmospheric pressure occurs in the westernmost pacific relative to locations farther east in the pacific -there is a temporary weakening of the trade winds just east of the international date line at the start of the warm phase
identify the factors that contribute to the formation of abyssal water
-high salinity -low temperature
identify the ways in which ocean water can become less saline
-melting of sea ice -precipitation -input from rivers and streams
in addition to the amount of insolation received, what other factors influence patterns of sst in the ocean
-ocean currents -the upwelling of cold water -adjacent landmasses
in general, the western side of an ocean will be warmer than the eastern side along the same line of latitude. why is this
-ocean currents move away from the equator on the western sides, bringing warmer water to higher latitudes -ocean currents move cold water toward the equator on the eastern sides of oceans
which of the following changes are likely to take place in the warm phase of enso
-reduced rainfall occurs in the western pacific -increased rainfall occurs in the central pacific
What are the main factors that control the motions of water in the oceans?
-the Coriolis effect -surface winds -spatial variations in the density of water
select that statements below that accurately represent part of the global surface seawater salinity pattern
-the lowest salinities are mostly found at high latitudes, where evaporation is reduced -the highest salinities are found in areas of high pressure in the subtropics
which of the following statements accurately describe part of the surface water circulation in the southeastern pacific ocean
-there is a west flowing segment near the equator called the south equatorial current -the cold Humboldt current flows north along the west coast of south america
identify conditions associated with the cold phase (la nina) of enso.
-walker cell circulation strengthens over the equatorial pacific -the warm pool is pushed westward toward Australasia and Indonesia -upwelling off the coast of south America is strengthened.
order the steps below that take place to form a kelvin wave associated with el nino
1. easterly trade winds blow water to the west 2. water piles up in the pacific warm spot 3. the easterly trade winds weaken 4. the mound in the warm pool starts to flow to the east
the combined global scale flow of surface and deep water is called the ____.
Thermohaline conveyor
which of the following accurately describes the change of climatic conditions between winters and summer for the pacific coast of costa rica
a rain shadow forms in winter and strong rains return in summer as the itcz and cross equatorial westerlies bring nearly daily rain
the net transport resulting from the Ekman spiral is ___
at an angle to the surface winds
an atom that loans an electron and ends up with a positive charge is called an ____ whereas an atom that gains the electron and ends up with a negative charge is called an ___.
cation; anion
in an ocean current is moving energy out of an environment, it is a ___ current, but if it is bringing energy to an environment, it is a ___ current.
cold; warm
how does the density of water change as salinity increases
density increases
differences in the ___ of water, which is largely controlled by temperature and salinity, can set water in motion. once the water is in motion, its path is deflected by the ____ effect.
density; coriolis
rank the phases of enso in terms of sst in the equatorial eastern pacific
el nino neutral la nina
ocean currents move warm water poleward. this happens because ____.
energy is moved from areas of energy excess to areas of energy deficit
the linked responses of el nino and the southern oscillation are known by the acronym ____.
enso
the freezing of seawater, ice outflow from glaciers, and additions of snow can all contribute the growth of ___ shelves
ice
the equator-to-pole decrease in the amount of ___ received is the main reason there is a general equator-to-pole decrease in sst
insolation
the equator-to-pole decrease the amount of ____ received is the main reason there is a general equator-to-pole decrease is sst
insolation
as rains falls on the surface of the ocean, the salinity of the surface water decreases. what happens to the density of the surface water?
it decreases
the index that compares sst in the eastern and western pacific is called the ___.
pdo index
why are the warmest sst not always found along the equator
rising air along the equator forms clouds, and they reduce the amount of insolation received at the surface of the ocean
select the statements below that accurately describe global patterns of sst
sst are highest at low latitudes and lowest at high latitudes polar regions have the coldest sst
What is the difference between the warm phase and cool phase of the pacific ocean? the warm phase occurs when ___?
sst are warmer than usual in the eastern pacific and cooler in the mid-pacific, and the cool phase has the opposite pattern
when climatic conditions in one region affect the climatic conditions in a distant region, the associations between the events are called ___
teleconnections
Select the statement below that best summarizes the amount of feedback between the atmosphere and the oceans
the conditions in the oceans are closely tied to the conditions in the atmosphere, and vice versa
what are teleconnections
the links between climatic changes in one region and climatic changes in a distant region
why does el nino eventually start to weaken
the warm pool in the kelvin wave starts to move back to the west, and generally disperses
what is a kelvin wave with respect to an el nino event
the warm pool of water that moves across the equatorial pacific
Select the statement below that accurately characterizes how often the atmosphere and oceans interact.
they interact constantly
When surface waters are blown out away from a coastline, cold water from deep in the ocean can replace the surface water in a process called ____
upwelling
what type of winter occurs in the southern US during El nino conditions
wet and cool