Weather and Climate Ch8

the largest-scale patterns, the background against what unusual events occur

a simple circulation pattern, describes th egeneral movement of the atmosphere

winds blowing east to west or west to east

winds moving north to south or south to north

a more elaborate model used to describe the general atmosphere that divides the circulation of each hemisphere into three distinct cells (Hadley cell, Ferrel cel, and polar cell)

circulates air between the tropics and subtropics

circulates air in the middle lattitudes

circulates air around the poles

A zone of low pressure around the equater created by strong solar heating, wich causes air to expand upward and diverge toward the poles.

When air in the Hadley cell sinks toward the surface it forms subtropical highs, which are large bands of high surface pressure.

the point at which horses were thrown overboard from ships crossing from Europe to the New World in order to not get stranded.

winds deflected slightly to the right by a weak coriolis from the subtropical highs

In the southern hemisphere, the northward-moving air from the subtropical high is deflected to the left to create the southeast trade winds

areas of low pressure

a wind belt created by air going poleward undergoing a substantial deflection to the right

low-level anticyclones of the arctic and antarctic

low-level winds originating in the polar highs

high and low-pressure cells that undergo seasonal changes in position and intensity throughout the year

cells over the Pacific and Atlantic Ocean

cell over central Asia

cells over Pacific and Atlantic oceans

cell over southern Asia

a boundary between warm and cold air

maintains the temperature contrast across a front, a consequence of a polar front, like a river of air

jet stream near the equator, associated with the Hadle cell

waves are wavelike flows of air caused by ridges and troughs... Rossby waves are long waves

horizontal movements of surface water often found around the rims of major basins

An ocean current pattern in which 100m below the surface the direction of the current approaches 180 degrees to the directionof the wind, and thus dies out.

Just north of the equator, the easterly trade winds drag the surface water westward to form the North Equatorial Current

Just south of the equator, easterly trade winds drag the surface water westward

the water from the north and south equatorial currents converges and piles up in the western equatorial Atlantic and forms the eastward-moving Equatorial countercurrent

In the Northern Hemisphere, most of the North Equatorial Current reaching the South American coast turns northward to form the Gulf stream

Near 40 degrees N., the westerlies force the current to the east, forming the North Atlantic Drift (as opposed to the Gulf Stream)

The North Atlantic Drift eventually cools to become the cold Canary Current as it turns southward

the cold current that flows southward along the Maritime Provinces of Canada

feeds the Labrador Current along the Maritime Provinces of Canada

strong offshore winds (from land to ocean) drag warmer surface waters seaward, which draws up cooler waters from below to take their place

large-scale features of the atmosphere

features that cover hundreds or thousands of square kilometers (smaller than global scale features) operate from days to a couple weeks

smaller features than both global scale and synoptic scales, consists of elements covering tens of square kilometers and last as breif as half an hour

the smallest exchanges of mass and energy scale

the climatic pattern in which heavy precipitation alternates with hot, dry conditions on an annual basis

areas of low pressure superimposed in the southeasterly air flow out of Bay of Bengal.

generic name for synoptic scale winds that flow down mountain slopes, warm by compression, and introduce hot, dry and clear conditions to the adjacent lowlands

winds warmed by compression that descend the eastern slopes of the Rocky Mountains

develop (in California) when high pressure develops over the Rocky Mountains, the descends the western slopes and are warmed by compression.

originate when air is locally chilled then flows down slopes and is warmed (unlike foehns and chinooks, which are cooled by migration of weather systems)

the air from water moves toward low-pressure area over land (remember, winds are always named after the direction from which they blow)

a distinct boundary between the cooler maritime air and the continental air it displaces

when the land surface cools more rapidly than the water at night, the air over the land becomes dense and creates a land breeze.

much like sea and land breeze circulations, but with lakes

air flows up from valleys to replace the warm air on top of slopes that expand outward

at night, mountains cool more rapidly than low-lying areas, so the air becomes denser and sinks into the valleys to produce mountain breeze

recurrent event in the tropical Eastern Pacific in which sea surface temperatures are significantly above normal

east-west circulation pattern of the tropics

the change in sea surface conditions linked with the change in the atmospheric pressure distribution

the combined occurrence of El Nino and Southern Oscillation (because they are closely intertwined)

(opposite of El Nino) below normal sea surface temperatures exist in the tropical eastern Pacific

the monthly sea-level departure from normal at Tahiti minus the departure from normalk at Darwin, Australia.

the relationship between weather or climate patterns at two widely separted locations

a pattern in which two nodes of sea surface temperature exist (a large on in the norther and western part of the basin and a smaller one in the eastern tripical Pacific)

The multiyear oscillations of the Atlantic