Meteorology Ch 7

Terms in this set (39)

microscale winds

small, chaotic winds that last for seconds or minutes (dustdevils, wind gusts, microbursts)

mesoscale winds

winds that generally last several minutes, and sometimes exist for hours (tornadoes, thunderstorms, local winds: land/sea breeze, Santa Ana)

macroscale winds

divided into 2 categories (planetary-scale and synoptic-scale); (midlatitude cyclones, anticyclones, hurricanes, westerlies, trade winds)

planetary-scale

(westerlies and trade winds that carried vessels back and forth across atlantic) large-scale flow patterns that extend around the entire globe and can unchained for weeks at a time

(weather-map scale); about 1000km in diameter and easily identified on weather maps (midlatitude cyclones and anticyclones); mainly in mid-lats

cooler are over water moves landward toward area of lower pressure

usually at night land cools more rapidly and formed with airflow off the land

warmer air glides up the mountain slope; cumulus clouds typically develop over adjacent mountain peaks causing late afternoon t-storms

mountain breeze

rapid heat loss along slopes cools air that then drains into the valley, causes wind

warm, dry winds, sometimes move down slopes of mountains in USA

(chinooks but in Alps) warm, dry winds, sometimes move down slopes of Alps; both created when strong pressure gradient happens

chinook-like wind in USA; in southern Cali, dry and hot winds increase threat of fire

katabatic wind (fall wind)

cold dense air situated over highland area (ice sheets of Greenland/Antarctica) begin to move; cold air cascades like a waterfall (because of gravity)

blows from French Alps toward Mediterranean Sea (famous katabatic)

origin in Balkan Peninsula and blows to Adriatic Sea (famous katabatic)

large urban areas, light wind blowing into the city from the surrounding countryside

zone between equator and roughly 30 degrees lat N and S; resembles convection model; air rises from equator and sinks as it gets to edges of lat causing circulation

horse latitudes

between 20 and 35 degrees where winds are weak

equatorward flow deflected by Coriolis force forms these; allowed ships to move goods between Euro and America

where trade winds meet (near equator); region with weak pressure gradient causing monotonous weather

between 30 and 60 degrees; made to account for westerly surface winds in middle lats

prevailing westerlies

in North America, winds go from west to east

driven by subsidence near poles that produces a surface flow that moves equatorward

polar easterlies

winds move east to west

region where flow of cold air clashes with flow of warm area

low-pressure zone; ascending moist, hot air causes lots of precip

intertropical convergence zone (ITCZ)

visible as a band of clouds near equator, low pressure region where trade winds converge

subtropical highs

high pressure zones, 20-35 degrees on either side of equator where trade winds/westerlies originate

where polar easterlies and westerlies clash in low-pressure convergence zone

at Earth's poles, where polar easterlies originate, result from surface cooling

very strong, high-pressure center over frozen landscape of northern Asia; most prominent feature in January pressure map

Bermuda/Azores high

center of subtropical high

cyclone over north pacific (low pressure)

cyclone over north atlantic

fast streams of air; occur near top of troposphere with winds that can reach almost 240mph (400km/h)

polar jet stream

jet stream that occurs along the polar front

subtropical jet stream

mainly wintertime phenomenon; slower that polar jet, at 25 degree lat

nearly circular ocean currents

rising of cold water from deeper layers to replace warmer surface water (wind-induced

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