alpenglow a peak's rosy glow before sunrise or just after sunset.
alpenhorn a very long, wooden horn used to convey signals in the Alps or other mountainous regions.
alpine any lofty or towering mountain comparable to an alp. Also used to describe the elevation above 4,800 feet, where vegetation grows in a stunted fashion or not at all.
alpinist a mountain climber.
avalanche a dangerous fall or slide of a large mass of snow, ice, or rocks down the side of a mountain.
avalanche wind a powerful and sometimes dangerous wind generated by an avalanche.
banner cloud a stationary cloud seen frequently over the lee side of some mountains, such as the Mat- terhorn.
basin a U-shaped bowl created by a glacier.
butte a steep-sided mountain usually having a level top.
cairn a trail marker built of piled rocks, often used near summits.
cirque a large bowl-like or amphitheater-like hollow in the side of a mountain, carved out by snow, ice, and glacier activity.
col a saddle or low pass between two summits.
cordillera a group of parallel mountain ranges.
cornice an overhanging mass of snow or ice; it resembles an ocean wave and is known to collapse and cause avalanches.
couloir a deep. wide gully that acts as a funnel for falling snow, ice, or rocks. Also known as a coulee.
crag a steep and weathered mass of rock.
dome a type of mountain formed by the upwelling of molten rock through a crack in the Earth, causing surface mounding or bulging; when the surface crust is eventually eroded away, a dome of hardened lava remains.
escarpment a sheer cliff, a scarp.
faulted block mountain mountain formed by a massive uplifting of the Earth.
folded mountain a geological term describing a mountain formed by corrugation and compression of the Earth.
glacial erratics boulders left by glaciers that differ from native rocks, frequently seen near mountainous areas.
flank the side of a mountain.
hogback any sharp ridge or ridges with steeply sloping sides.
inselberg a vestigial mountain reduced by erosion to a rocky nubbin or isolated "island," found in ancient desert areas.
Krumholz "crooked wood"; the stunted vegetation caused by severe cold and wind at high elevations. The Krumholz zone is found wherever alpine vegetation has been twisted and dwarfed by the elements, usually above 4,800 feet.
massif a mountain that forms a mass of peaks.
matterhorn a sharp, steeply descending peak, usually formed by glacial erosion.
monadnock a massive rock that has resisted erosion better than surrounding rock and therefore remains standing as a large hill or small mountain.
mountain sickness an illness brought on by oxygen deprivation at high altitudes; the symptoms include headaches, nausea, and general weakness.
nunatak a mountain surrounded by glacial ice.
oread in Greek mythology, a mountain nymph.
orography the study of mountains.
piedmont pertaining to the foot of a mountain, as a piedmont glacier.
pinnacle the top or peak.
piton French term for a pointed peak.
plateau an elevation with a broad, flat top; mesa; tableland.
rain shadow the leeward side of a mountain, which receives far less rain than the windward side.
rarefied of or relating to the thinner air supply at high elevations.
ridgeback the lengthwise crest of any ridge.
rime ice a freezing fog found at high altitudes that settles on rocks and vegetation. Also known as verglas.
saddle the lowest point between two summits.
scree loose slopes of rock fragments and boulders.
seamount a mountain under the sea.
shoulder a humpback or false ridge.
sierra a mountain range or chain.
skirt the skirting of trees around the mountain below the alpine line.
specter of the brocken greatly enlarged shadow of a climber seen projected on a cloud or mist near a summit; named after a peak in Germany.
spur a lateral ridge projecting from a mountain.
table mountain a mesa, plateau.
talus collective term for the boulders, rocks, and gravel fragments often found at the base of cliffs and steep slopes.
tarn a mountain lake, often occupying a cirque.
tundra the barren area where little vegetation grows, above 4,800 feet.
ubac French term for the side of a mountain that is coldest because it receives the least amount of sunlight.
precipitation
acid rain rain or snow containing high levels of sul- furic or nitric acids, which are produced by fossilfuel- burning industry and internal combustion engines, and have been shown to damage vegetation, foul drinking water, and intensify erosion of buildings and other outdoor structures.
arid describing any area that is very dry and tends to lack precipitation of any kind.
blizzard any storm characterized by steady winds of at least 35 miles per hour (56 km/hr) with heavy snowfall that sharply reduces visibility and lasts for three hours or more.
condensation the change of a substance from a vapor to a liquid; the opposite of evaporation.
corn snow that has melted and refrozen to form a rough, granulated surface.
dew point temperature at which air becomes saturated; a further drop in temperature causes condensation followed by precipitation.
downdraft a column of cool air that rapidly descends to ground level, usually accompanied by precipitation.
evaporation the dispersal of moisture from surface water into the atmosphere.
firn old, compacted, and hardened snow; with further compacting it becomes glacial ice.
graupel falling pellets of snow; also known as soft hail.
humidity moisture content of the air.
hydrologic cycle the process of maintaining a constant water vapor content in the atmosphere by surface evaporation of oceans, lakes, rivers, and moist soil, and by transforming such moisture into a precip- itable form. The three phases of the hydrologic cycle are evaporation, condensation, and precipitation.
hydrometeors collective term for all types of precipitation.
hyetography the study of rainfall.
hygrometer a device for measuring the amount of humidity in the air.
lake effect snow a heavy snowfall caused by cold, arctic air passing over a large expanse of warmer lake water and pulling up water vapor, freezing it, and turning it into snow, most notably occurring over the U.S. Great Lakes.
precipitation classification drizzle—fine droplets barely reaching the ground before evaporation; mist—fine droplets that usually evaporate before reaching the ground; hail—frozen droplets produced from violent convection in thunderstorms; sleet—frozen rain; rime—freezing fog.
rain gauge a device for measuring the amount of precipitation in a given time period.