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114-633: Humes Glacier is located in the Olympic Mountains in Olympic National Park , approximately 2.25 miles (3.62 km) southeast of the summit of Mount Olympus . The glacier starts at nearly 6,000 ft (1,800 m) and descends downslope 1.25 mi (2.01 km), terminating at 4,800 ft (1,500 m) above sea level. It was named by members of The Mountaineers climbing club in 1907 for Grant and Will Humes, who were guides, explorers, and pack-train operators. This article about

228-424: A cirque landform (alternatively known as a corrie or as a cwm ) – a typically armchair-shaped geological feature (such as a depression between mountains enclosed by arêtes ) – which collects and compresses through gravity the snow that falls into it. This snow accumulates and the weight of the snow falling above compacts it, forming névé (granular snow). Further crushing of the individual snowflakes and squeezing

342-589: A glacier in Washington is a stub . You can help Misplaced Pages by expanding it . Olympic Mountains The mountains are located in western Washington in the United States, spread out across four counties: Clallam , Grays Harbor , Jefferson and Mason . Physiographically, they are a section of the larger Pacific Border province , which is in turn a part of the larger Pacific Mountain System . The Olympics have

456-820: A consequence of the high precipitation, northern latitude, and cool moderating climate adjacent to the Pacific Ocean. There are about 184 glaciers and permanent ice fields crowning the Olympics peaks. The most prominent glaciers are those on Mount Olympus covering approximately 10 square miles (26 km ). Beyond the Olympic complex are the glaciers of Mount Carrie and others in the Bailey Range , Mount Christie , Mount Queets , and Mount Anderson , however most of these have experienced significant decrease in both length and mass in recent decades, with several disappearing completely in

570-551: A dense moss layer on the forest floor. The rain forests are the wintering grounds for herds of Roosevelt elk and it is thought that browsing by the elk is responsible for the open shrub layer and the dominance of Sitka spruce over western hemlock. The rain forests are just one type of forest found in the Olympic Mountains. Franklin and Dyrness set out 5 forest zones: Sitka spruce, western hemlock, silver fir , mountain hemlock , and subalpine parkland. Other authors include

684-511: A glacier is usually assessed by determining the glacier mass balance or observing terminus behavior. Healthy glaciers have large accumulation zones, more than 60% of their area is snow-covered at the end of the melt season, and they have a terminus with a vigorous flow. Following the Little Ice Age 's end around 1850, glaciers around the Earth have retreated substantially . A slight cooling led to

798-595: A glacier may flow into a body of water, it forms only on land and is distinct from the much thinner sea ice and lake ice that form on the surface of bodies of water. On Earth, 99% of glacial ice is contained within vast ice sheets (also known as "continental glaciers") in the polar regions , but glaciers may be found in mountain ranges on every continent other than the Australian mainland, including Oceania's high-latitude oceanic island countries such as New Zealand . Between latitudes 35°N and 35°S, glaciers occur only in

912-411: A glacier via moulins . Streams within or beneath a glacier flow in englacial or sub-glacial tunnels. These tunnels sometimes reemerge at the glacier's surface. Most of the important processes controlling glacial motion occur in the ice-bed contact—even though it is only a few meters thick. The bed's temperature, roughness and softness define basal shear stress, which in turn defines whether movement of

1026-408: A kilometer per year. Eventually, the ice will be surging fast enough that it begins to thin, as accumulation cannot keep up with the transport. This thinning will increase the conductive heat loss, slowing the glacier and causing freezing. This freezing will slow the glacier further, often until it is stationary, whence the cycle can begin again. The flow of water under the glacial surface can have

1140-404: A large effect on the motion of the glacier itself. Subglacial lakes contain significant amounts of water, which can move fast: cubic kilometers can be transported between lakes over the course of a couple of years. This motion is thought to occur in two main modes: pipe flow involves liquid water moving through pipe-like conduits, like a sub-glacial river; sheet flow involves motion of water in

1254-460: A lower heat conductance, meaning that the basal temperature is also likely to be higher. Bed temperature tends to vary in a cyclic fashion. A cool bed has a high strength, reducing the speed of the glacier. This increases the rate of accumulation, since newly fallen snow is not transported away. Consequently, the glacier thickens, with three consequences: firstly, the bed is better insulated, allowing greater retention of geothermal heat. Secondly,

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1368-505: A part of the Pacific Ocean floor (separate from the Pacific plate) inched eastward toward North America about 35 million years ago and most of the sea floor subducted beneath the continental land mass of the North America plate. Some of the sea floor, however, was scraped off and jammed against the mainland, creating the dome that was the forerunner of today's Olympics. In this particular case,

1482-470: A sixth, Douglas-fir zone. Different plant associations are typical of one or more forest zones. For instance, the rain forest plant association described above is a member of the Sitka spruce forest zone. The Sitka spruce zone is a lowland zone dominated by Sitka spruce and western hemlock. Precipitation is high, winters are mild, elevations are low. This forest zone is typically found at very low elevations on

1596-484: A thin layer. A switch between the two flow conditions may be associated with surging behavior. Indeed, the loss of sub-glacial water supply has been linked with the shut-down of ice movement in the Kamb ice stream. The subglacial motion of water is expressed in the surface topography of ice sheets, which slump down into vacated subglacial lakes. The speed of glacial displacement is partly determined by friction . Friction makes

1710-410: A tremendous impact as the iceberg strikes the water. Tidewater glaciers undergo centuries-long cycles of advance and retreat that are much less affected by climate change than other glaciers. Thermally, a temperate glacier is at a melting point throughout the year, from its surface to its base. The ice of a polar glacier is always below the freezing threshold from the surface to its base, although

1824-450: A varied ecosystem. The Olympic rain forests are composed primarily of Sitka spruce and western hemlock , as are the surrounding lowland Sitka spruce forests, but are distinct in having a relative abundance of groves of bigleaf maple and vine maple , which support large epiphytic communities of mosses, lichens, ferns, and clubmosses; an abundance of nurse logs on the forest floor; a relatively open forest canopy and sparse shrub layer; and

1938-708: Is a function of both elevation and precipitation, particularly the amount of snow that falls each winter. The growing season for trees is relatively short in the higher elevations of the windward Olympics, compared to similar elevations in other mountain ranges, due to the large accumulations of snow that take a long time to melt each year. Subalpine meadows in the Olympic mountains are of 5 types. Heath shrub meadows are dominated by ericaceous huckleberries and heathers. Lush herbaceous meadows are typified by Sitka valerian and showy sedge . Drier areas or those with longer snow cover grow dwarf sedge ( Carex nigricans ) or grass ( Festuca viridis ) meadows. Phlox diffusa typifies

2052-474: Is a mere 35 miles (56 km) from the Pacific Ocean, one of the steepest reliefs globally and accounting for the high precipitation of the area, with an estimated 240 inches (6,100 mm) of snow and rain on Mount Olympus. 140 to 170 inches (3,600 to 4,300 mm) of rain falls on the Hoh Rainforest annually, receiving the most measured precipitation of anywhere in the contiguous United States. Areas to

2166-468: Is a persistent body of dense ice that is constantly moving downhill under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries . It acquires distinguishing features, such as crevasses and seracs , as it slowly flows and deforms under stresses induced by its weight. As it moves, it abrades rock and debris from its substrate to create landforms such as cirques , moraines , or fjords . Although

2280-456: Is above or at freezing at the interface and is able to slide at this contact. This contrast is thought to a large extent to govern the ability of a glacier to effectively erode its bed , as sliding ice promotes plucking at rock from the surface below. Glaciers which are partly cold-based and partly warm-based are known as polythermal . Glaciers form where the accumulation of snow and ice exceeds ablation . A glacier usually originates from

2394-407: Is affected by factors such as slope, ice thickness, snowfall, longitudinal confinement, basal temperature, meltwater production, and bed hardness. A few glaciers have periods of very rapid advancement called surges . These glaciers exhibit normal movement until suddenly they accelerate, then return to their previous movement state. These surges may be caused by the failure of the underlying bedrock,

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2508-496: Is another Pacific Northwest endemic. Slugs are abundant in the Olympic forests, outweighing mammals and birds combined. They thrive in the cool damp shade of the forests. The banana slug is the largest and most conspicuous of Olympic slugs. Northern spotted owl ( Strix occidentalis caurina ) is an old-growth dependent species and is listed as threatened under the Endangered Species Act. The majority of spotted owls on

2622-411: Is because these peaks are located near or in the hyperarid Atacama Desert . Glaciers erode terrain through two principal processes: plucking and abrasion . As glaciers flow over bedrock, they soften and lift blocks of rock into the ice. This process, called plucking, is caused by subglacial water that penetrates fractures in the bedrock and subsequently freezes and expands. This expansion causes

2736-406: Is by basal sliding, where meltwater forms between the ice and the bed itself. Whether a bed is hard or soft depends on the porosity and pore pressure; higher porosity decreases the sediment strength (thus increases the shear stress τ B ). Porosity may vary through a range of methods. Bed softness may vary in space or time, and changes dramatically from glacier to glacier. An important factor

2850-434: Is called glaciology . Glaciers are important components of the global cryosphere . Glaciers are categorized by their morphology, thermal characteristics, and behavior. Alpine glaciers form on the crests and slopes of mountains. A glacier that fills a valley is called a valley glacier , or alternatively, an alpine glacier or mountain glacier . A large body of glacial ice astride a mountain, mountain range, or volcano

2964-416: Is called rock flour and is made up of rock grains between 0.002 and 0.00625 mm in size. Abrasion leads to steeper valley walls and mountain slopes in alpine settings, which can cause avalanches and rock slides, which add even more material to the glacier. Glacial abrasion is commonly characterized by glacial striations . Glaciers produce these when they contain large boulders that carve long scratches in

3078-460: Is dominated by mountain hemlock . It occurs along with subalpine fir from 1,100 to 1,650 metres (3,610 to 5,410 ft) in the Bailey Range; however, the range of this forest type is not extensive and does not extend much west of Mount Olympus, nor is it common in the east. Chamaecyparis nootkatensis|Yellow-cedar is sometimes found in relation to these plants. In the east and other drier areas,

3192-628: Is higher, and the mountains above 5,000 m (16,400 ft) usually have permanent snow. Even at high latitudes, glacier formation is not inevitable. Areas of the Arctic , such as Banks Island , and the McMurdo Dry Valleys in Antarctica are considered polar deserts where glaciers cannot form because they receive little snowfall despite the bitter cold. Cold air, unlike warm air, is unable to transport much water vapor. Even during glacial periods of

3306-412: Is reduced to isolated stands of trees called tree islands, surrounded by subalpine meadows, in the subalpine parkland zone. Variations in substrate, topography, moisture, and snowpack depth and duration determine the vegetation community. Tree islands form on convex topography, which tends to gather less snow and shed it sooner than surrounding level or concave topography. In the west, the subalpine zone

3420-424: Is represented by its largest and longest-lived species, and some of its second and third ranked species as well. Biomass accumulations are among the highest in the temperate forest zones. Dominance of conifers is thought to be a result of the amount and timing of precipitation. The dry summers limit the growth of deciduous trees, such as most hardwoods. Evergreens, such as most conifers, are able to take advantage of

3534-897: Is termed an ice cap or ice field . Ice caps have an area less than 50,000 km (19,000 sq mi) by definition. Glacial bodies larger than 50,000 km (19,000 sq mi) are called ice sheets or continental glaciers . Several kilometers deep, they obscure the underlying topography. Only nunataks protrude from their surfaces. The only extant ice sheets are the two that cover most of Antarctica and Greenland. They contain vast quantities of freshwater, enough that if both melted, global sea levels would rise by over 70 m (230 ft). Portions of an ice sheet or cap that extend into water are called ice shelves ; they tend to be thin with limited slopes and reduced velocities. Narrow, fast-moving sections of an ice sheet are called ice streams . In Antarctica, many ice streams drain into large ice shelves . Some drain directly into

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3648-547: Is the largest carnivore in the Olympics. Their main prey are deer and elk but they also hunt porcupines and insects. They are rarely seen , but are thought to be widespread and relatively common in the Olympics. The mountain goat ( Oreamnos americanus ) is not native to the Olympic Mountains but was introduced for hunting in the 1920s by a coalition of the Forest Service, the Clallam County Game Warden, and

3762-666: Is the only hummingbird in the Olympics. They overwinter in Mexico and southern California, arriving in the Olympics in February or March with the flowering of the Indian plum Oemleria cerasifera . Harlequin duck ( Histrionicus histrionicus ) breeds in fast-moving mountain streams in the Olympics. They spend the rest of the year in coastal waters. Osprey ( Pandion haliaetus ) and bald eagle ( Haliaeetus leucocephalus ) fish in Olympic rivers, nesting in large old trees. Both are relatively common,

3876-413: Is the region where there is a net loss in glacier mass. The upper part of a glacier, where accumulation exceeds ablation, is called the accumulation zone . The equilibrium line separates the ablation zone and the accumulation zone; it is the contour where the amount of new snow gained by accumulation is equal to the amount of ice lost through ablation. In general, the accumulation zone accounts for 60–70% of

3990-567: Is the silver fir zone, up to about 3,900 feet (1,200 m). This zone gets more precipitation, and more of it as snow, than the lower, warmer, drier western hemlock zone. The cold and the snowpack combine to limit growth of lower-elevation plants. On the other hand, silver fir is less drought tolerant and less fire tolerant than either Douglas-fir or western hemlock. Slide alder ( Alnus viridis sinuata ) grows in snow-creep areas and avalanche chutes, along with yellow-cedar . Meadows of thimbleberry also grow in this zone, often intergrading between

4104-402: Is the underlying geology; glacial speeds tend to differ more when they change bedrock than when the gradient changes. Further, bed roughness can also act to slow glacial motion. The roughness of the bed is a measure of how many boulders and obstacles protrude into the overlying ice. Ice flows around these obstacles by melting under the high pressure on their stoss side ; the resultant meltwater

4218-552: Is then forced into the cavity arising in their lee side , where it re-freezes. As well as affecting the sediment stress, fluid pressure (p w ) can affect the friction between the glacier and the bed. High fluid pressure provides a buoyancy force upwards on the glacier, reducing the friction at its base. The fluid pressure is compared to the ice overburden pressure, p i , given by ρgh. Under fast-flowing ice streams, these two pressures will be approximately equal, with an effective pressure (p i – p w ) of 30 kPa; i.e. all of

4332-453: Is thought to be a result of the relative lack of frequent windstorms like tropical cyclones . Along the western flanks of the mountains the increased orographic precipitation supports temperate rain forests in the Quinault, Queets, Hoh, and Bogachiel river valleys at low elevations. Protection by Olympic National Park, has allowed these rain forests to retain old growth trees, which supports

4446-952: The Andes , the Himalayas , the Rocky Mountains , the Caucasus , Scandinavian Mountains , and the Alps . Snezhnika glacier in Pirin Mountain, Bulgaria with a latitude of 41°46′09″ N is the southernmost glacial mass in Europe. Mainland Australia currently contains no glaciers, although a small glacier on Mount Kosciuszko was present in the last glacial period . In New Guinea, small, rapidly diminishing, glaciers are located on Puncak Jaya . Africa has glaciers on Mount Kilimanjaro in Tanzania, on Mount Kenya , and in

4560-754: The Duwamish Indians , while the first European to see them, the Spanish navigator Juan Pérez , named Mount Olympus "Santa Rosalia", in 1774. But the English captain John Meares , seeing them in 1788, thought he would honor the Greek explorer Juan de Fuca who claimed to have found the fabled Northwest passage nearby by naming the mountain after the mythical home of Greek gods which is " Mount Olympus " in Greece . Various names for

4674-636: The Faroe and Crozet Islands were completely glaciated. The permanent snow cover necessary for glacier formation is affected by factors such as the degree of slope on the land, amount of snowfall and the winds. Glaciers can be found in all latitudes except from 20° to 27° north and south of the equator where the presence of the descending limb of the Hadley circulation lowers precipitation so much that with high insolation snow lines reach above 6,500 m (21,330 ft). Between 19˚N and 19˚S, however, precipitation

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4788-750: The Himalayas , Andes , and a few high mountains in East Africa, Mexico, New Guinea and on Zard-Kuh in Iran. With more than 7,000 known glaciers, Pakistan has more glacial ice than any other country outside the polar regions. Glaciers cover about 10% of Earth's land surface. Continental glaciers cover nearly 13 million km (5 million sq mi) or about 98% of Antarctica 's 13.2 million km (5.1 million sq mi), with an average thickness of ice 2,100 m (7,000 ft). Greenland and Patagonia also have huge expanses of continental glaciers. The volume of glaciers, not including

4902-551: The Quaternary , Manchuria , lowland Siberia , and central and northern Alaska , though extraordinarily cold, had such light snowfall that glaciers could not form. In addition to the dry, unglaciated polar regions, some mountains and volcanoes in Bolivia, Chile and Argentina are high (4,500 to 6,900 m or 14,800 to 22,600 ft) and cold, but the relative lack of precipitation prevents snow from accumulating into glaciers. This

5016-521: The Rwenzori Mountains . Oceanic islands with glaciers include Iceland, several of the islands off the coast of Norway including Svalbard and Jan Mayen to the far north, New Zealand and the subantarctic islands of Marion , Heard , Grande Terre (Kerguelen) and Bouvet . During glacial periods of the Quaternary, Taiwan , Hawaii on Mauna Kea and Tenerife also had large alpine glaciers, while

5130-566: The Strait of Juan de Fuca ), Big Quilcene , Dosewallips , Duckabush , Hamma Hamma , and Skokomish (all flowing east into Hood Canal ). Principal summits: Other summits: A large portion of the range is contained within the Olympic National Park. Of this portion, 95% is part of the Daniel J. Evans Wilderness . The national park is surrounded on the south, east, and northwest sides by

5244-520: The 1957 hunting season, several times as many as expected; the excess was a logistical nightmare. One hunter was accidentally shot and died. A second hunter drowned in the Hoh River. A pack horse was shot. The Hoh River flooded, stranding hunters and washing away their camps. Forest Service and State Game personnel were overwhelmed with rescue efforts (lost, stranded, or injured hunters) and dispute resolution. Over 800 elk were killed, some left lying in

5358-448: The 1990s and 2000s. In a study using data from January 1993 through October 2005, more events were detected every year since 2002, and twice as many events were recorded in 2005 as there were in any other year. Ogives or Forbes bands are alternating wave crests and valleys that appear as dark and light bands of ice on glacier surfaces. They are linked to seasonal motion of glaciers; the width of one dark and one light band generally equals

5472-716: The Hoh, Queets, and Quinault rivers are typical U-shaped valleys carved by advancing alpine glaciers. Piles of talus and rockfall were created by retreating alpine glaciers. In the high mountains, the major rivers have their headwaters in alpine glacially carved cirques . During the Orting, followed by the Stuck, the Salmon Springs, and the Fraser glaciations, the vast continental Cordilleran Ice Sheet descended from Alaska south through British Columbia to

5586-443: The Olympic Mountains are the fisher ( Martes pennanti ) and the gray wolf ( Canis lupus ). The fisher was declared extirpated from Washington State when no fishers were detected during statewide carnivore surveys in the 1990s and 2000s. A reintroduction project was initiated in 2007, in partnership with Olympic National Park. The gray wolf was extirpated from Washington State in the early 20th century. The last wolf documented in

5700-663: The Olympic National Forest, with five wilderness areas, and on the southwest side by the Clearwater State Forest with one Natural Area Preserve (Washington Department of Natural Resources), and the Quinault Indian Reservation. State parks and wildlife areas occur in the lower elevations. Precipitation varies greatly throughout the range, from the wet western slopes to the semi-arid eastern ridges. Mount Olympus, nearly 8,000 feet (2,400 m) tall,

5814-426: The Olympic peninsula, along with the largest preserve of temperate old-growth forest, live in the national park. Spotted owls prey on flying squirrels and snowshoe hares, and are themselves preyed on by great horned owls Bubo virginianus . The density of the canopy of an old-growth forest gives the spotted owls some protection from the larger, less agile great horned owls. Rufous hummingbird ( Selasphorus rufus )

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5928-521: The Olympics as well as other parts of a limited range, include the Cope's giant salamander ( Dicamptodon copei ), and the Van Dyke's salamander ( Plethodon vandykei ,) both found primarily in the Olympics and other mountainous areas of western Washington; the tailed frog ( Ascaphus truei ), of Pacific Northwest mountain streams, and the mountain beaver ( Aplodontia rufa ) of the coastal Pacific Northwest. For

6042-602: The Olympics creates permanent snow and ice at lower elevations than is typical for other mountain ranges, cutting off the alpine vegetation zone. Most of the alpine vegetation is on the rain shadow side, in the northeastern Olympics, where there is less permanent snow and ice. Alpine vegetation is low herbaceous, typified by Phlox diffusa and species of Carex . Many of the Olympic Mountain's endemic plants occur here, such as Piper's bellflower ( Campanula piperi ) and Olympic violet ( Viola flettii ). Mammals extirpated from

6156-554: The Olympics was trapped in 1920. In the early 21st century, wolves are naturally migrating back into eastern and north-central Washington State, but there is no evidence of wolf migration into the Olympics and no plan to trans-locate wolves to the Olympics. The gray wolf is listed as endangered by the US Fish and Wildlife Service and the fisher is listed as state endangered by the Washington Fish and Wildlife Commission. Previous to

6270-505: The Olympics. The ice split into the Juan de Fuca and Puget ice lobes, as they encountered the resistant Olympic Mountains, carving out the current waterways and advanced as far south as present day Olympia. Ice flowed up the river valleys as far as 3,800 feet (1,200 m), carrying granitic glacial erratics with it. The mountains support a variety of different ecosystems, varying by elevation and relative east–west location, which influences

6384-577: The Pacific coast from the Russian River to Vancouver Island . Olympic and Vancouver Island elk are some of the last pure Roosevelt elk herds left; those in the Cascades have mixed with Rocky Mountain elk . Olympic National Park has the largest population of Roosevelt elk in the world. Some herds spend winter in lowland valleys, summer in high country, in subalpine meadows. Other herds live year-round in lowland forests and meadows. Elk prefer more humid areas,

6498-511: The Press and O'Neil expeditions were impressed by the quantity and tameness of the elk. Both expedition leaders prohibited shooting the elk and deer except when the expedition was in need of meat. The Olympic National Monument was formed to protect the elk after the herds were reduced to less than 2000 animals. The population rebounded, and in 1937 a hunting season for elk was opened in the Hoh River valley. An estimated 2,000–4,000 hunters came for

6612-401: The Sitka spruce, wet western hemlock, and mountain hemlock zones. Elk browsing is believed to be responsible for the open park-like structure of the Olympic rainforests; the elk graze on hemlock and shrubs, leaving the Sitka spruce to grow. Elk browsing also increases diversity of grasses and forbs. Elk exclosure experiments in rainforest valleys show more species of vegetation growing outside

6726-524: The State Game Commission. Mountain goats in the Olympics have been associated with damage to alpine vegetation and soil erosion. The goats have also been aggressive towards park visitors. In 1999, a mountain goat gored a hiker at the summit of Mount Ellinor in Olympic National Forest, and in 2010, a mountain goat fatally gored a hiker on the Klahane Ridge trail in Olympic National Park. In 2012,

6840-592: The Vancouver Island/North Cascades corner pushes Olympic rock upward and southwestward, resulting in strata that appear to be standing on edge and that intermix with strata of different mineral composition. All this occurred under water; the Olympics began to rise above the sea only 10–20 million years ago. The Olympics were shaped in the Pleistocene era by both alpine and continental glaciers advancing and retreating multiple times. The valleys of

6954-412: The advance of many alpine glaciers between 1950 and 1985, but since 1985 glacier retreat and mass loss has become larger and increasingly ubiquitous. Glaciers move downhill by the force of gravity and the internal deformation of ice. At the molecular level, ice consists of stacked layers of molecules with relatively weak bonds between layers. When the amount of strain (deformation) is proportional to

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7068-520: The air from the snow turns it into "glacial ice". This glacial ice will fill the cirque until it "overflows" through a geological weakness or vacancy, such as a gap between two mountains. When the mass of snow and ice reaches sufficient thickness, it begins to move by a combination of surface slope, gravity, and pressure. On steeper slopes, this can occur with as little as 15 m (49 ft) of snow-ice. In temperate glaciers, snow repeatedly freezes and thaws, changing into granular ice called firn . Under

7182-430: The amount of melting at surface of the glacier, the faster the ice will flow. Basal sliding is dominant in temperate or warm-based glaciers. The presence of basal meltwater depends on both bed temperature and other factors. For instance, the melting point of water decreases under pressure, meaning that water melts at a lower temperature under thicker glaciers. This acts as a "double whammy", because thicker glaciers have

7296-713: The annual movement of the glacier. Ogives are formed when ice from an icefall is severely broken up, increasing ablation surface area during summer. This creates a swale and space for snow accumulation in the winter, which in turn creates a ridge. Sometimes ogives consist only of undulations or color bands and are described as wave ogives or band ogives. Glaciers are present on every continent and in approximately fifty countries, excluding those (Australia, South Africa) that have glaciers only on distant subantarctic island territories. Extensive glaciers are found in Antarctica, Argentina, Chile, Canada, Pakistan, Alaska, Greenland and Iceland. Mountain glaciers are widespread, especially in

7410-493: The area is dominated by Douglas-fir . The reason for this is that Douglas-fir is an early seral species, and reproduces primarily after disturbances such as fire, logging, landslides, and windstorms. Western hemlock does not reproduce well on disturbed, exposed soil but germinates under the canopy of Douglas-fir, eventually overtaking the forest by shading out the Douglas-fir, which cannot reproduce in shade. In this zone, despite

7524-586: The bald eagle more so along the coast than in the mountains. Olympic rivers are dominated by Pacific salmonids , the Oncorhynchus . Chinook, coho, pink, rainbow and steelhead, and cutthroat all spawn in Olympic rivers. Chum and sockeye also live in coastal Olympic peninsula rivers but do not reach into the mountains. Bull trout ( Salvelinus confluentus ) and Dolly Varden trout ( S. malma ) also live in Olympic rivers. There are at least 16  endemic animal species. Near-endemics, those that occur in

7638-432: The bedrock has frequent fractures on the surface, glacial erosion rates tend to increase as plucking is the main erosive force on the surface; when the bedrock has wide gaps between sporadic fractures, however, abrasion tends to be the dominant erosive form and glacial erosion rates become slow. Glaciers in lower latitudes tend to be much more erosive than glaciers in higher latitudes, because they have more meltwater reaching

7752-445: The bedrock. By mapping the direction of the striations, researchers can determine the direction of the glacier's movement. Similar to striations are chatter marks , lines of crescent-shape depressions in the rock underlying a glacier. They are formed by abrasion when boulders in the glacier are repeatedly caught and released as they are dragged along the bedrock. The rate of glacier erosion varies. Six factors control erosion rate: When

7866-559: The created ice's density. The word glacier is a loanword from French and goes back, via Franco-Provençal , to the Vulgar Latin glaciārium , derived from the Late Latin glacia , and ultimately Latin glaciēs , meaning "ice". The processes and features caused by or related to glaciers are referred to as glacial. The process of glacier establishment, growth and flow is called glaciation . The corresponding area of study

7980-467: The deep profile of fjords , which can reach a kilometer in depth as ice is topographically steered into them. The extension of fjords inland increases the rate of ice sheet thinning since they are the principal conduits for draining ice sheets. It also makes the ice sheets more sensitive to changes in climate and the ocean. Although evidence in favor of glacial flow was known by the early 19th century, other theories of glacial motion were advanced, such as

8094-483: The deformation to become a plastic flow rather than elastic. Then, the glacier will begin to deform under its own weight and flow across the landscape. According to the Glen–Nye flow law , the relationship between stress and strain, and thus the rate of internal flow, can be modeled as follows: where: The lowest velocities are near the base of the glacier and along valley sides where friction acts against flow, causing

8208-582: The driest northeastern portion of the mountains. The Olympics are made up of obducted clastic wedge material and oceanic crust. They are primarily Eocene sandstones, turbidites , and basaltic oceanic crust. Unlike the Cascades , the Olympic Mountains are not volcanic, and contain no native granite. Millions of years ago, vents and fissures opened under the Pacific Ocean and lava flowed forth, creating huge underwater volcanic mountains and ranges called seamounts . The Farallon tectonic plate that formed

8322-487: The dry western hemlock, Douglas-fir, and subalpine fir zones. Similar to the elk, blacktail deer winter in lowlands, or along south-facing ridges, and summer in the high country meadows. Mountain beaver ( Aplodontia rufa ) is a large primitive rodent endemic to the Pacific Northwest. They are common in the Olympics, preferring wet scrubby thickets and second growth timber. Banana slug ( Ariolimax columbianus )

8436-418: The essentially correct explanation in the 1840s, although it was several decades before it was fully accepted. The top 50 m (160 ft) of a glacier are rigid because they are under low pressure . This upper section is known as the fracture zone and moves mostly as a single unit over the plastic-flowing lower section. When a glacier moves through irregular terrain, cracks called crevasses develop in

8550-457: The exclosures, where elk browse, than inside; while there are more brush and saplings inside exclosures, there are more grasses and forbs outside. Elk browsing improves forage for other herbivores like deer, voles and snowshoe hares. Elk prefer old growth forest and young alder groves over the large, even-aged plantations common on commercial timber land, although they will use small, recent clearcuts where they mimic natural forest openings. Both

8664-564: The extirpation of the gray wolf, coyotes ( Canis latrans ) occurred in the lowlands of the Olympic peninsula but not in the mountains. With the absence of wolves, coyotes have been moving up into the higher elevations of the mountains and may be responsible for population declines in the Olympic marmot . American black bear ( Ursus americanus ) are numerous in the Olympics. Olympic bears eat salmon, rodents, huckleberries, tree bark, insects, and deer or elk carcasses. Cougar ( Felis concolor )

8778-445: The forest. Proponents of a national park used the 1937 elk hunt as an argument in favor of permanent protection for Olympic's elk herds. Not all the elk herds are protected inside the national park: Some migrate in and out of the park, and others live entirely outside the park. All elk are subject to regulated hunting when outside the national park. Blacktail deer ( Odocoileus hemionus columbianus ) prefer drier areas than elk, such as

8892-455: The form of a domed cluster of steep-sided peaks surrounded by heavily forested foothills and incised by deep valleys. They are surrounded by water on three sides, separated from the Pacific by the 20 to 35 km (12 to 22 mi) wide coastal plain. The general form of the range is more or less circular, or somewhat horseshoe-shaped, and the drainage pattern is radial. Rivers radiate outwards to all sides. Clockwise from windward to leeward,

9006-475: The fracture zone. Crevasses form because of differences in glacier velocity. If two rigid sections of a glacier move at different speeds or directions, shear forces cause them to break apart, opening a crevasse. Crevasses are seldom more than 46 m (150 ft) deep but, in some cases, can be at least 300 m (1,000 ft) deep. Beneath this point, the plasticity of the ice prevents the formation of cracks. Intersecting crevasses can create isolated peaks in

9120-604: The future Olympics were being jammed into a corner created by the Vancouver Island and North Cascades microcontinents attached to the western edge of the North America plate. This is thought to be the origin of the curved shape of the Olympic Basaltic Horseshoe, an arc of submarine basalt running east along the Strait of Juan de Fuca, south along Hood Canal, and then west to Lake Quinault. Thrust-faulting northeast into

9234-453: The glacier to melt, creating a water source that is especially important for plants, animals and human uses when other sources may be scant. However, within high-altitude and Antarctic environments, the seasonal temperature difference is often not sufficient to release meltwater. Since glacial mass is affected by long-term climatic changes, e.g., precipitation , mean temperature , and cloud cover , glacial mass changes are considered among

9348-428: The glacier will be accommodated by motion in the sediments, or if it'll be able to slide. A soft bed, with high porosity and low pore fluid pressure, allows the glacier to move by sediment sliding: the base of the glacier may even remain frozen to the bed, where the underlying sediment slips underneath it like a tube of toothpaste. A hard bed cannot deform in this way; therefore the only way for hard-based glaciers to move

9462-504: The glacier's surface area, more if the glacier calves icebergs. Ice in the accumulation zone is deep enough to exert a downward force that erodes underlying rock. After a glacier melts, it often leaves behind a bowl- or amphitheater-shaped depression that ranges in size from large basins like the Great Lakes to smaller mountain depressions known as cirques . The accumulation zone can be subdivided based on its melt conditions. The health of

9576-466: The high annual precipitation, drought stress in summer is sufficiently severe to limit growth of many species, such as Sitka spruce. Hardwoods such as bigleaf maple, willows, and red alder are limited to disturbed sites and riparian areas. red-cedar grows in the wettest sites. A very small area of the northeastern rain shadow contains the limited Douglas-fir zone, where it is too dry for western hemlock. Moving up in elevation and moisture availability

9690-403: The high country to hunt elk, gather huckleberries and beargrass, and perform spirit quests. Trails across the mountains allowed members of the various tribes to visit and trade with each other. The cross-Olympic expeditions of the 1890s found tree blazes that they took to mark Indian trails. Archeological evidence shows that the Olympic Mountains were inhabited by Paleolithic hunters after

9804-614: The ice at the bottom of the glacier move more slowly than ice at the top. In alpine glaciers, friction is also generated at the valley's sidewalls, which slows the edges relative to the center. Mean glacial speed varies greatly but is typically around 1 m (3 ft) per day. There may be no motion in stagnant areas; for example, in parts of Alaska, trees can establish themselves on surface sediment deposits. In other cases, glaciers can move as fast as 20–30 m (70–100 ft) per day, such as in Greenland's Jakobshavn Isbræ . Glacial speed

9918-420: The ice sheets of Antarctica and Greenland, has been estimated at 170,000 km . Glacial ice is the largest reservoir of fresh water on Earth, holding with ice sheets about 69 percent of the world's freshwater. Many glaciers from temperate , alpine and seasonal polar climates store water as ice during the colder seasons and release it later in the form of meltwater as warmer summer temperatures cause

10032-544: The ice to act as a lever that loosens the rock by lifting it. Thus, sediments of all sizes become part of the glacier's load. If a retreating glacier gains enough debris, it may become a rock glacier , like the Timpanogos Glacier in Utah. Abrasion occurs when the ice and its load of rock fragments slide over bedrock and function as sandpaper, smoothing and polishing the bedrock below. The pulverized rock this process produces

10146-488: The ice, called seracs . Crevasses can form in several different ways. Transverse crevasses are transverse to flow and form where steeper slopes cause a glacier to accelerate. Longitudinal crevasses form semi-parallel to flow where a glacier expands laterally. Marginal crevasses form near the edge of the glacier, caused by the reduction in speed caused by friction of the valley walls. Marginal crevasses are largely transverse to flow. Moving glacier ice can sometimes separate from

10260-411: The idea that meltwater, refreezing inside glaciers, caused the glacier to dilate and extend its length. As it became clear that glaciers behaved to some degree as if the ice were a viscous fluid, it was argued that "regelation", or the melting and refreezing of ice at a temperature lowered by the pressure on the ice inside the glacier, was what allowed the ice to deform and flow. James Forbes came up with

10374-418: The increased pressure can facilitate melting. Most importantly, τ D is increased. These factors will combine to accelerate the glacier. As friction increases with the square of velocity, faster motion will greatly increase frictional heating, with ensuing melting – which causes a positive feedback, increasing ice speed to a faster flow rate still: west Antarctic glaciers are known to reach velocities of up to

10488-423: The infrared OH stretching mode of the water molecule. (Liquid water appears blue for the same reason. The blue of glacier ice is sometimes misattributed to Rayleigh scattering of bubbles in the ice.) A glacier originates at a location called its glacier head and terminates at its glacier foot, snout, or terminus . Glaciers are broken into zones based on surface snowpack and melt conditions. The ablation zone

10602-422: The local climate, primarily precipitation. Olympic forests are coniferous forests, unique among mesic temperate forests in their almost complete dominance by conifers rather than by hardwoods. The hardwood:conifer timber volume ratio is 1:1,000 in the maritime Pacific Northwest. Another unique feature of Olympic forests is the size and longevity of the dominant tree species. Every coniferous genus represented here

10716-525: The low herbaceous meadows of pumice, talus and scree slopes and other rocky areas. American saw-wort is common in both mountain meadows and lower subalpine parklands in the Olympics. Above timberline is the Alpine zone, not a forest zone since no trees can grow this high. The alpine zone in the Olympics is much more limited in size than in other temperate mountain ranges, from 1,800 metres (5,900 ft) to 2,250 metres (7,380 ft). The high precipitation of

10830-774: The major watersheds are: Satsop , Wynoochee , Humptulips , Quinault , Queets , Hoh , Bogachiel , Sol Duc (all flowing west into the Pacific Ocean; with the Satsop, Wynoochee by way of the Chehalis River , the Humptulips by way of Grays Harbor at the mouth of the Chehalis River, and the Bogachiel and Sol Duc forming the Quillayute River within 5 miles (8.0 km) of tidewater), Lyre , Elwha , Dungeness (all flowing north into

10944-679: The most deformation. Velocity increases inward toward the center line and upward, as the amount of deformation decreases. The highest flow velocities are found at the surface, representing the sum of the velocities of all the layers below. Because ice can flow faster where it is thicker, the rate of glacier-induced erosion is directly proportional to the thickness of overlying ice. Consequently, pre-glacial low hollows will be deepened and pre-existing topography will be amplified by glacial action, while nunataks , which protrude above ice sheets, barely erode at all – erosion has been estimated as 5 m per 1.2 million years. This explains, for example,

11058-445: The most sensitive indicators of climate change and are a major source of variations in sea level . A large piece of compressed ice, or a glacier, appears blue , as large quantities of water appear blue , because water molecules absorb other colors more efficiently than blue. The other reason for the blue color of glaciers is the lack of air bubbles. Air bubbles, which give a white color to ice, are squeezed out by pressure increasing

11172-701: The mountains were used based on the name Mount Olympus, including the Olympic Range, the Olympian Mountains, and the Olympus Range. Alternate proposals never caught on, and in 1864 the Seattle Weekly Gazette persuaded the government to make the present-day name official, although other names continued to be used. Glacier A glacier ( US : / ˈ ɡ l eɪ ʃ ər / ; UK : / ˈ ɡ l æ s i ər , ˈ ɡ l eɪ s i ər / )

11286-468: The northeast of the mountains are located in a rain shadow cast by the mountain themselves, and receive as little as 16 in (410 mm) of precipitation around the city of Sequim. Annual precipitation increases to about 30 in (760 mm) on the edges of the rain shadow around Port Townsend, the San Juan Islands, and the city of Everett across Puget Sound. 80% of precipitation falls during

11400-673: The original inhabitants of the Olympic Peninsula, the highest peaks of the mountains were the only refuges during the Great Floods at the beginning of time. For the Elwha Klallam people, that peak was Mount Carrie; for the Skokomish, it was a peak west of Mount Ellinor. The Thunderbird figure of the Hoh tribe lived on Mount Olympus, in a den under Blue Glacier. People in the Skokomish, Quinault, and Elwha watersheds regularly traveled into

11514-721: The pooling of meltwater at the base of the glacier  — perhaps delivered from a supraglacial lake  — or the simple accumulation of mass beyond a critical "tipping point". Temporary rates up to 90 m (300 ft) per day have occurred when increased temperature or overlying pressure caused bottom ice to melt and water to accumulate beneath a glacier. In glaciated areas where the glacier moves faster than one km per year, glacial earthquakes occur. These are large scale earthquakes that have seismic magnitudes as high as 6.1. The number of glacial earthquakes in Greenland peaks every year in July, August, and September and increased rapidly in

11628-410: The pressure of the layers of ice and snow above it, this granular ice fuses into denser firn. Over a period of years, layers of firn undergo further compaction and become glacial ice. Glacier ice is slightly more dense than ice formed from frozen water because glacier ice contains fewer trapped air bubbles. Glacial ice has a distinctive blue tint because it absorbs some red light due to an overtone of

11742-604: The retreat of the Cordilleran Ice Sheet . Stone tools in the Deer Park area date to 7600 years ago, prior to the volcanic eruption of Mount Mazama . Similar tools have been found near Lake Cushman and throughout the Olympic subalpine meadows and ridges, as well as in coastal areas. In addition, a fragment of a woven basket found in the Olympic subalpine of Obstruction Point was radiocarbon dated to nearly 3000 years ago. The mountains were originally called " Sun-a-do " by

11856-558: The sea, often with an ice tongue , like Mertz Glacier . Tidewater glaciers are glaciers that terminate in the sea, including most glaciers flowing from Greenland, Antarctica, Baffin , Devon , and Ellesmere Islands in Canada, Southeast Alaska , and the Northern and Southern Patagonian Ice Fields . As the ice reaches the sea, pieces break off or calve, forming icebergs . Most tidewater glaciers calve above sea level, which often results in

11970-441: The slide alder chutes and the silver fir forest. The next higher forest zone is the mountain hemlock zone, the highest forest zone in the Olympic mountains. In this zone most precipitation falls as snow and the snow-free growing season is very short. In the drier rainshadow side of the mountains, mountain hemlock is largely replaced by subalpine fir . At the higher elevations of the mountain hemlock/subalpine fir zone, tree cover

12084-409: The stagnant ice above, forming a bergschrund . Bergschrunds resemble crevasses but are singular features at a glacier's margins. Crevasses make travel over glaciers hazardous, especially when they are hidden by fragile snow bridges . Below the equilibrium line, glacial meltwater is concentrated in stream channels. Meltwater can pool in proglacial lakes on top of a glacier or descend into the depths of

12198-423: The stress being applied, ice will act as an elastic solid. Ice needs to be at least 30 m (98 ft) thick to even start flowing, but once its thickness exceeds about 50 m (160 ft) (160 ft), stress on the layer above will exceeds the inter-layer binding strength, and then it'll move faster than the layer below. This means that small amounts of stress can result in a large amount of strain, causing

12312-486: The subalpine zone is dominated by subalpine fir. It can occur with other trees, including mountain hemlock, silver fir, and yellow-cedar, but what characterizes these zones is the dominance of subalpine fir. These forests occur on the eastern ridges from 1,300 to 1,800 metres (4,300 to 5,900 ft). In the Olympics, the treeline is between 5,000 feet (1,500 m) and 6,000 feet (1,800 m) but can be as low as under 4,000 feet (1,200 m) in some places. Treeline

12426-438: The surface snowpack may experience seasonal melting. A subpolar glacier includes both temperate and polar ice, depending on the depth beneath the surface and position along the length of the glacier. In a similar way, the thermal regime of a glacier is often described by its basal temperature. A cold-based glacier is below freezing at the ice-ground interface and is thus frozen to the underlying substrate. A warm-based glacier

12540-577: The trail to Mount Ellinor was closed in summer due to aggressive goats, re-opening in the fall. An airlifting effort by the National Park Service started in September 2018 in an attempt to relocate the goats to the Cascades region. NPS hopes to relocate several hundred goats before starting a lethal removal option. The park service hopes to reduce the goat population to 0-50 animals by 2028. Roosevelt elk Cervus canadensis roosevelti range along

12654-417: The weight of the ice is supported by the underlying water, and the glacier is afloat. Glaciers may also move by basal sliding , where the base of the glacier is lubricated by the presence of liquid water, reducing basal shear stress and allowing the glacier to slide over the terrain on which it sits. Meltwater may be produced by pressure-induced melting, friction or geothermal heat . The more variable

12768-404: The western coastal plain and not in mountainous areas, although it can be found as high as 1,900 feet (580 m). The lower elevations of the Olympic mountains, from roughly 480 feet (150 m) up to 1,800 feet (550 m) – 3,700 feet (1,100 m), feature the western hemlock zone, so-called because in most of the zone, the climax tree species would be western hemlock, even though much of

12882-400: The winter months. On the coastal plain, the winter temperature stays between −2 and 7 °C (28 and 45 °F). During the summer it warms up to between 10 and 24 °C (50 and 75 °F), with occasional hot spell days reaching to the upper 80s to low 90s °F (30-35 °C). The large number of snowfields and glaciers , reaching down to 1,500 m (5,000 ft) above sea level, are

12996-401: The winter precipitation by continuing to photosynthesize through fall, winter and early spring, when deciduous trees are not able to photosynthesize. No deciduous conifers occur in the Olympics; larch trees occur in the much-drier eastern Cascades, but not in the Olympics or western Cascades. There is only one species of evergreen hardwood, the madrone . The great size and age of conifers here

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