106-514: Itasca State Park ( / aɪ ˈ t æ s k ə / ) is a state park of Minnesota , United States , and contains the headwaters of the Mississippi River . The park spans 32,690 acres (132.3 km) of northern Minnesota, and is located about 21 miles (34 km) north of Park Rapids, Minnesota and 25 miles (40 km) from Bagley, Minnesota . The park is part of Minnesota's Pine Moraines and Outwash Plains Ecological Subsection and
212-424: 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
318-526: A land lease from the U.S. government , while Mackinac National Park was handed down to become the first of the Michigan state parks . As with national parks, facilities at state parks are often leased to concessionaires to operate. Breaks Interstate Park is operated under an interstate compact by Virginia state parks , although it is also one of the Kentucky state parks , straddling both sides of
424-669: A combination of aspen and birch trees, with aspen being the most dominant species of tree in the park today. The four principal forest communities in this locale remain to be aspen–birch, red pine, white pine, and northern hardwoods. The park is home to fourteen plants placed on the state endangered species list; these consist of ram's–head lady's slipper (Cypripedium arietinum) , olivaceous spike–rush ( Eleocharis olivacea ) , bog adder's–mouth ( Malaxis paludosa ) , slender naiad ( Najas gracillma ) , and sheathed pondweed ( Potamogeton vaginatus ) . Three terrestrial biomes, coniferous forest , deciduous forest, and prairie all intersect in
530-589: A few exceptions such as Anza-Borrego Desert State Park in California, and Wood-Tikchik State Park in Alaska, the largest state park in the United States . In addition to preserving natural landscapes and providing recreational opportunities, many state parks also serve as important educational resources . They often offer guided tours, interpretive programs, and exhibits that help visitors learn about
636-522: 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
742-601: 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
848-411: 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
954-408: 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
1060-404: 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
1166-460: 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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#17327653322351272-699: A restaurant) for lodging at some parks. These typically use "Resort" in the name, such as "_____ Resort State Park" in West Virginia state parks and "_____ State Resort Park" in neighboring Kentucky state parks , which has 17 such resort parks, the most of any state. Other states use the Resort name inconsistently (like DeGray Lake Resort State Park , the only one out of three resorts in Arkansas state parks ), or have only one such park ( South Carolina state parks ' Hickory Knob State Resort Park ), or do not use
1378-488: 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
1484-410: 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
1590-464: A two–story Rustic Style lobby. The Clubhouse contains a very large fireplace, couches, and a very great staircase. Over the years, the Clubhouse encountered few problems in the maintenance department other than minor deterioration in the lower logs, which were replaced in 1984. Today, guests may stay in the ten rooms. The Old Timer's Cabin is also found on the shores of Lake Itasca, located north of
1696-456: 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
1802-407: 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,
1908-537: Is also Minnesota's state tree . Some of the red pine in Itasca are over 200 years old. The Itasca terrain is sometimes referred to as "knob and kettle." The knobs are mounds of debris deposited directly by the ice near the edge of glaciers or by melt–water streams flowing on or under the glacier's surface. The kettles are depressions, usually filled with water, formed by dormant ice masses buried or partially buried under glacial debris that later melted. The retreat of
2014-411: 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
2120-406: 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
2226-434: 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
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#17327653322352332-416: 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
2438-603: Is contained within Clearwater , Hubbard , and Becker counties. Itasca State Park was established by the Minnesota Legislature on April 20, 1891, making it the first of Minnesota's state parks and second oldest in the United States, behind Niagara Falls State Park . Henry Schoolcraft determined Lake Itasca as the river's source in 1832. It was named as a National Natural Landmark in 1965, and
2544-647: 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
2650-854: Is only known to live in Nicollet Creek in the park. Under the name of Itasca Natural Area , the area was designated a National Natural Landmark by the National Park Service under the Historic Sites Act . It received this designation in November 1965 from the United States Secretary of the Interior , giving it recognition as an outstanding example of the nation's natural history. The designation describes its significance: The area contains some of
2756-897: 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
2862-413: 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
2968-402: 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
3074-552: 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
3180-993: 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
3286-758: The Civilian Conservation Corps and Works Progress Administration . 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 / ) 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
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3392-644: 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
3498-760: 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
3604-562: 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
3710-535: 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
3816-544: The University of Minnesota to conduct an extensive excavation of the area in 1964 and 1965. Excavation of the area revealed a large of amount of bones from an extinct species of Bison hence the name of the site. Human tools, such as knives, spears and scrapers were discovered in the vicinity. The Itasca State Park Site was discovered and excavated by Jacob Brower in the late 19th century. The site consists of ten burial mounds, dating back approximately 800 years, along
3922-435: The ice fishermen , who gather on Lake Itasca. Snowmobilers can travel hundreds of miles of groomed snowmobile trails, while the skiers use 30 miles (48 km) of cross country skiing trails (both novice and skilled level) that are maintained regularly. Scattered around the boundaries of Itasca State Park stand a variety of historical and tourist attractions. Constructed over a 37-year period from 1905 to 1942, development
4028-494: The "Nature of Life" orientation program which is held by the lake, allowing the study of a diverse, undisturbed environment from the organismal level to that of an entire ecosystem. Lake Itasca, the official source of the Mississippi River and a scenic area of northern Minnesota, has remained relatively unchanged from its natural state. Most of the area has a heavy growth of timber that includes virgin red pine , which
4134-448: 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
4240-674: The Archaic and Woodland periods. The Itasca Bison Kill Site is the oldest archaeological site within Itasca State Park. The site dates back to the Early Eastern Archaic period. The discovery took place in 1937 during the construction of the Wilderness Drive. It is located near the southwestern shore of Lake Itasca by Nicollet Creek. An initial finding of the remains of human made artifacts prompted
4346-590: The Arctic air with heavy snowfall and wind can create severe blizzard conditions in the area. In the summer, the Pacific and tropical winds from the Gulf create warm to hot temperatures, with the highs during July averaging 78.4 °F (25.8 °C). However a clash of cool, dry polar air from Canada and the moisture from the southern tropical Gulf air can lead to showers and thunderstorms. The average annual rainfall in
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4452-588: The Clubhouse. This was the first CCC–constructed building to appear in the park. The CCC originally referred to the Old Timer's Cabin as the "Honeymooner's Cabin" because of its small size and relative isolation . Forest Inn is one of the largest creations by the CCC in the state park system, standing 144 by 50 feet (44 by 15 m). It took a crew of 200 CCC members to produce the finished product, complete with both split stone and log components. The stone used in
4558-571: The Heartland Trail, horseback riding , and hiking. A 9.6-mile (15.4 km) section of the North Country National Scenic Trail passes through the park's southern tier and includes three backcountry campsites. Numerous historical sites are available to view. The headwaters of the Mississippi River are one of the most visited sites featured at the park. Tourists can visit the new Mary Gibbs Visitor Center and
4664-482: The Itasca area is 27 inches (69 cm). It has a relatively short growing season, with the first frost usually occurring in late September to early October and the first frost-free days not occurring until mid-May or early June. Itasca State Park's recreational activities cover all four seasons of the year. Within the restored log building headquarters is a 31-bed youth hostel operated by Hostelling International USA, open to travelers of all ages. Spring reels in
4770-531: The Itasca region and allow habitat for numerous vegetation and animals. Itasca is home to over 200 bird species encompassing: bald eagles , loons , grebes , cormorants , herons , ducks , owls , hummingbirds , woodpeckers , chickadees , nuthatches , kinglets , vireos , tanagers , finches , and warblers . Residing among the many trails in the park are over 60 types of mammals including beaver , porcupine , black bear , and timber wolves . The white-tailed deer overpopulation has caused problems within
4876-547: The Mississippi headwaters. The area is currently one of the few places in state that has preserved these ancient pines from destruction. These pine forests were the main concern of Brower when he pushed to preserve the area as a state park. Logging operations in the late 19th and early 20th centuries depleted the large pine forests found in the park. Logging ended around 1920. Pine restoration has been attempted dating back to 1902, but with limited success. Fire suppression in
4982-424: The Mississippi's headwaters. Brower saw this region being quickly transformed by logging , and was determined to protect some of the pine forests for future generations. It was Brower's tireless efforts to save the remaining pine forest surrounding Lake Itasca that led the state legislature to establish Itasca as a Minnesota State Park on April 20, 1891, by a margin of only one vote. Through his conservation work and
5088-412: 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
5194-520: 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
5300-430: 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
5406-713: 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
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#17327653322355512-509: The area and during the summer month a tropical air stream flows north from the Gulf of Mexico . These various air masses have a strong effect on the climate of the area around Itasca State Park. The winter climate produces extremely cold temperatures, with an average minimum temperature for Itasca being −4 °F (−20 °C). This cold weather is accompanied with snowfall amounts averaging around 54.6 inches (139 cm) annually. A combination of
5618-445: The area has eliminated wildfires in the park since the 1920s. Fire is necessary to the regeneration of white, red, and jack pines in the area because it opens the forest floor and canopy for new trees to grow. An overpopulation of white-tailed deer also stunt the regeneration efforts of these pines, as deer browse young pine seedling and prevent them from maturing into trees. A combination of jack pine and northern pin oak dominated
5724-490: The area. Itasca's rustic style design is the largest collection of log–constructed buildings in the state park system. It provides a uniform appearance to the park, setting it apart from all others. Douglas Lodge , built in 1905, is the oldest surviving building and the first to be constructed in the Rustic Style. This structure is located along the south shore of Lake Itasca and was built using peeled logs harvested from
5830-432: 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
5936-445: 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
6042-607: The bridge constructed of logs. In 1903 a 24-year-old park commissioner named Mary Gibbs played a significant role in saving the tall pine forests and shoreline of the Mississippi River Headwaters by resisting efforts to log the area. In honor of her efforts, the Mary Gibbs Visitor Center, which encloses a restaurant, gift shop, various displays and exhibits of the park's features, and an outdoor plaza now exists. Visitors can walk across
6148-504: The continuing efforts of others throughout the decades, the grounds of Itasca had been maintained. Established in 1909, Itasca Biological Station and Labs (IBSL) is one of the oldest and largest continuously operated inland field training centers in the United States. This site serves as a research facility and a site for summer-session undergraduate field biology courses for the University of Minnesota College of Biological Sciences . Each year new College of Biological Sciences students attend
6254-675: The country's state parks. The NASPD further counts over 43,000 miles (69,000 km) of trail, 217,367 campsites, and 8,277 cabins and lodges across U.S. state parks. The largest state park system in the United States is Alaska State Parks , with over 100 sites encompassing 3.3 million acres. Many states include designations beyond "state park" in their state parks systems. Other designations might be state recreation areas , state beaches, and state nature reserves . Some state park systems include long-distance trails and historic sites . To encourage tourism in rural areas, several states have simple lodges, inns, hotels, or motels (usually with
6360-571: 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
6466-467: 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
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#17327653322356572-483: 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
6678-478: The designation at all (such as the lodges of Georgia state parks ). The term "lodge" may also refer to a hiking lodge , essentially a large cabin for hikers rather than a large facility with private rooms and a restaurant. Other lodging may include yurts and tipis . Not all parks owned by a state are necessarily part of its state-park system, such as Stone Mountain Park near Atlanta. Some Texas state parks are
6784-418: 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
6890-480: The exhibits at the Jacob V. Brower Visitor Center. The park also offers a 100-foot (30 m) climb up the historic Aiton Heights Fire Tower. Fall unveils the beautiful array of colors amidst the variety of trees throughout the park. This is another recommended season to bike, hike, or even take a leisurely walk through the designated trails. The park offers 33 miles (53 km) worth of hiking trails. Winter lures in
6996-402: The finest remaining stands of virgin red pine, spruce-balsam fir, and maple-basswood-aspen forest, supporting 141 bird and 53 mammal species, including bald eagles. Itasca State Park lies in northern Minnesota; a location that can be affected by three major air masses . An Arctic air stream extends south from Canada during the winter months; Pacific air that follows strong west winds move over
7102-579: The fishermen for the May fishing openers of walleye , northern pike , bass , and panfish . The park is in full bloom including a vast array of wildflowers . Birding is also a popular spring activity as the varying species return from migration. Lake Itasca is a popular location for summer activities in Minnesota, with 496,651 visitors in 2006. Fishing, canoeing, boating, and kayaking equipment are always accessible. On land recreation consists of biking via
7208-475: 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
7314-453: 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
7420-428: 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
7526-510: 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
7632-875: The government of each U.S. state , some of the Mexican states , and in Brazil . The term is also used in the Australian states of Victoria and New South Wales . The equivalent term used in Canada, Argentina, South Africa, and Belgium, is provincial park . Similar systems of local government maintained parks exist in other countries, but the terminology varies. State parks are thus similar to national parks , but under state rather than federal administration. Similarly, local government entities below state level may maintain parks, e.g., regional parks or county parks . In general, state parks are smaller than national parks, with
7738-463: The ice around 10,000 years ago left behind 157 lakes of varying size that cover 3,000 acres (12 km) of Itasca State Park. The glaciers deposited a moraine , a combination of silt , clay , sand , and gravel that covers the landscape to a depth of around 680 feet (210 m). The park also integrates 27,500 acres (111 km) of upland and 1,500 acres (6.1 km) of swamp . The Itasca area's old-growth pine forests are almost as famous as
7844-619: 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
7950-420: 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
8056-556: 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
8162-488: 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
8268-411: 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
8374-418: 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
8480-423: 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
8586-574: The late 19th century. Significant portions of this site have been converted into trails, parking lots and visitor service facilities. Archaeological remains have also been discovered at the Headwater's West Terrace Site along the west bank of the Mississippi near Lake Itasca, the Bear Paw Campground Site which lies adjacent to Lake Itasca, as well as Pioneer Cemetery which is located on the eastern shore of Lake Itasca and contains
8692-493: The local flora , fauna , geology , and cultural history of the area. These programs are designed not only to enhance the visitor experience but also to promote conservation awareness and encourage responsible enjoyment of natural resources. There are 6,792 state park units in the United States, according to the National Association of State Park Directors (NASPD). There are some 813 million annual visits to
8798-679: 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,
8904-445: 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
9010-500: The northeastern shore of Lake Itasca. An effort was made in the late 1980s to rebury American Indian remains that had been removed. This act was in collaboration with a statewide effort to rebury the several thousand remains that had been excavated. Several other major sites exist in Itasca, including the Headwaters Site , which is located along the northeast shore of Lake Itasca, and a village site discovered by Jacob Brower in
9116-409: The park before European settlement. Among the numerous varieties of trees Itasca accommodates are quaking aspen , bigtooth aspen , paper birch , red pine , white pine , as well as a mix of northern hardwoods. Current vegetation of the park now include: eastern white pine, red pine, aspen–birch, mixed hardwoods, jack pine barrens , and conifer bog. Logged areas of white and red pine are now home to
9222-552: The park gives visitors historical insight about this period. A few thousand years later, a group of people of the Woodland Period arrived at Lake Itasca. They lived in larger, more permanent settlements and made a variety of stone, wood, and bone tools. Burial mounds from this era can be seen today at the Itasca Indian Cemetery. In 1832 Anishinaabe guide Ozawindib led explorer Henry Schoolcraft to
9328-527: The park. According to 1998 statistics it was estimated that the density of deer is around 15 to 17 per square mile compared with the 4–10 per square mile in similar areas in Wisconsin . The cause of the deer boom was the addition of man-made open spaces and a deer protection zone put in place from the early 20th century until the 1940s. Annual deer hunts have been held since 1940 in an effort to curb white tail deer population. The caddisfly Chilostigma itascae
9434-725: 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
9540-410: 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
9646-418: The remains of early European pioneers. State park State parks are parks or other protected areas managed at the sub-national level within those nations which use "state" as a political subdivision. State parks are typically established by a state to preserve a location on account of its natural beauty, historic interest, or recreational potential. There are state parks under the administration of
9752-523: The rocks connecting the sides of the Mississippi. There is also a bridge, for those who don't want to get wet. Itasca State Park currently contains more than 30 known archaeological and cemetery sites . The study of archaeological remains in the Itasca area was started by Jacob V. Brower in the late 19th century. Survey work on archaeological remains place human activity in the Itasca area as early as 8,000 years ago. Human activity spans over several historical periods , from Early Eastern Archaic, through
9858-514: 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
9964-473: The significance of this encounter. Douglas Lodge has provided tourist facilities since 1911 and remains functional today after undergoing renovations in the years following its grand opening. The Lodge is used as a hotel for guests to stay in, and the main lobby for the "Douglas Lodge Cabins" around it. There is also a restaurant famous for wild rice soup. The Clubhouse , assembled in 1911, overlooks Lake Itasca. The interior contains ten dormitories placed around
10070-452: The source of the Mississippi River at Lake Itasca. It was on this journey that Schoolcraft, with the help of an educated missionary companion, created the name Itasca from the Latin words for "truth" and "head" ( veritas caput ). In the late 19th century, Jacob V. Brower , historian , anthropologist and land surveyor , came to the park region to settle the dispute of the actual location of
10176-409: 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
10282-474: The state line. Other multi-state parks are legally two separate parks with the same name and more informal cooperation between them. The title of oldest state park in the United States is claimed by Niagara Falls State Park in New York , established in 1885. Several public parks previously or currently maintained at the state level pre-date it. Indian Springs State Park has been operated continuously by
10388-454: The state of Georgia as a public park since 1825, although it did not gain the title "State Park" until 1931. In 1864 Yosemite Valley and Mariposa Grove were ceded by the federal government to California until Yosemite National Park was proclaimed in 1890. In 1878 Wisconsin set aside a vast swath of its northern forests as "The State Park" but, needing money, sold most of it to lumber companies within 20 years. Mackinac National Park
10494-423: 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
10600-438: 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
10706-456: The surrounding forests. Funded by State legislature in 1903, it became the first building to house the park's visitors. Originally, it was called "Itasca Park Lodge" or "State House", but was later named after Minnesota Attorney General Wallace B. Douglas , a prominent figure in the battle to save the timber in Itasca State Park at the start of the 20th century. At the time, very few governments were setting aside land for conservation, which shows
10812-450: The walkways were scrap pieces from the quarries and stone works of the St. Cloud area and the logs used on the cabin came from the pine and balsam fir within the park vicinity. The headwaters of the Mississippi River are clearly defined by a 44-foot-long (13 m) long outlet dam at the north end of Lake Itasca. This setup allows tourists to wade in shallow water or cross over it by way of
10918-417: 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
11024-480: Was added to the National Register of Historic Places in 1973. About 500,000 people visit Itasca State Park annually. Approximately 7–8,000 years ago, Native American hunters pursued wild animals for food in the Itasca State Park region. These early people ambushed bison , deer , and moose at watering sites and killed them with stone–tipped spears. The bison kill site along Wilderness Drive in
11130-473: Was established in 1875 as the second U.S. national park before being converted to a state park in 1895. The first state park with the designation of "state park" was Itasca State Park in Minnesota , established in 1891. Many state park systems date to the 1930s, when around 800 state parks (and several national ones) across the country were developed with assistance from federal job-creation programs like
11236-494: Was undertaken by two Civilian Conservation Corps (CCC) camps as well as two Works Progress Administration (WPA) camps. Architects for this later development were from the Minnesota Central Design Office of the National Park Service with Edward W. Barber and V.C. Martin serving as principal architects for the park buildings. Log construction was generally used because timber was easily available in
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