A river mouth is the part of a river where the river debouches into another river, a lake, a reservoir, a sea, or an ocean. The water from a river can enter the receiving body in a variety of different ways; the motion of a river is influenced by the relative density of the river compared to the receiving water, the rotation of the earth, any ambient motion in the receiving water, such as tides or seiches. If the river water has a higher density than the surface of the receiving water, the river water will plunge below the surface; the river water will either form an underflow or an interflow within the lake. However, if the river water is lighter than the receiving water, as is the case when fresh river water flows into the sea, the river water will float along the surface of the receiving water as an overflow. Alongside these advective transports, inflowing water will diffuse. At the mouth of a river, the change in flow condition can cause the river to drop any sediment it is carrying; this sediment deposition can generate a variety of landforms, such as deltas, sand bars and tie channels.
Many places in the United Kingdom take their names from their positions at the mouths of rivers, such as Plymouth and Great Yarmouth. Confluence River delta Estuary Liman
An ecoregion is an ecologically and geographically defined area, smaller than a bioregion, which in turn is smaller than an ecozone. All three of these are either greater than an ecosystem. Ecoregions cover large areas of land or water, contain characteristic, geographically distinct assemblages of natural communities and species; the biodiversity of flora and ecosystems that characterise an ecoregion tends to be distinct from that of other ecoregions. In theory, biodiversity or conservation ecoregions are large areas of land or water where the probability of encountering different species and communities at any given point remains constant, within an acceptable range of variation. Three caveats are appropriate for all bio-geographic mapping approaches. Firstly, no single bio-geographic framework is optimal for all taxa. Ecoregions reflect the best compromise for as many taxa as possible. Secondly, ecoregion boundaries form abrupt edges. Thirdly, most ecoregions contain habitats. Biogeographic provinces may originate due to various barriers.
Some physical, some climatic and some ocean chemical related. The history of the term is somewhat vague, it had been used in many contexts: forest classifications, biome classifications, biogeographic classifications, etc; the concept of ecoregion of Bailey gives more importance to ecological criteria, while the WWF concept gives more importance to biogeography, that is, distribution of distinct biotas. An ecoregion is a "recurring pattern of ecosystems associated with characteristic combinations of soil and landform that characterise that region". Omernik elaborates on this by defining ecoregions as: "areas within which there is spatial coincidence in characteristics of geographical phenomena associated with differences in the quality and integrity of ecosystems". "Characteristics of geographical phenomena" may include geology, vegetation, hydrology and aquatic fauna, soils, may or may not include the impacts of human activity. There is significant, but not absolute, spatial correlation among these characteristics, making the delineation of ecoregions an imperfect science.
Another complication is that environmental conditions across an ecoregion boundary may change gradually, e.g. the prairie-forest transition in the midwestern United States, making it difficult to identify an exact dividing boundary. Such transition zones are called ecotones. Ecoregions can be categorized using an algorithmic approach or a holistic, "weight-of-evidence" approach where the importance of various factors may vary. An example of the algorithmic approach is Robert Bailey's work for the U. S. Forest Service, which uses a hierarchical classification that first divides land areas into large regions based on climatic factors, subdivides these regions, based first on dominant potential vegetation, by geomorphology and soil characteristics; the weight-of-evidence approach is exemplified by James Omernik's work for the United States Environmental Protection Agency, subsequently adopted for North America by the Commission for Environmental Cooperation. The intended purpose of ecoregion delineation may affect the method used.
For example, the WWF ecoregions were developed to aid in biodiversity conservation planning, place a greater emphasis than the Omernik or Bailey systems on floral and faunal differences between regions. The WWF classification defines an ecoregion as: A large area of land or water that contains a geographically distinct assemblage of natural communities that: Share a large majority of their species and ecological dynamics. According to WWF, the boundaries of an ecoregion approximate the original extent of the natural communities prior to any major recent disruptions or changes. WWF has identified 867 terrestrial ecoregions, 450 freshwater ecoregions across the Earth; the use of the term ecoregion is an outgrowth of a surge of interest in ecosystems and their functioning. In particular, there is awareness of issues relating to spatial scale in the study and management of landscapes, it is recognized that interlinked ecosystems combine to form a whole, "greater than the sum of its parts". There are many attempts to respond to ecosystems in an integrated way to achieve "multi-functional" landscapes, various interest groups from agricultural researchers to conservationists are using the "ecoregion" as a unit of analysis.
The "Global 200" is the list of ecoregions identified by WWF as priorities for conservation. Ecologically based movements like bioregionalism maintain that ecoregions, rather than arbitrarily defined political boundaries, provide a better foundation for the formation and governance of human communities, have proposed ecoregions and watersheds as the basis for bioregional democracy initiatives. Terrestrial ecoregions are land ecoregions, as distinct from marine ecoregions. In this context, terrestrial is used to mean "of land", rather than the more general sense "of Earth". WWF ecologists divide the land surface of the Earth into 8 major ecozones containing 867 smaller terrestrial ecoregions; the WWF effort is a synthesis of
Minnesota Historical Society
The Minnesota Historical Society is a nonprofit educational and cultural institution dedicated to preserving the history of the U. S. state of Minnesota. It was founded by the territorial legislature in 1849 a decade before statehood; the Society is named in the Minnesota Constitution. It is headquartered in the Minnesota History Center in downtown St. Paul. Although its focus is on Minnesota history it is not constrained by it, its work on the North American fur trade has been recognized in Canada as well. MNHS holds a collection of nearly 550,000 books, 37,000 maps, 250,000 photographs, 225,000 historical artifacts, 950,000 archaeological items, 38,000 cubic feet of manuscripts, 45,000 cubic feet of government records, 5,500 paintings and drawings. MNopedia: The Minnesota Encyclopedia, is since 2011 an online "resource for reliable information about significant people, places and things in Minnesota history", funded through a Legacy Amendment Arts and Cultural Heritage Fund grant and administered by the Minnesota Historical Society.
The Minnesota Historical Society operates 31 historic sites and museums, 26 of which are open to the public. MNHS manages 14 sites directly and 10 in partnerships where the society maintains the resources and provides funding. Five sites are being held for preservation but are closed to public access, two are self-guided sites with interpretive signage. Seven of the sites are National Historic Landmarks and 16 others are on the National Register of Historic Places. Seven sites lie within Minnesota state parks, three are elements of the Mississippi National River and Recreation Area. "Journals and other documents of the Minnesota Historical Society". Minnesota Historical Society / Internet Archive. Retrieved November 24, 2012; these publications are described in more detail in an online format, at the MHC's own Digital History Books page Minnesota Historical Society Placeography – wiki operated by the Minnesota Historical Society This article incorporates text from MNopedia, licensed under the Creative Commons Attribution-ShareAlike 3.0 Unported License
The United States of America known as the United States or America, is a country composed of 50 states, a federal district, five major self-governing territories, various possessions. At 3.8 million square miles, the United States is the world's third or fourth largest country by total area and is smaller than the entire continent of Europe's 3.9 million square miles. With a population of over 327 million people, the U. S. is the third most populous country. The capital is Washington, D. C. and the largest city by population is New York City. Forty-eight states and the capital's federal district are contiguous in North America between Canada and Mexico; the State of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The State of Hawaii is an archipelago in the mid-Pacific Ocean; the U. S. territories are scattered about the Pacific Ocean and the Caribbean Sea, stretching across nine official time zones. The diverse geography and wildlife of the United States make it one of the world's 17 megadiverse countries.
Paleo-Indians migrated from Siberia to the North American mainland at least 12,000 years ago. European colonization began in the 16th century; the United States emerged from the thirteen British colonies established along the East Coast. Numerous disputes between Great Britain and the colonies following the French and Indian War led to the American Revolution, which began in 1775, the subsequent Declaration of Independence in 1776; the war ended in 1783 with the United States becoming the first country to gain independence from a European power. The current constitution was adopted in 1788, with the first ten amendments, collectively named the Bill of Rights, being ratified in 1791 to guarantee many fundamental civil liberties; the United States embarked on a vigorous expansion across North America throughout the 19th century, acquiring new territories, displacing Native American tribes, admitting new states until it spanned the continent by 1848. During the second half of the 19th century, the Civil War led to the abolition of slavery.
By the end of the century, the United States had extended into the Pacific Ocean, its economy, driven in large part by the Industrial Revolution, began to soar. The Spanish–American War and World War I confirmed the country's status as a global military power; the United States emerged from World War II as a global superpower, the first country to develop nuclear weapons, the only country to use them in warfare, a permanent member of the United Nations Security Council. Sweeping civil rights legislation, notably the Civil Rights Act of 1964, the Voting Rights Act of 1965 and the Fair Housing Act of 1968, outlawed discrimination based on race or color. During the Cold War, the United States and the Soviet Union competed in the Space Race, culminating with the 1969 U. S. Moon landing; the end of the Cold War and the collapse of the Soviet Union in 1991 left the United States as the world's sole superpower. The United States is the world's oldest surviving federation, it is a representative democracy.
The United States is a founding member of the United Nations, World Bank, International Monetary Fund, Organization of American States, other international organizations. The United States is a developed country, with the world's largest economy by nominal GDP and second-largest economy by PPP, accounting for a quarter of global GDP; the U. S. economy is post-industrial, characterized by the dominance of services and knowledge-based activities, although the manufacturing sector remains the second-largest in the world. The United States is the world's largest importer and the second largest exporter of goods, by value. Although its population is only 4.3% of the world total, the U. S. holds 31% of the total wealth in the world, the largest share of global wealth concentrated in a single country. Despite wide income and wealth disparities, the United States continues to rank high in measures of socioeconomic performance, including average wage, human development, per capita GDP, worker productivity.
The United States is the foremost military power in the world, making up a third of global military spending, is a leading political and scientific force internationally. In 1507, the German cartographer Martin Waldseemüller produced a world map on which he named the lands of the Western Hemisphere America in honor of the Italian explorer and cartographer Amerigo Vespucci; the first documentary evidence of the phrase "United States of America" is from a letter dated January 2, 1776, written by Stephen Moylan, Esq. to George Washington's aide-de-camp and Muster-Master General of the Continental Army, Lt. Col. Joseph Reed. Moylan expressed his wish to go "with full and ample powers from the United States of America to Spain" to seek assistance in the revolutionary war effort; the first known publication of the phrase "United States of America" was in an anonymous essay in The Virginia Gazette newspaper in Williamsburg, Virginia, on April 6, 1776. The second draft of the Articles of Confederation, prepared by John Dickinson and completed by June 17, 1776, at the latest, declared "The name of this Confederation shall be the'United States of America'".
The final version of the Articles sent to the states for ratification in late 1777 contains the sentence "The Stile of this Confederacy shall be'The United States of America'". In June 1776, Thomas Jefferson wrote the phrase "UNITED STATES OF AMERICA" in all capitalized letters in the headline of his "original Rough draught" of the Declaration of Independence; this draft of the document did not surface unti
A tributary or affluent is a stream or river that flows into a larger stream or main stem river or a lake. A tributary does not flow directly into a ocean. Tributaries and the main stem river drain the surrounding drainage basin of its surface water and groundwater, leading the water out into an ocean. A confluence, where two or more bodies of water meet together refers to the joining of tributaries; the opposite to a tributary is a distributary, a river or stream that branches off from and flows away from the main stream. Distributaries are most found in river deltas. "Right tributary" and "left tributary" are terms stating the orientation of the tributary relative to the flow of the main stem river. These terms are defined from the perspective of looking downstream. In the United States, where tributaries sometimes have the same name as the river into which they feed, they are called forks; these are designated by compass direction. For example, the American River receives flow from its North and South forks.
The Chicago River's North Branch has the East and Middle Fork. Forks are sometimes left. Here, the "handedness" is from the point of view of an observer facing upstream. For instance, Steer Creek has a left tributary, called Right Fork Steer Creek. Tributaries are sometimes listed starting with those nearest to the source of the river and ending with those nearest to the mouth of the river; the Strahler Stream Order examines the arrangement of tributaries in a hierarchy of first, second and higher orders, with the first-order tributary being the least in size. For example, a second-order tributary would be the result of two or more first-order tributaries combining to form the second-order tributary. Another method is to list tributaries from mouth to source, in the form of a tree structure, stored as a tree data structure. A gallery of major river basins with tributaries Estuary
Google Earth is a computer program that renders a 3D representation of Earth based on satellite imagery. The program maps the Earth by superimposing satellite images, aerial photography, GIS data onto a 3D globe, allowing users to see cities and landscapes from various angles. Users can explore the globe by using a keyboard or mouse; the program can be downloaded on a smartphone or tablet, using a touch screen or stylus to navigate. Users may use the program to add their own data using Keyhole Markup Language and upload them through various sources, such as forums or blogs. Google Earth is able to show various kinds of images overlaid on the surface of the earth and is a Web Map Service client. In addition to Earth navigation, Google Earth provides a series of other tools through the desktop application. Additional globes for the Moon and Mars are available, as well as a tool for viewing the night sky. A flight simulator game is included. Other features allow users to view photos from various places uploaded to Panoramio, information provided by Wikipedia on some locations, Street View imagery.
The web-based version of Google Earth includes Voyager, a feature that periodically adds in-program tours presented by scientists and documentarians. Google Earth has been viewed by some as a threat to privacy and national security, leading to the program being banned in multiple countries; some countries have requested that certain areas be obscured in Google's satellite images areas containing military facilities. The core technology behind Google Earth was developed at Intrinsic Graphics in the late 1990s. At the time, the company was developing 3D gaming software libraries; as a demo of their 3D software, they created a spinning globe that could be zoomed into, similar to the Powers of Ten film. The demo was popular, but the board of Intrinsic wanted to remain focused on gaming, so in 1999, they created Keyhole, Inc. headed by John Hanke. Keyhole developed a way to stream large databases of mapping data over the internet to client software, a key part of the technology, acquired patchworks of mapping data from governments and other sources.
The product, called "Keyhole EarthViewer", was sold on CDs for use in fields such as real estate, urban planning and intelligence. Despite making a number of capital deals with Nvidia and Sony, the small company was struggling to make payroll, employees were leaving. Fortunes for the company changed in early 2003 when CNN received a discount for the software in exchange for placing the Keyhole logo on-air whenever the map was used. Keyhole did not expect it would amount to more than brief 5 or 10 second prerecorded animation clips, but it was used extensively by Miles O'Brien live during the 2003 invasion of Iraq, allowing CNN and millions of viewers to follow the progress of the war in a way that had never been seen before. Public interest in the software exploded and Keyhole servers were not able to keep up with demand. Keyhole was soon contacted by the Central Intelligence Agency's venture capital firm, In-Q-Tel, the National Geospatial-Intelligence Agency, for use with defense mapping databases, which gave Keyhole a much-needed cash infusion.
Intrinsic Graphics was sold in 2003 to Vicarious Visions after its gaming libraries did not sell well, its core group of engineers and management transitioned to Keyhole with Hanke remaining at the head. At the time, Google was finding that over 25% of its searches were of a geospatial character, including searches for maps and directions. In October 2004, Google acquired Keyhole as part of a strategy to better serve its users. Google Earth's imagery is displayed on a digital globe, which displays the planet's surface using a single composited image from a far distance. After zooming in far enough, the imagery transitions into different imagery of the same area with finer detail, which varies in date and time from one area to the next; the imagery is retrieved from satellites or aircraft. Before the launch of NASA and the USGS's Landsat 8 satellite, Google relied on imagery from Landsat 7, which suffered from a hardware malfunction that left diagonal gaps in images. In 2013, Google used datamining to remedy the issue, providing what was described as a successor to the Blue Marble image of Earth, with a single large image of the entire planet.
This was achieved by combining multiple sets of imagery taken from Landsat 7 to eliminate clouds and diagonal gaps, creating a single "mosaic" image. Google now uses Landsat 8 to provide imagery with greater frequency. Imagery is hosted on Google's servers, which are contacted by the application when opened, requiring an Internet connection. Imagery resolution ranges from 15 meters of resolution to 15 centimeters. For much of the Earth, Google Earth uses digital elevation model data collected by NASA's Shuttle Radar Topography Mission; this creates the impression of three-dimensional terrain where the imagery is only two-dimensional. Every image created from Google Earth using satellite data provided by Google Earth is a copyrighted map. Any derivative from Google Earth is made from copyrighted data which, under United States Copyright Law, may not be used except under the licenses Google provides. Google allows non-commercial personal use of the images as long as copyrights and attributions are preserved.
By contrast, images created with NASA's globe software World Wind use The Blue Marble, Landsat, or USGS imagery, each of, in the public domain. In version 5.0, Google introduced Historical Imagery. Clicking the clock icon in the toolbar opens a time slider, which marks the tim
DeLorme is a producer of personal satellite tracking and navigation technology. The company's main product, inReach, integrates satellite technologies. InReach provides the ability to send and receive text messages anywhere in the world by using the Iridium satellite constellation. By pairing with a smart phone, navigation is possible with access to free downloadable topographic maps and NOAA charts. On February 11, 2016, the company announced that it had been purchased by Garmin, a multinational producer of GPS products and services. DeLorme produces printed atlas and topographic software products; the company combines digital technologies with human editors to verify travel information and map details. DeLorme Atlas & Gazetteer is a complement to a vehicle’s GPS or online mapping site, allowing a traveler to browse and highlight the anticipated route and the possible activities or excursions along the way or at the destination. DeLorme’s Topo software is one of the sources of North American trail, logging road and terrain data for outdoor enthusiasts.
Topo 10 has US and Canada topographic maps and elevation data with more than four million places of interest. Topo includes comprehensive park, lake and stream data for all 50 states. DeLorme continues to sell paper atlases, with more than 20 million copies sold to date. Founded in 1976, DeLorme is headquartered in Yarmouth, is home to Eartha, the world's largest revolving globe; the company was founded in 1976 by David DeLorme, being frustrated over obsolete back-country maps of the Moosehead Lake region of Maine, vowed to create a better map of Maine. DeLorme combined state highway and town maps as well as federal surveys to produce the Maine Atlas and Gazetteer, printed in a large-format book with an initial printing of 10,000, which he marketed out of his car; the Gazetteer, which listed bicycle trails and kayaking trips, museum and historic sites, proved quite successful. The company expanded to 75 employees in 1986, working from a Quonset hut in Freeport, producing maps for New England and upstate New York.
In 1987, the company produced a CD with detailed topographic map data of the entire world. In 1991, DeLorme began vending Street Atlas USA on a single CD-ROM, becoming the most popular street-map CD in the United States, as well as one of the first mass consumer CD-ROM software products of any kind. By 1995, DeLorme had 44 percent of the market share for CD maps; the same year the company partnered with the American Automobile Association to produce the AAA Map'n Go, the first mapping product to generate automatic routing. They introduced the DeLorme GPS receiver to work with its maps. In 1996, it introduced its maps into the PDA environment via Palm. In 1997, the company relocated to a new corporate campus in Yarmouth, that features a giant model of the world, named Eartha, the largest rotating globe in the world; the company has provided complimentary geographic educational sessions for thousands of school children over the years and the public is welcome to visit and see Eartha from the three-story balconies.
In 1999, DeLorme introduced 3D TopoQuad DVD and CD products, which include digitized U. S. topographic maps. In 2001, XMap professional GIS map program was produced on CD, an expanded XMap was released in 2002, modified to provide GPS functionality to Palm OS and Pocket PC. In 2005, DeLorme became the first company to sell a USB GPS device, the Earthmate GPS LT-20. At the same time, it began offering downloadable satellite and USGS 7.5-minute quads that could be overlaid on its maps using a new NetLink feature. Earlier models of Earthmate were among the first GPS receivers tethered to laptops. In 2006/2007, the firm introduced its first full-featured GPS standalone receiver, the Earthmate GPS PN-20. During 2008, the company continued expanding its handheld GPS line with the Earthmate GPS PN-40 model. DeLorme began selling OEM GPS modules allowing other manufacturers to add GPS to their products. In addition, the company began selling data to businesses. In 2009, DeLorme released D. A. E.. It is the first worldwide GPS accurate topographical map with a scale of 1 to 50,000.
D. A. E. is the official world map for the Australian militaries. It is a virtual globe of the earth, 1,000 feet in diameter. In 2011, DeLorme launched "InReach," a worldwide satellite communication and SOS device that fits in your pocket, it works in the middle of the ocean, at the north pole, through triple canopy jungles, has been proven on the summit of Mt. Everest. Through the SOS feature, 3 rescues a day occur around the world. On February 11, 2016, GPS products and services company Garmin announced it had agreed to purchase DeLorme; the announcement stated. Another announcement confirmed. Maps of the United States Geospatial Trail maps DeLorme website LaptopGPSworld.com: Review of DeLorme Street Atlas 2008 inReach website Facebook: DeLormeGPS Twitter: DeLormeGPS