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Geographic Names Information System

Geographic Names Information System is a earth science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Geographic Names Information System rather than just read about it. In short: The Geographic Names Information System (GNIS) is a database of name and location information about more than two million physical and cultural features, encompassing the United States; the associated states of the Marshall Islands, Micronesia, Palau, and Antarctica. It is a type of gazetteer.

Geographic Names Information System — main illustration
Geographic Names Information System — illustration

Key takeaways

  • Geographic Names Information System belongs to earth science; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Geographic Names Information System to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Geographic Names Information System from memory before moving on to harder problems.

Reference excerpt

The Geographic Names Information System (GNIS) is a database of name and location information about more than two million physical and cultural features, encompassing the United States; the associated states of the Marshall Islands, Micronesia, Palau, and Antarctica. It is a type of gazetteer. It was developed by the United States Geological Survey (USGS) in cooperation with the United States Board on Geographic Names (BGN) to promote the standardization of feature names. Data were collected in two phases. A third phase was considered, which would have handled name changes where local usages differed from maps, it was never begun. The database is part of a system that includes topographic map names and bibliographic references. The names of books and historic maps that confirm the feature or place name are cited. Variant names, alternatives to official federal names for a feature, are also recorded. Each feature receives a permanent, unique feature record identifier, sometimes called the GNIS identifier. The database never removes an entry, "except in cases of obvious duplication."

Original purposes The GNIS was originally designed for four major purposes: to eliminate duplication of effort at various other levels of government that were already compiling geographic data, to provide standardized datasets of geographic data for the government and others, to index all of the names found on official U.S. government federal and state maps, and to ensure uniform geographic names for the federal government.

Phase 1 Phase 1 lasted from 1978 to 1981, with a precursor pilot project run over the states of Kansas and Colorado in 1976, and produced 5 databases. It excluded several classes of feature because they were better documented in non-USGS maps, including airports, the broadcasting masts for radio and television stations, civil divisions, regional and historic names, individual buildings, roads, and triangulation depot names. The databases were initially available on paper (2 to 3 spiral-bound volumes per state), on microfiche, and on magnetic tape encoded (unless otherwise requested) in EBCDIC with 248-byte fixed-length records in 4960-byte blocks. The feature classes for association with each name included (for examples) "locale" (a "place at which there is or was human activity" not covered by a more specific feature class), "populated place" (a "place or area with clustered or scattered buildings"), "spring" (a spring), "lava" (a lava flow, kepula, or other such feature), and "well" (a well). Mountain features would fall into "ridge", "range", or "summit" classes. A feature class "tank" was sometimes used for lakes, which was problematic in several ways. This feature class was undocumented, and it was (in the words of a 1986 report from the Engineer Topographic Laboratories of the United States Army Corps of Engineers) "an unreasonable determination", with the likes of Cayuga Lake (in upstate New York) being labelled a "tank". The USACE report assumed that "tank" meant "reservoir", and observed that often the coordinates of "tanks" were outside of their boundaries and were "possibly at the point where a dam is thought to be".

National Geographic Names database The National Geographic Names database (NGNDB hereafter) was originally 57 computer files, one for each state and territory of the United States (except Alaska which got two) plus one for the District of Columbia. The second Alaska file was an earlier database, the Dictionary of Alaska Place Names that had been compiled by the USGS in 1967. A further two files were later added, covering the entire United States and that were abridged versions of the data in the other 57: one for the 50,000 most well known populated places and features, and one for most of the populated places. The files were compiled from all of the names to be found on USGS topographic maps, plus data from various state map sources. In phase 1, elevations were recorded in feet only, with no conversion to metric, and only if there was an actual elevation recorded for the map feature. They were of either the lowest or highest point of the feature, as appropriate. Interpolated elevations, calculated by interpolation between contour lines, were added in phase 2. Names were the official name, except where the name contained diacritic characters that the computer file encodings of the time could not handle (which were in phase 1 marked with an asterisk for update in a later phase). Generic designations were given after specific names, so (for examples) Mount Saint Helens was recorded as "Saint Helens, Mount", although cities named Mount Olive, not actually being mountains, would not take "Mount" to be a generic part and would retain their order "Mount Olive". The primary geographic coordinates of features which occupy an area, rather than being a single point feature, were the location of the feature's mouth, or of the approximate center of the area of the feature. Such approximate centers were "eye-balled" estimates by the people performing the digitization, subject to the constraint that centers of areal features were not placed within other features that are inside them. alluvial fans and river deltas counted as mouths for this purpose. For cities and other large populated places, the coordinates were taken to be those of a primary civic feature such as the city hall or town hall, main public library, main highway intersection, main post office, or central business district regardless of changes over time; these coordinates are called the "primary point". Secondary coordinates were only an aid to locating which topographic map(s) the feature extended across, and were "simply anywhere on the feature and on the topographic map with which it is associated". River sources were determined by the shortest drain, subject to the proximities of other features that were clearly related to the river by their names.

… excerpt ends here. Continue reading the full article.

Illustrations

Geographic Names Information System: The logo of the United States Geological Survey (USGS)
The logo of the United States Geological Survey (USGS)

Worked examples

Example 1 — a first encounter with Geographic Names Information System

Start with the simplest possible case. Write down what Geographic Names Information System claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In earth science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Geographic Names Information System before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Geographic Names Information System ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Geographic Names Information System

In research
Geographic Names Information System appears in earth science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Geographic Names Information System in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Geographic Names Information System is common in secondary-school and first-year university syllabi. It links to neighbouring topics Gazetteers, Geocodes, Geographical databases in the United States, so understanding it makes those chapters shorter.
In everyday life
Look for Geographic Names Information System outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.
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How to study Geographic Names Information System in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Geographic Names Information System means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Geographic Names Information System out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Geographic Names Information System in simple terms?

The Geographic Names Information System (GNIS) is a database of name and location information about more than two million physical and cultural features, encompassing the United States; the associated states of the Marshall Islands, Micronesia, Palau, and Antarctica. It is a type of gazetteer.

Why does Geographic Names Information System matter?

Because it connects several earth science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Geographic Names Information System?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Geographic Names Information System.

Tags

  • Gazetteers
  • Geocodes
  • Geographical databases in the United States
  • Geography of the United States
  • Government databases in the United States
  • Public domain databases
  • United States Geological Survey

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