Distributed Geolibraries Spatial Information Resources, Summary of a Workshop (1999) / Chapter Skim
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5 Building Distributed Geolibraries
5 Building Distributed Geolibraries
Pages 73-88
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From page 73... ...
It is impossible to be precise, of course, because of uncertainties surrounding future technologies, because the outcomes of research are in principle impossible to anticipate, and because many issues can only be resolved by constructing and working with prototypes. Given these constraints, this report attempts to address a number of key questions and to find answers where possible: · What will it take to build distributed geolibraries?
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From page 74... ...
The Panel' vision of distributed geolibraries views them as a primary distribution mechanism for getting geospatial data and geographic knowledge resources into the hands of all stakeholders. Traditionally, the primary source of geospatial data in the United States, as in many other countries, has been the national mapping agency.
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From page 75... ...
The metadata standard developed by the Federal Geographic Data Committee (FGDC) and known as the Content Standards for Digital Geospatial Metadata (http://www.fg~c.gov)
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From page 76... ...
is developing a wide range of specifications for geospatial objects to support interoperation and is strongly supported by the GIS software industry. Other standards of relevance to distributed geolibraries include those under discussion on intellectual property rights in digital data, standards of geospatial data quality, definitions of geographic feature types, and general mapping standards.
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From page 77... ...
In distributed geolibraries an essential authority is the gazetteer. A distributed geolibrary's gazetteer will differ in several key respects from the traditional version found in the back pages of atlases: Support for extents, defined as the bounding coordinates of place-names.
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From page 78... ...
In the geoinformation case, various kinds of authorities would be useful: lists of standard feature types, standard data themes, standard attribute definitions. For example, it would be useful if the meaning of vegetation and associated terms could be standardized, and much effort by the FGDC has been devoted over the past few years toward this end.
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From page 79... ...
Thus, a user ought to be able to access data sets in different projections and based on different datums and expect the system to handle the differences automatically. Such transparency is not yet available in standard geospatial software products ant!
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From page 80... ...
Unfortunately, the process of metadata creation for digital geospatial data can be as lengthy and labor intensive as its traditional equivalent. The task of creating a full metadata record for a geospatial data set using the FGDC metadata standard can be much greater than the task of cataloging a simple book.
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From page 81... ...
Information about the Earth's surface is naturally conceptualized as belonging to the surface, and globes, which are actual seated representations of the Earth, provide a familiar and easily understood information source. The notion of doing the same in the digital world, of presenting information as if it were actually located on the surface of the globe, is termed the Digital Earth metaphor, and lies behind the idea described earlier in Chapter 2.
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From page 82... ...
RESEARCH NEEDS Many of the topics discussed in this report fall under the heading of "things we do not yet know how to do." In some cases, such as the building of a distributed geolibrary itself, there may be no obviously missing piece of theory or understanding; rather, it may be that we have not yet tried and that given sufficient resources the necessary knowledge will be available. But other items require more focused research.
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From page 83... ...
Distributed geolibraries will be one of a growing number of applications that depend on the ability to register multiple data sets quickly and easily and to remove obvious discrepancies. Finding 13 ~ ~ ; ;~ ~ .~ ~ ~ ~ The success of a distributed geolibrary W111: be largely dependent on they ability toil integrate information ava~lable~abo~a~place.~That ability is severely impeded today~by differences~in~formats al standards, access mechanisms, and organizationally; Euchres.
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From page 84... ...
· Digital Government. NSF recently announced research opportunities in a new program to build stronger ties between the research community in computer and information science and engineering and various government departments with very significant investments in systems and data integration (NSF Program Announcement 98-1211.
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From page 85... ...
INSTITUTIONAL NEEDS Although elements of a distributed geolibrary already exist in the form of prototype clearinghouses and other projects, it is easy to lose sight of the broader concept and the degree to which it represents a radical departure from current and past practices as reflected in our institutions and their accepted functions. More specifically: · Traditional production and dissemination of geoinformation have been centralized, as functions of the upper levels of government.
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From page 86... ...
" Producers and distributors of geospatial data could make it much easier to integrate different types of data. The USGS, for example, could make it easier to obtain digital elevation data, digital topographic data, and digital orthophoto data for the same area.
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From page 87... ...
discuss this relationship between the needs of the geospatial data and the broader institutional setting of the evolving digital library. That relationship is complex, and it is clear that distributed geolibraries are part of a larger vision of the digital library of the future.
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From page 88... ...
without direct knowledge of their contents, through the mechanisms used by the library to abstract and catalog. One might measure the progress of a distributed geolibrary on this basis, by developing indicators of the amount of work required on the part of the user to find a given item of information.
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