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Geospatial Purpose

Describe geospatial coverage of resources where resources are:– Web-based activities, modules etc.– Datasets– Model output– Visuals (maps, satellite imagery)

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Other Geospatial Characteristics

Meant to provide general coverage with some details in a broad sense

Does not describe coverage of individual variables of datasets or model output

Is independent of temporal characteristics

Development period - Jan 2000 to June 2002 with some implementation fixes in Dec 2002

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Geospatial Development Team

DPC - Katy Ginger, Holly Devaul ADL/ADEPT - Linda Hill, Anita Coleman, Tim Tierney

and sometimes Greg and David V. Colorado School of Mines - Tom Boyd NASA - Shelley Olds Other sources - Ontario Information and Tech.

Standards - Metadata Content Spec; DC spec Geosciences represented - geophysics,

atmospheric science

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Geospatial in the Framework (1)

1. Overarching Bounding Box - a single overall, geometric footprint on the surface of a planet or moon in our solar system described with a 4 vortex box in geographic latitude and longitude

2. Detailed Geometries - detailed geometric footprints (polygons, lines, points) on the surface of a planet or moon in our solar system using multiple latitude and longitude tuples; Overarching Bounding Box is required

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Geospatial in the Framework (2)

3. Elevation - the vertical min & max of footprints (overarching box & detailed geos) with reference to ground or datum level

4. Planet or other body - the planet or body in our solar system for the geospatial footprint

5. Place-name tied to coordinates - the name of a location that is specified by a footprint (e.g. N=41°, S=37°, E=-102°, W=-109° is Colorado, United States

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Geospatial in the Framework (3)

6. Place-name not tied to coordinates - location name not specified by a geospatial footprint; (keyword searching only)

7. Event-name tied to coordinates - the name of an event that occurred in the area specified by the geospatial footprint (e.g. N=45°, S=22°, E=-62°, W=-86° is Hurricane Fran in 1996

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Geospatial in the Framework (4)

8. Event name not tied to coordinates - an event within an area that is not specified by a footprint; (keyword searching only)

9. Objects in space - the location of objects (e.g. nebulas) that are not within our solar system; described using the conventions of:

– Right ascension (0 <= hours <= 24)– Declination (-90 <= degrees <= 90)– Epoch (50 year steps to redraw celestial grid due to equinox

progress. epoch1950.0 / epoch2000.0)

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Geospatial in the Framework (5)

10. Coordinate system - – a frame of reference specifying the location of an

object in ‘space’– DLESE uses overarching bounding box so only

Geographic latitude and longitude can be the coordinate system

– visuals, raw and gridded data use coordinate system

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Geospatial in the Framework (6)

11. Datum - base reference in a coordinate system; the position of an initial point of origin and orientation of an ellipsoid that models the surface of the earth in the region of interest. Datums apply to coordinate systems

– Horizontal - NAD27, NAD83, ATS77 – Vertical - Sea level ,CGD28-CDN, NAVD29-USA,

NAVD88, IGLD88 – Global - WGS72, WGS84 (GPS use), PZ-90 – Other and Unknown is allowed

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Geospatial in the Framework (7)

12. Projection - – systematic presentation (think 2-D maps) of

objects on the Earth or the celestial sphere using coordinate lines on a flat surface

– different projections represent different parts of the Earth better (polar stereographic versus satellite)

– only visuals, not gridded or raw data, use projection

– Other, Unknown and Does not apply are allowed

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Geospatial in the Framework (8)

13. Latitudes and Longitudes - – West longitudes: -180 to 0– East longitudes: 0 to 180– North latitudes: 0 to 90– South latitudes: -90 to 0

All in decimal degrees and not degrees/minutes

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Temporal Purpose & Characteristics

Describe date/time characteristics of resources Like geospatial not meant for individual

variables rather a broad sense of time Is independent of geospatial coverage Development period - May 2002 to Dec 2002 Development team - Katy Ginger, Ethan Davis

(thredds) and the ISO 8601 standard

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Temporal in the Framework (1)

A. Time AD - the ability to describe date/time ranges like:

– 1965-06-23 12:00:00Z to 1974– 1492 to 1505 either with time (in UTC) or not– Begin and end times must be specified

B. Time AD to present - the ability to describe date ranges like:

– 1996 to Present either with time (in UTC) or not– Begin and end times must be specified

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Temporal in the Framework (2)

C. Time BC - the ability to describe date ranges:– -8700 to -2500 BC – No time allowed

D. Time relative - describe time ranges like:– 30 days ago to 0 days ago (present) – 1.2 billion years ago to 1.0 thousand years ago – 100 years forward to 1000 years forward (for use in

modeling climate change)– Begin & end times must be specified

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Temporal in the Framework (3)

E. Named time period - the ability to associate specified date/time information with a named time period like 1920 to 1930, e.g. 'The Roaring 20's'. Sources for the name must be indicated, e.g., 'cataloger provided'.

F. Simple time period - the ability to name a recurring named time period without associating specified date/time information, e.g. 'spring semester', 'fall'