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Manitoba Land Initiative
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Rev. 2008-12-16 10:39
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MLI Data Standards Committee
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| Accepted
Standards |
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| Background |
| Parcel
Identification Numbers - PINs |
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| Metadata
Standards: |
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The Value of Metadata |
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MLI Minimum acceptable Metadata Standard |
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Metadata Keywords |
| Datum
Standard |
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| Standards
- Work in progress |
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| Back to
Home Page |
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| On June 04 1999, the Deputy
Minister Committee of departments involved in land related information systems gave
the mandate to the Manitoba Land Initiative (MLI) Committee to develop and recommend a
structure for a government-wide framework for the management of land-related
information. Office of Information Technology was delegated to lead and co-ordinate
this initiative.
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January 6, 2000
The basic principle behind a PIN is that each polygon/parcel has a unique identifier that does not use
other land references. It basically provides a pure identifier for each polygon; this PIN reference can
then be used as the key to any other attribute information that need be attached to it.
The standard for the PIN (Polygon Identifier/Parcel Identifier) was put forth in the M.L.R.I.S. Data
Standards in 1990.
“The recommended standard for identification of ownership parcels and survey parcels in a
Manitoba Land related Information System is a unique, computer generated, numeric identifier
consisting of 8 or 9 digits including preferably a check digit. Ownership and survey parcel
identification numbers shall be issued by the agency responsible for creating the parcel”
The Land Information Division has reviewed a number of options relating to the standard and has
chosen to implement a 9 digit PIN with a 9th digit being a checksum. The 8 digit model will allow for
the generation and maintenance of 100,000,000 (-1) PINs with a value greater than 0.
i.e. the 8 digit PIN for a value of 11 would be 000000112 (the checksum would be calculated
as 0+0+0+0+0+0+1+1=2 (2), for a value of 00495268 the calculation would be:
0+0+4+9+5+2+6+8 = 34 3+4 = 7(7) with a resulting PIN of 004952687.
The new PIN number is being implemented for the cadastral mapping products issued by the Land
Information Division. The current roll out process is:
1. All new digital parcel-mapping products generated through the Land Information Division will
be based on the new PIN. The Brandon property mapping data sets are currently being
updated. These data sets will be the first ones issued with the new PINs.
2. Other existing digital parcel datasets will be converted to the new PIN system at the time of
their next maintenance or update cycle. The retired PIN will be retained as a historic record in
the parcel attribute databases.
Application
The PIN has been associated with a graphic of a parcel polygon. A parcel polygon identified with a
PIN need not have a graphic polygon with an identical PIN attached. The parcel/polygon PIN can have
many attribute records attached using the PIN as the key. For example: Survey Polygon, Ownership,
DLS description & information, Survey Plan, River/Parish lots, Assessment, etc.
Benefits
A number of different "standards" have been put in place by various agencies over the years for uniquely
identifying polygons and/or land parcels. As an example, The Dominion Land Survey (DLS) coding:
Meridian – Range – Township - Section is coded in every imaginable sequence, as separate fields,
concatenated into one small to large field etc. Coding systems for Survey Plans, Parish lots etc. also
share the same coding ambiguities. To add to this confusion and ambiguity, some systems attempt to
generalize all/some of the above “standards” and “cram” them into a single field. Attached is an
example of the previous LID "standard" field coding, titled 'Property identifiers for the Polygon
creation process'. Clarity was not one of its attributes. One of the latest polygon identification
standards is in the ¼ Section grid for Manitoba. The ID takes the form “M RRTTTSSQQ” e.g. “E
0400919NE” an example of this ID is attached (form showing duplicates in data set and a map
showing the duplicate descriptions for Ritchot). The failure of this from of
generalization is apparent. In a universal PIN application, the DLS attribute entry for a PIN is done once with enough
fields to properly describe the parcel and need not be reproduced in a myriad of formats on different
systems. The same would apply for Parish lots, Registered plans, Ownership etc.
PIN Allocation
Of primary concern is the issuing of new unique PINs. In order for a Universal PIN system to
successfully operate, there can be no duplicate PIN numbers issued. Until a central electronic PIN
allocation system is established, numbers can be allocated to various Departments and Agencies in
controlled blocks. Some concern has been raised about implicitly building intelligence into the PIN by
allocating large blocks of numbers to a particular agency. The current mapping products in the LID are
given a block of sequential numbers due to software considerations; however, any subsequent revisions
or updates will be allocated in small blocks of sequential numbers or single and not necessarily
sequential numbers. A similar process can be put in place for other agencies. All allocations are
recorded in a SQL Server table "IDAllocations”, fields include: Entity group (Registered Plan Polygon,
Ownership Polygon, etc.), range of allocated numbers, name user, time and date stamp, project name,
etc.
It is proposed that the Land Information Division co-ordinate the allocation of the PINs.
PIN Retirement or Deletion & Tracking
The distribution of updated Cadastral datasets will include lists of PINs that are added and deleted since
the previous version of the dataset. This will allow users to select the polygon records in their databases
which should be retired and will also allow them to identify which records will have be added along with
their agency-specific attribute data. They will also be able to use these lists to identify the changed
polygons in the graphics in order to perform the maintenance of their agency-specific graphical data.
Problems Associated with Geocoding Ids
Geocoding systems depend on inserting coordinates of objects into their identifiers . This is problematic
since coordinates are not static or permanent, and thus as the location of objects change, then the
identifiers should change with them. An example of a geocode for a location with coordinate of UTM
Northing = 5,557,614 and UTM Easting = 633,214 is:? since the mapping is localized, then we can strip off the higher level parts of the coordinates and
specify the geocode to the nearest 10km as follows: Northing = 57614, Easting = 33214 and the
geocode = 57614 + 33214 = 5761433214
The locations of objects may change in several ways, some of these are:
- readjustment of geodetic networks (the location of most land-based objects are determined
by reference to geodetic networks)
- change of geodetic datums (this occured in 1983) through better measurements of the surface of the
earth
- corrections or updates to measurements of dimensions of objects
As the coordinates change, then the geocodes must change as well, which means that all of the database
records that refer to the older geocodes must be changed too.
Another problem with geocodes is that two separate objects cannot share the same location since their
identifiers would thus be identical and the objects would not be separately identified.
Because of these problems the use of geocodes to identify objects is strongly discouraged.
General
The PIN system as proposed, should deal with most or all parcels that are of a survey nature. Other
Polygons of other agencies required for their own internal or business application can work in
conjunction with this PIN system. It is of major land management concern that as many agencies using
the same parcel of land describe it the same way. The current system seriously breaks down between
agencies and not all agencies and users have or will have the graphic tools to unscramble the current
situation through the use of graphics.
If there are any issues or concerns that you may have relating to the implementation of the PIN
standard, please contact Al Dakin at 945-6652 or Bob Bruce at 945-6636.
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Metadata
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Manitoba Conservation
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The Value of Metadata (A
NSDI report)
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Two very similar paintings of circus performers by Picasso from
1904 are put on the auction block; one brings tens of millions of
dollars, the other hundreds of thousands. What is the difference?
In one case, the ownership of the painting can be traced
through sales slips and auction house records back to the estate
of Picasso's dealer. The other painting appeared suddenly on the
art market. It looks almost identical, but lacking documentation,
how can one be sure it's authentic?
Just as a work of art can change hands many times, so can
geospatial data. Once created, data can travel almost
instantaneously through a network and be used for different kinds
of spatial analysis. Thus transformed, these data can be
retransmitted to another user. Change is the essence of geospatial
data in a networked environment. The word metadata shares the same
Greek root as the word metamorphosis. Meta means change and
metadata, or "data about data," describe the origins of
and track the changes to geospatial data.
Metadata can help the fisheries biologies, the graduate student
in geography, or the wildlife manager find and use geospatial
data, but metadata also benefits the primary creator of the data
by maintaining the value of the data and assuring its continued
use over a span of years.
What is metadata?
The concept of metadata is familiar to most people who deal
with spatial issues. A map legend is pure metadata. The legend
contains information about the publisher of the map, the
publication data, the map's scale and its accuracy, among may
other things. Metadata is simply that type of descriptive
information that is applied to a digital geospatial file. They're
a common set of terms and definitions to use when documenting
geospatial data. Most digital geospatial files now have some
associated metadata.
Why bother with metadata?
Metadata helps people who use geospatial data find the data
they need and determine how best to use it. Metadata benefits the
data producing organization as well. As personnel change in an
organization, undocumented data may lose its value. Later workers
may have little understanding of the contents and uses for a
digital data base and may find they can't trust results generated
from these data. Lack of knowledge about organizations' data can
lead to duplication of effort.
It may seem burdensome to add the cost of generating metadata
to the cost of data collection, but in the long run it's work it.
How can metadata be produced?
The information needed to create metadata is often readily
available when the data is collected. A small amount of time
invested at the beginning of a project may save money in the
future. Data producers and users cannot afford to be without
documented data. The initial expense of documenting data clearly
outweighs the potential costs of duplicated or redundant data
generation. Recently developed metadata standards provide a
systematic way to collect metadata.
Why use standards?
When producing a map, the cartographer must organize all the
descriptive information that goes into the map legend in a
particular format. Titles are put in a specific place, tic marks
are made a certain way, meters may be used instead of feet, and so
forth. Metadata standards are simply a common set of terms and
definitions that describe geospatial data.
What standards should be used?
The Federal Geographic Data Committee (FGDC) recently adopted
content standards for metadata. According to an Executive order
signed by President Clinton on April 11, 1994, all Federal
agencies will begin to use these standards to document newly
created geospatial data as of January, 1995 after receiving the
appropriate training. These standards provide a consistent
approach and format for the description of data characteristics.
The standards were developed over a two-year period, with
extensive review by professionals at all levels of government.
They provide a way for data users to know:
What data is available
Whether the data meets specific needs
Where to find the data
How to access the data
Because large amounts of Federal data will be available in
these standards, data managers from State and local governments
and private industry will have an incentive to adopt these
standards to document their own data.
The FGDC is also sponsoring the creation of a National
Geospatial Data Clearinghouse which will point users toward the
best spatial data for a particular project. The intent is not to
centralize all geographic data in one location, but to provide
links through the Internet to distributed sites where data are
produced or maintained. Managers who document data using the
metadata standards will provide these metadata to the National
Geospatial Data Clearinghouse so that users can easily find data.
Easier access to data will mean that a company's customers or an
agency's cooperators could be increased.
Why use metadata?
Twenty-five years ago, humans landed on the Moon. Data from
that era is still being used today, and it is reasonable to assume
that today's geospatial data could still be used in the year 2020
and beyond to study climate change, ecosystems, and other natural
processes. Metadata standards will increase the value of such data
by facilitating data sharing through time and space.
The value of Picasso's painting did not depend solely on his
having signed the work, a signature that could easily have been
forged. Information about the painting, where it came from and
where it had been, increased its value. So, when a manager
launches a new project, investing a small amount of time and
resources at the beginning will pay dividends in the future.
Metadata will help you protect the value of your organization's
intellectual assets.
For more information
If you would like to obtain training or seek information about
the FGDC metadata standards or the National Geospatial Data
Clearinghouse contact:
FGDC Secretariat c/o U.S. Geological Survey 590 National Center
Reston, Virginia 22092 Telephone: (703)648-5514 Facsimile:
(703)648-5755 Internet: gdc@usgs.gov
Anonymous ftp://fgdc.er.usgs.gov
ftp://fgdc.er.usgs.gov/gdc/html/fgdc.html
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MLI Minimum acceptable Metadata Standard
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All products must have Metadata containing FGDC Sections 1 & 7
as a minimum
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Guidance
for minimal metadata documentation of spatial data files created
by Manitoba Land Initiative data providers
Items in red
bold and italics like this are necessary to comply with the
Federal Geographic Data Committee (FGDC) standard.
Items in bold
like this are necessary if you are filling out the section they
are in. For example section 2.5, lineage, is not mandatory for the
FGDC, but is recommended by Manitoba Conservation GIS Section. If
you chose to complete that section you need to complete all the
items in this type (or fill in N/A or unknown) to comply with the
Federal Geographic Data Committee (FGDC) standard and related
software.
ITEMS IN CAPS
AND BOLD ARE NOT REQUIRED, BUT ARE ITEMS MANITOBA CONSERVATION GIS
STEERING COMMITTEE MEMBERS FEEL WOULD ADD A GREAT DEAL TO THE
DOCUMENTATION. WE WOULD LIKE PEOPLE TO DOCUMENT THEM FOR FWS
METADATA IF POSSIBLE.
There are a number of items in regular
print, some with numbers in front of them. Generally these are
headings, and are needed to run the data through a compiler to
create files to serve on the Internet or be searchable by the FGDC
search engine. If we can keep data consistent with the FGDC,
sharing the information with other agencies, partners, etc will be
much easier. Other items in regular print are sample data.
Any explanatory notes are in italics
General Notes on the Metadata
Sections
- Identification Information
(required)
Most of this section is
Mandatory
to comply with the FGDC
standard. It is basic identification information about the data
set you have created. The data set may be one or multiple files;
generally you will document one file at a time.
In some of the sections (for
example 1.3 - Time Period) you will need to chose the option
appropriate for your data and delete (if you are using the
template) or ignore (if you are using a program) the others.
This one is simple - you created the data on one day, several
days, or a range of days. If it's one file, it's probably one
day. Multiple files (like 1:20000 topographic data) could be
many dates or a range. Please note - in this sample all the
selections have been left for you to view. In a real metadata
file, only the applicable ones should be used.
- Data Quality Information
(desirable but, optional)
This section (along with 3, 4, 5,
and 6) is considered mandatory only if it applies to your
data. The items in
CAPS AND
BOLD are
those the service GIS coordinators feel are important. The
items in this section in
bold are
those items that need to be filled in both to comply with the
standard and to make the FGDC clearinghouse software work
properly if the section in question is used.
Basic notes on data quality are very
useful. Most GIS staff have wrestled with data that did not
document what the attribute codes stood for, or files that did
not match at the edges. Any items you can complete here would be
useful.
- Spatial Data Organization
Information (desirable but, optional)
This section (along with 2, 4, 5, and 6)
is considered mandatory only if it applies to your data. The
items in CAPS
AND BOLD are
those the service GIS coordinators feel are important. The items
in this section in
bold are
those items that need to be filled in both to comply with the
standard and to make the FGDC clearinghouse software work
properly if the section in question is used.
This section can be very simple or very detailed. At a minimum
we would like to know if the data is point, vector, raster, or
some non-referenced data set! If you wish to go beyond that
point, the type of file directs which other fields you need.
- Spatial Reference Information
(desirable but, optional)
This section (along with 2, 3, 5, and 6)
is considered mandatory only if it applies to your data. The
items in CAPS
AND BOLD are
those the service GIS coordinators feel are important. The items
in this section in
bold are
those items that need to be filled in both to comply with the
standard and to make the FGDC clearinghouse software work
properly if the section in question is used.
Section 4 is guaranteed to give a majority of GIS users in
Manitoba Conservation either heartburn or a headache the first
time they read it. It goes into very technical detail, including
many items geographers may understand but most biologists have
never heard of. There are, however, some important basic items
here that should be documented. This is another mandatory if
applicable section, but certainly some of it SHOULD be
applicable!
Section 4 offers some choices depending on
your data. You may have geographic data (lat/long - section
4.1), planar data (section 4.2 - includes UTM and state plane
data), or local (table inches - some autocad type data). It will
not be all of these at once. Your data entry is simplified, but
the potential number of choices make the documentation look
forbidding. In addition to the horizontal coordinates, some data
needs the vertical coordinates. It may be river depth data,
perhaps DEM or other topographic data - vertical coordinates are
not listed here, but are in the base template if needed.
- Entity and Attribute Information
(desirable but, optional)
This section (along with 2, 3, 4, and 6)
is considered mandatory only if it applies to your data. The
items in CAPS
AND BOLD are
those the service GIS coordinators feel are important. The items
in this section in
bold are
those items that need to be filled in both to comply with the
standard and to make the FGDC clearinghouse software work
properly if the section in question is used.
For this section an office would probably use either 5.1 or 5.2,
depending on the amount of detail needed to describe the data,
or the amount of detail available. If an office chose to give an
overview description (5.2 ) of a vegetation layer, for example,
they could also cite a reference such as the GAP or TNC
vegetation classification standard to give the user further
details about the data. If they chose to use 5.1, they could
include all the details in the metadata. If the reference is
widely available, doing an overview and referencing other
documents is probably easier.
- Distribution Information
(desirable but, optional)
This section (along with 2, 3, 4, and 5)
is considered mandatory only if it applies to your data. The
items in CAPS
AND BOLD are
those the service GIS coordinators feel are important. The items
in this section in
bold are
those items that need to be filled in both to comply with the
standard and to make the FGDC clearinghouse software work
properly if the section in question is used.
Basically, how can someone get the data from you? Is in
"on-line"? Who do they contact? Your own circumstances
will dictate what gets filled in here. If the distributor is the
same as the contact person in Section 7, it could be left out
here. Often, however, they will be different staff or offices.
(Hint: if you want to enter the contact information here and
sections 1 or 7, and the information is very similar, you can
cut and paste in Windows. Just be sure to copy the headings and
data for the section.)
- Metadata Reference Information
(required)
Who documented the data, when and using
what type of documentation? This can be important if the data
was documented 10 years after it was created versus as it was
created. The quality of the metadata will vary.
Bold and italicized sections
here are mandatory for the FGDC.
The following pages contain an outline
of the basic data elements, with short "cheat sheet"
type notes and sample data. These should be used only as
guidelines.
For additional information regarding this
document, contact
mailto:ldonnelly@gov.mb.ca
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Datum
Standard
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Definition of Provincial Reference Systems in Manitoba
NAD83(CSRS98)
will become the standard for
new work.
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NAD83:
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North
American Datum 1983. The horizontal control datum for
Canada, U.S.A., Denmark (Greenland), Mexico and Central
America. Based on the geocentric reference ellipsoid
Geodetic Reference System 1980 (GRS80).
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NAD83(CSRS98):
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North
American Datum 1983 Canadian Spatial Reference System. A new
realization of NAD83 derived from an adjustment of the
Canadian Base Network and high order GPS tied to the
Canadian Active Control System (CACS). Reference ellipsoid
is GRS80. Depending on accuracy requirements these
coordinates may not be compatible with previous NAD83 values
(June'90, NMIP94).
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NAD27:
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North
American Datum 1927. A non-geocentric horizontal control
datum for the U.S., Canada and Mexico defined by a
coordinate and azimuth with origin at Meades Ranch, on the
Clarke 1866 reference ellipsoid.
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CGVD28:
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Canadian
Geodetic Vertical Datum 1928, mean sea level (adopted public
vertical reference system.). The average height of the
surface of the sea for all stages of the tide, determined by
averaging height readings observed hourly over a minimum
period of 19 years.
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Related
Terms
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Datum:
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A
point, line, surface or set of quantities used as a
reference upon which measurements are based.
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Ellipsoid:
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A
smooth mathematical surface which resembles a compressed
sphere and is used to represent the earth's surface.
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Geocentric:
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Relating
to, measured from, or with respect to the centre of mass of
the earth.
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