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Map of the North Circumpolar Region

Canada is vast, boasting a diverse range of distinct regions and landscapes. Living in one of the northernmost and largest countries in the world, helps provide Canadians with a unique perspective on our country’s geography. To help showcase Canada’s dynamic Arctic landscape, Natural Resources Canada (NRCan) released an updated version of the North Circumpolar Map.

This unique bilingual map map is viewed from a different angle then most maps, using the azimuthal equidistant projection with the geographic North Pole serving as the central point of the map. We encourage all Canadians to take advantage of this free high resolution map available for download from NRCAN and help promote a unique perspective of our prodigious nation.

New Canadian Geodetic Vertical Datum

Canadian Geodetic Vertical Datum Diagram

New Canadian Geodetic Vertical Datum

Geodetic reference systems stem from the need to have a consistent integrated reference surface for data analysis in applications such as surveying, cartography, navigation, remote sensing and mineral exploration. National Resources Canada (NRCan) maintains the Canadian Spatial Reference System (CSRS), through the use of the North American Datum of 1983 (NAD83CSRS) and has been an adopted standard in Canada.

NRCan has recently made a new Canadian Geodetic Vertical Datum available: CGVD2013, which is now the new reference standard for Canadian reference heights. This new height reference system replaces the Canadian Geodetic Vertical Datum of 1928 (CGVD28), which was adopted officially by an Order in Council in 1935 and has been used by organizations and individuals coast to coast for the past few decades.

“CGVD2013 is defined by the equipotential surface ( W0=62636856,0m2s?2 ), which represents by convention the coastal mean sea level for North America. This definition comes from an agreement between the United States of America and Canada. This new vertical datum is realized by the geoid model CGG2013, which provides the separation between the GRS80 ellipsoid and the above described surface in NAD83(CSRS) reference frame, making it compatible with Global Navigation Satellite Systems (GNSS) such as GPS.

The height of the benchmarks is also available in CGVD2013. These heights come from a readjustment of the entire federal first-order levelling network. However, CGVD2013 heights obtained from GNSS and geoid model CGG2013 prevail over the published elevations because NRCan cannot confirm the accuracy of the heights and stability of the benchmarks derived from the aging levelling network.

NRCan is continuing the publication of heights at benchmarks in CGVD28 and hybrid geoid model HTv2.0 to assure a smooth and gradual transition period to the new height reference system.”

CGG2013 is the Canadian gravimetric geoid model of 2013 realizing the Canadian Geodetic Vertical Datum of 2013 (CGVD2013). The model comes with an accuracy model for the geoid heights. CGG2013 can be downloaded through the NRCan Geoid Models page. (User account required, but it is free to signup for one)

[image source: nrcan.gc.ca]


Converting between UTM, MTM and LAT/LONG

Geographic coordinate systems enable us to spatially locate features on the Earth using specified set of two dimensional numbers. The coordinates of each feature represent the horizontal position (and sometimes vertical position when elevation is available) of it and one of the most commonly used coordinates is Geographic with values of latitude, longitude. However many different coordinate systems can be used to map the same area depending on various factors such as map extent, scale, end user etc. Therefore we often find in Geomatics that we can have data from different coordinate systems that we need to use together spatially in one reference system.

Most of us have run into times when we have features that have defined coordinates of one system that we need to use with a different one. (E.g. your map is in UTM (Universal Transverse Mercator) but you have been given GPS points in Lat/Long).

If you ever find yourself in need of quickly getting values converted from Geographic to UTM / MTM (Modified Traverse Mercator) or UTM / MTM to Geographic then here is a a free online converter tool that we use provided by Canadian Spatial Reference System.

New and Improved GeoGratis Website

GeoGratis free Canadian geospatial data web portal

Natural Resources Canada (NRCan) has recently launched a new update to the already innovative GeoGratis website (Note: although it has gone live it is still in beta mode).  GeoGratis is a web portal that provides access to a wide collection of Canadian geospatial data, maps, images, and publications at no cost and without restrictions.

All data accessed via GeoGratis comes with an Unrestricted Use Licence Agreement that grants users a non-exclusive, royalty-free right and licence to exercise all intellectual property rights in the data including the right to use, incorporate, sub-license, modify, further develop, and distribute the data. The various downloadable geospatial data, maps, images, and publications in several different popular formats such as geopdf, geotiff, pdf, shape file and tiff.

GeoGratis Canadian Geospatial Data Portal

Improvements to the new site made go much deeper then just minor cosmetic changes. GeoGratis Website  is now easier to use and allows access to better search tools where one can now view and download all available geospatial data sets consolidated into the same web site.

The new Platform also now better supports developers that want to create unique and innovative mapping applications with Canadian data, images and documents using one of the three available GeoGratis Application Programming Interfaces (API’s). These include the GeoGratis API, the GeoLocation API and also an updated Canada base web map service (WMS) that now also includes Canadian transportation data (Canada Base Map for Transportation – CBM-T).

NRCan feels that the new GeoGratis service is compatible with OpenGIS® Consortium (OGC), innovative and cutting-edge, and will provide a better one stop site for people to obtain Canadian geospatial data, maps, images and publications.

The New GeoGratis Website: An Innovative Geospatial Platform for all Canadians; consolidates several location-based services including The Canadian Geographical Names Database (CGNDB), Atlas Gazetteer, Postal Codes and National Topographic System (NTS) Map search. The CGNDB manages names records for populated places and physical features across Canada. Users can search by geographic location using the map of Canada, name, physical feature, subject, NTS number or product title.

GeoGratis - Search geospatial gis data results

NRCan has been listening to what the geomatics community has been asking for all along. And as a result have taken what was already a pretty good service that offered free data and information and consolidated it together, cleaned it up and then added some more tools as well.

Therefore one should only expect that with all this royalty-free geospatial data and API tools now available that we should start to see more Canadian Cities and Municipalities start to offer web mapping sites and geographic information for their citizens.

Take a look at the new and improved GeoGratis Website for yourself using either the new search interface or simply browse through the extensive directory listing of hundreds of different maps, imagery and geospatial data sets to discover what the Federal Government of Canada has to offer the geomatics community.