The Dunedin 1958 to NZVD2016 Conversion Raster provides users with a two arc-minute (approximately 3.6 kilometres) raster image of the conversion of normal-orthometric heights from the Dunedin 1958 local vertical datum to the New Zealand Vertical Datum 2016 (NZVD2016). The conversion value is represented by the attribute “O”, in metres. This conversion and NZVD2016 are formally defined in the LINZ standard [LINZS25009](http://www.linz.govt.nz/regulatory/25009). The height conversion grid models the difference between the Dunedin 1958 vertical datum and NZVD2016 using the LINZ GPS-levelling marks. From the GPS-levelling marks the expected accuracy is better than 2 centimetres (95% Confidence interval). More information on converting heights between vertical datums can be found [on the LINZ website](http://www.linz.govt.nz/data/geodetic-services/coordinate-conversion/converting-between-nzvd2016-nzgd2000-and-local-vertical-datums).

The Gisborne 1926 to NZVD2016 Conversion Raster provides users with a two arc-minute (approximately 3.6 kilometres) raster image of the conversion of normal-orthometric heights from the Gisborne 1926 local vertical datum to the New Zealand Vertical Datum 2016 (NZVD2016). The conversion value is represented by the attribute “O”, in metres. This conversion and NZVD2016 are formally defined in the LINZ standard [LINZS25009](http://www.linz.govt.nz/regulatory/25009). The height conversion grid models the difference between the Gisborne 1926 vertical datum and NZVD2016 using the LINZ GPS-levelling marks. From the GPS-levelling marks the expected accuracy is better than 2 centimetres (95% Confidence interval). More information on converting heights between vertical datums can be found [on the LINZ website](http://www.linz.govt.nz/data/geodetic-services/coordinate-conversion/converting-between-nzvd2016-nzgd2000-and-local-vertical-datums).

Geographic locations at which daily tide predictions are available. Official Tide Prediction data is available on the LINZ website at http://www.linz.govt.nz/hydro/tidal-info/tide-tables. THIS DATA DOES NOT REPLACE OFFICIAL TIDE PREDICTIONS AND MUST NOT BE USED FOR NAVIGATION. Tide Prediciton information has been prepared by LINZ from analysis of sea level observations supplied by port companies, regional and district councils and the National Institute of Water and Atmospheric Research Limited (NIWA).

**Note:** This layer has been provided to enable potential users to identify the coverage of photography for Mainland NZ flown on behalf of the Crown between 1936 and 2005. The layer shows the extent of each photograph taken. The [NZ Aerial Survey Footprints, Mainland NZ, (1936-2005) polygons layer](https://data.linz.govt.nz/layer/1000-nz-aerial-survey-footprints-mainland-nz-1936-2005-polygons) shows the extent of each survey undertaken, and the [Digitised Historic Aerial Surveys Available for Download (1936-2005)](https://data.linz.govt.nz/layer/2418) layer shows the extents of the surveys digitised and released by LINZ under open license. See [http://www.linz.govt.nz/about-linz/what-were-doing/projects/crown-historic-aerial-photo-archive-scanning-project](http://www.linz.govt.nz/about-linz/what-were-doing/projects/crown-historic-aerial-photo-archive-scanning-project) for direction on how to access the digitised photos. The photos are not downloadable from the LINZ Data Service. The Crown Aerial Film Negative Collection is managed for LINZ by Opus International.You can are order images from the Collection from Opus International in a number of formats, including: - contact prints - enlargements - digital files - precision scans for photogrammetric production - orthophotos You will need to tell Opus International the survey, run and photo number (values in the ‘SURVEY’ 'RUN' and 'PHOTO_NO' attributes) covering your area of interest. Opus International will be able to provide information about the cost of providing images in the various formats. Contact them at: photosales@opus.co.nz or 0800 680 690 There are also a large number of images which previously belonged to New Zealand Aerial Mapping and which are now are available for public use. The extents of these may be added to the LDS in future. You can order these images by contacting Opus International.

The Nelson 1955 to NZVD2016 Conversion Raster provides users with a two arc-minute (approximately 3.6 kilometres) raster image of the conversion of normal-orthometric heights from the Nelson 1955 local vertical datum to the New Zealand Vertical Datum 2016 (NZVD2016). The conversion value is represented by the attribute “O”, in metres. This conversion and NZVD2016 are formally defined in the LINZ standard [LINZS25009](http://www.linz.govt.nz/regulatory/25009). The height conversion grid models the difference between the Nelson 1955 vertical datum and NZVD2016 using the LINZ GPS-levelling marks. From the GPS-levelling marks the expected accuracy is better than 2 centimetres (95% Confidence interval). More information on converting heights between vertical datums can be found [on the LINZ website](http://www.linz.govt.nz/data/geodetic-services/coordinate-conversion/converting-between-nzvd2016-nzgd2000-and-local-vertical-datums).

This index enables you to identify the locations of current and historic sea level stations around New Zealand, on offshore islands (including Raoul Island, Chatham Islands and the sub-Antarctic islands), several South West Pacific islands and the Ross Dependency (Antarctica). The attributes attached to each location will enable you to look up tidal levels, obtain relationships between tidal and land-based height datums, access tide predictions on LINZ’s website and find out how much sea level data LINZ has in its archive. See the LINZ website for official [tide predictions](https://www.linz.govt.nz/sea/tides/tide-predictions). View the attached data dictionary for detailed information about the attributes of this dataset. **Accessing sea level data** The data that is used to calculate tide predictions is also available. You can access publically available sea level data where a URL is provided in the data_link column. For other locations, requests for sea level data should be sent to customersupport@linz.govt.nz with “Sea Level Data” in the subject line. Requests must, as a minimum, specify the location and time period that the data is required for. Publically funded data can be released to the public under a Creative Commons licence for reuse. The provision of sea level data funded by third parties may be subject to some delay, as LINZ must obtain permission from the data owner. The owner may also attach conditions to the release of their data.

The Moturiki 1953 to NZVD2016 Conversion Raster provides users with a two arc-minute (approximately 3.6 kilometres) raster image of the conversion of normal-orthometric heights from the Moturiki 1953 local vertical datum to the New Zealand Vertical Datum 2016 (NZVD2016). The conversion value is represented by the attribute “O”, in metres. This conversion and NZVD2016 are formally defined in the LINZ standard [LINZS25009](http://www.linz.govt.nz/regulatory/25009). The height conversion grid models the difference between the Moturiki 1953 vertical datum and NZVD2016 using the LINZ GPS-levelling marks. From the GPS-levelling marks the expected accuracy is better than 2 centimetres (95% Confidence interval). More information on converting heights between vertical datums can be found [on the LINZ website](http://www.linz.govt.nz/data/geodetic-services/coordinate-conversion/converting-between-nzvd2016-nzgd2000-and-local-vertical-datums).

The Stewart Island 1977 to NZVD2016 Conversion Raster provides users with a two arc-minute (approximately 3.6 kilometres) raster image of the conversion of normal-orthometric heights from the Stewart Island 1977 local vertical datum to the New Zealand Vertical Datum 2016 (NZVD2016). The conversion value is represented by the attribute “O”, in metres. This conversion and NZVD2016 are formally defined in the LINZ standard [LINZS25009](http://www.linz.govt.nz/regulatory/25009). The height conversion grid models the difference between the Stewart Island 1977 vertical datum and NZVD2016 using the LINZ GPS-levelling marks. From the GPS-levelling marks the expected accuracy is better than 2 centimetres (95% Confidence interval). More information on converting heights between vertical datums can be found [on the LINZ website](http://www.linz.govt.nz/data/geodetic-services/coordinate-conversion/converting-between-nzvd2016-nzgd2000-and-local-vertical-datums).

The Nelson 1955 to NZVD2016 Conversion Raster provides users with a two arc-minute (approximately 3.6 kilometres) raster image of the conversion of normal-orthometric heights from the Nelson 1955 local vertical datum to the New Zealand Vertical Datum 2016 (NZVD2016). The conversion value is represented by the attribute “O”, in metres. This conversion and NZVD2016 are formally defined in the LINZ standard [LINZS25009](http://www.linz.govt.nz/regulatory/25009). The height conversion grid models the difference between the Nelson 1955 vertical datum and NZVD2016 using the LINZ GPS-levelling marks. From the GPS-levelling marks the expected accuracy is better than 2 centimetres (95% Confidence interval). More information on converting heights between vertical datums can be found [on the LINZ website](http://www.linz.govt.nz/data/geodetic-services/coordinate-conversion/converting-between-nzvd2016-nzgd2000-and-local-vertical-datums).

In June 2014 the Authoritative Streets and Places (ASP) database was decommissioned, and at the same time a new Landonline SUFI was created for each unique road name / locality combination in the Landonline Road Name table. Prior to this change the Landonline Road Name table held the ASP Street SUFI in its Locality field, and a join was made between these two tables in order to populate the Landonline Locality field with the ASP locality name prior to release on the LDS. Following this change the Locality field in the Landonline Road Name table was updated to show the locality name as held in the ASP Street table. This table shows the mapping between the new Landonline Road Name SUFI and the old ASP Street SUFI. The Topo50 Road Centrelines data previously included the name_id attribute (equivalent to asp_sufi), which has now been changed to the new rna_sufi attribute (equivalent to landonline_sufi).