Land Information New Zealand Research Articles

Mapping New Zealand 2025 – A National Perspective

Mapping New Zealand 2025 – A National Perspective

Enhancing Location-Related Hydrogeological Knowledge

We analyzed the corpus of three geoscientific journals to investigate if there are enough locational references in research articles to apply a geographical search method, such as the example of New Zealand. Based on all available abstracts and all freely available papers of the “New Zealand Journal of Geology and Geophysics”, the “New Zealand Journal of Marine and Freshwater Research”, and the “Journal of Hydrology, New Zealand”, we searched title, abstracts, and full texts for place name occurrences that match records from the official Land Information New Zealand (LINZ) gazetteer. We generated ISO standard compliant metadata records for each article including the spatial references and made them available in a public catalogue service. This catalogue can be queried for articles based on authors, titles, keywords, topics, and spatial reference. We visualize the results in a map to show which area the research articles are about, and how much and how densely geographic space is described through these geoscientific research articles by mapping mentioned place names by their geographic locations. We outlined the methodology and technical framework for the geo-referencing of the journal articles and the platform design for this knowledge inventory. The results indicate that the use of well-crafted abstracts for journal articles with carefully chosen place names of relevance for the article provides a guideline for geographically referencing unstructured information like journal articles and reports in order to make such resources discoverable through geographical queries. Lastly, this approach can actively support integrated holistic assessment of water resources and support decision making.

An investigation into the performance of real-time GPS+GLONASS Precise Point Positioning (PPP) in New Zealand

Abstract This paper presents an investigation into the performance of real-time Global Navigation Satellite Systems (GNSS) Precise Point Positioning (PPP) in New Zealand. The motivation of the research is to evaluate the feasibility of using PPP technique and a satellite based augmentation system such as the Japanese Quasi-Zenith Satellite System (QZSS) to deliver a real-time precise positioning solution in support of a nation-wide high accuracy GNSS positioning coverage in New Zealand. Two IGS real-time correction streams are evaluated alongside with the PPP correction messages transmitted by the QZSS satellite known as MDC1. MDC1 corrections stream is generated by Japan Aerospace Exploration Agency (JAXA) using the Multi-GNSS Advanced Demonstration tool for Orbit and Clock Analysis (MADOCA) software and are currently transmitted in test mode by the QZSS satellite. The IGS real-time streams are the CLK9B real-time corrections stream generated by the French Centre National D’études Spatiales (CNES) using the PPP-Wizard software, and the CLK81 real-time corrections stream produced by GMV using their MagicGNSS software. GNSS data is collected from six New Zealand CORS stations operated by Land Information New Zealand (LINZ) over a one-week period in 2015. GPS and GLONASS measurements are processed in a real-time PPP mode using the satellite orbit and clock corrections from the real-time streams. The results show that positioning accuracies of 6 cm in horizontal component and 15 cm in vertical component can be achieved in real-time PPP. The real-time GPS+GLONASS PPP solution required 30 minutes to converge to within 10 cm horizontal positioning accuracy.

THE CURRENT STATUS OF MAPPING IN THE WORLD – SPOTLIGHT ON OCEANIA

A summary is presented of the results of questionnaires sent to mapping agencies in Oceania, covering Australia, New Zealand and the Pacific Island countries, to investigate the status of mapping in those countries. After World War II, the Australian Federal Government funded the initial small scale mapping of the whole country leading to increased percentages of map coverage of Australia. Mapping at larger scales is undertaken by the states and territories in Australia, including cadastral mapping. In New Zealand mapping is maintained by Land Information New Zealand (LINZ) at 1:50,000 scale and smaller with regular updating. The results of the questionnaires also demonstrate the extent of map coverage in six Pacific Islands, but there is little information available on the actual percent coverage. Overall there are estimated to be an increases in the percentages of coverage of most map scales in Oceania. However, there appear to be insufficient professionals in most Pacific Island countries to maintain the mapping programs. Given that many Pacific Island countries will be impacted by rising sea level in the future, better mapping of these countries is essential. The availability of modern technology especially satellite images, digital aerial photography and airborne lidar data should enable the Pacific Island countries to provide better map products in future, but this would depend on foreign aid on many occasions.

THE CURRENT STATUS OF MAPPING IN THE WORLD – SPOTLIGHT ON OCEANIA

Abstract. A summary is presented of the results of questionnaires sent to mapping agencies in Oceania, covering Australia, New Zealand and the Pacific Island countries, to investigate the status of mapping in those countries. After World War II, the Australian Federal Government funded the initial small scale mapping of the whole country leading to increased percentages of map coverage of Australia. Mapping at larger scales is undertaken by the states and territories in Australia, including cadastral mapping. In New Zealand mapping is maintained by Land Information New Zealand (LINZ) at 1:50,000 scale and smaller with regular updating. The results of the questionnaires also demonstrate the extent of map coverage in six Pacific Islands, but there is little information available on the actual percent coverage. Overall there are estimated to be an increases in the percentages of coverage of most map scales in Oceania. However, there appear to be insufficient professionals in most Pacific Island countries to maintain the mapping programs. Given that many Pacific Island countries will be impacted by rising sea level in the future, better mapping of these countries is essential. The availability of modern technology especially satellite images, digital aerial photography and airborne lidar data should enable the Pacific Island countries to provide better map products in future, but this would depend on foreign aid on many occasions.

Determining the dynamic draught for precise hydrographic surveying

In hydrographic surveying, high precision is needed for engineering applications such as the construction of tube tunnels placed to seabed and the navigational safety of ships for the under keel clearance (UKC) in shallow canals or waterways. Minimum measurement standards for hydrographic surveying are created by the International Hydrographic Organization (IHO) for safety of navigation. As well as IHO, the Swedish Maritime Administration (SMA), Land Information New Zealand (LINZ), and the United States Army Corps of Engineers (USACE) standards are used in surveys. At 40-m depth, the depth error budget must be less than 40cm, according to IHO standards. Allowable maximum error is only 22cm in SMA hydrographic survey standards. These standards can be achieved by minimizing the error sources. One of the errors in hydrographic surveying is the determination of the transducer draught. Usually a static draught is used in hydrographic surveying. In this paper, the dynamic draught of a survey vessel is determined using the RTK GNSS method for different speeds. Differences between the static and dynamic draught values are analyzed for precise hydrographic surveying. It is determined that the dynamic draught of the vessel should be used for achieving the international standards in precise surveying projects.

Evaluation of the NZGeoid05 using GPS levelling in rural and elevated locations, South Island, New Zealand

To facilitate day to day surveying and mapping activities, Land Information New Zealand (LINZ) has developed a regional quasigeoid (NZGeoid05) by enhancing a global geopotential model with satellite, terrestrial and sea gravity data over the continental shelf of New Zealand (NZ). The overall national precision of NZGeoid05 was estimated by LINZ to be ±0.08 m (1σ). Six regions, distributed throughout the South Island of NZ, have been used to provide further independent verification of the precision of the NZGeoid05 by determining the geometric geoid-ellipsoid separation. In each region, several benchmarks with first-order normal-orthometric heights were selected and ellipsoidal heights measured independently using geodetic position techniques. A comparison has also been made with the global geopotential model, EGM2008. For NZGeoid05, four of the six regions tested have a RMS fit better than ±0.05 m, while for the EGM2008 this is only achieved in two regions. The estimated geoid slopes for both the NZGeoid05 and EGM2008 models agree with the geometric data to better than 1 cm/km in five of the six regions tested.

Improving hydrographic information ‐ zones of confidence (ZOC) for New Zealand

In July 2004 HSA Systems Ltd (HSA) commenced an eighteen month project for Land Information New Zealand (LINZ) to assess and assign Zones of Confidence (ZOCs) to all hydrographic surveys incorporated within 138 hydrographie charts of New Zealand. The project required each hydrographie survey to be assessed in relation to the data quality aspects of the International Hydrographie Organisation (IHO) S‐57 Standard (IHO, 2000). This paper will describe the process by which HSA assessed in excess of 1,792 hydrographie survey fair sheets and allocated 1,465 ZOCs to survey areas.