Wellington - Kapiti Coast LiDAR 1m DSM (2021)
This layer contains the DSM for LiDAR data in the Kapiti District and includes Kapiti coast, Paraparaumu, Paekākāriki, Ōtaki and the surrounding area captured in 2021.
- The DEM is available as layer [Wellington - Kapiti Coast LiDAR 1m DEM (2021)]( https://data.linz.govt.nz/layer/106990 )
- The index tiles are available as layer [Wellington - Kapiti Coast LiDAR Index Tiles (2021)]( https://data.linz.govt.nz/layer/10698 3)
- The LAS point cloud and vendor project reports are available from [OpenTopography]( https://portal.opentopography.org/datasets?loc=New%20Zealand )
LiDAR was captured for the Kapiti Coast District Council by AAM Ltd from 13 March to 15 March 2021. The dataset was generated by AAM and their subcontractors. Data management and distribution is by Toitū Te Whenua Land Information New Zealand.
Data comprises:
- DEM: tif or asc tiles in NZTM2000 projection, tiledinto a 1:1,000 tile layout
- DSM: tif or asc tiles in NZTM2000 projection, tiled into a 1:1,000 tile layout
- Point cloud: las tiles in NZTM2000 projection, tiled into a 1:1,000 tile layout
Pulse density specification is at a minimum of 8 pulses/square metre.
Vertical Accuracy Specification is +/- 0.1m (95%)
Horizontal Accuracy Specification is +/- 0.5m (95%)
Vertical datum is NZVD2016.
Simple
Identification info
- Date (Creation)
- 2021-03-13
- Status
- Completed
- Point of contact
-
Role Organisation Electronic mail address Point of contact Toitū Te Whenua Land Information New Zealand
- Spatial representation type
- Grid
Spatial resolution
Equivalent scale
- Denominator
- 1000
- Topic category
-
- Elevation
Extent
- Geographic identifier
-
nzl
- Title
-
ANZMet Lite Country codelist
- Date (Publication)
- 2009-03-31
- Edition
-
Version 1.0
- Edition date
- 2009-03-31
- Citation identifier
- http://asdd.ga.gov.au/asdd/profileinfo/anzlic-country.xml#Country
- Cited responsible party
-
Role Organisation Electronic mail address Custodian ANZLIC the Spatial Information Council
Extent
))
- Maintenance and update frequency
- Not planned
Resource format
- Title
-
*.xml
- Date
- Edition
-
Unknown
- ANZLIC Jurisdictions
-
-
New Zealand
-
Resource constraints
- Classification
- Unclassified
Resource constraints
- Use limitation
-
Copyright in this work is owned by Kapiti Coast District Council
© Kapiti Coast District Council
- Use constraints
- Copyright
Resource constraints
- Use limitation
-
Released by Toitū Te Whenua Land Information New Zealand under Creative Commons Attribution 4.0 New Zealand (CC BY 4.0) with:
Following Attribution:
"Sourced from the LINZ Data Service and licensed by Kapiti Coast District Council, for re-use under CC BY 4.0."
For details see: https://www.linz.govt.nz/data/licensing-and-using-data/attributing-elevation-or-aerial-imagery-data
- Use constraints
- License
- Language
- English
- Character encoding
- UTF8
Resource lineage
- Statement
-
Data Acquisition:
Airborne Laser Scanner (ALS) data was acquired from a fixed wing aircraft from 13 March 2021 to 15 March 2021, using AAM's Optech Galaxy Prime 473 LiDAR system.
Survey Specification:
- Scanner: Optech Galaxy Prime 473
- Flying height: 805 m AGL
- Scan angle: 22.5 degrees
- Pulse rate: 450 kHz
- Swath overlap: 60%
- Swath points per M^2: 8.26 with overlap flag to achieve 16 pts per sq m.
Data Processing:
Laser strikes were classified into ground and non-ground points using a single algorithm across the project area. Manual checking and editing of the data classification further improved the quality of the ground point classification.
AAM uses proprietary ground classification routines to provide the initial automated ground / non-ground classification and generate the initial ground surface. The classification is then manually edited to improve the ground classification to ICSM level 2 standard. Following this process, further automated techniques are used to classify the other classes shown above to ICSM level 1 standard.
RTX processing was used to calculate the GPS trajectory solution. Trimble CenterPoint® RTX™ is a proprietary GPS, GLONASS, BeiDou, and QZSS enabled technology that provides high accuracy GNSS positioning worldwide without the use of traditional local base stations or a VRS network. By combining real-time data from a global reference station infrastructure with innovative positioning and compression algorithms, Trimble RTX technology computes centimeter-level positions based on satellite orbit and clock information. Ground surveyed test point sites were acquired by WSP, these allowed an assessment of the accuracy of the ALS point cloud data.
Ground data in this volume has been compared to test points obtained by field survey and assumed to be error-free. The test points were located on open clear ground. Comparison of the field test points with elevations interpolated from measured data, after removing the mean offset yielded the following accuracy assessment:
- Test point sites: 5
- No. Points: 221- Mean Difference: 0.00
- Std Deviation (m): 0.01
- RMS (m): 0.01
All product deliverables supplied in terms of NZTM map projection and NZVD2016 vertical datum.
Classification of the point cloud followed the classifications scheme below:
1- Unclassified
2 - Ground
3 - Low Vegetation
4 - Medium Vegetation
5 - High Vegetation
6 - Buildings
7 - Low Noise
9 - Water
17 - Bridge deck
18 - High Noise
The classification was undertaken in accord with the project specification (Toitū Te Whenua Land Information New Zealand, 2020, PGF Version: New Zealand National Aerial LiDAR Base Specification, January 2020).
Elevation Grids were derived using the LAStools las2dem command. This tool reads LIDAR points from the LAS/LAZ format (or some ASCII formats) and triangulates them temporarily into a TIN with a user defined interpolation distance. LAStools then applies a TIN to raster conversion to create the 1m DEM raster dataset.
High and low noise classes (7 and 18) have been removed from the point cloud.
Lakes and large rivers were hydroflattened in the Bare Earth Digital Elevation Model.
The deliverables to LINZ were:
1m gridded bare earth digital elevation model (DEM)
1m gridded digital surface model (DSM)
Classified point cloud
- Hierarchy level
- Dataset
- Other
-
dataset
Reference System Information
- Reference system identifier
- 2193
Metadata constraints
- Use limitation
-
Copyright of this work is owned by Toitū Te Whenua Land Information New Zealand
© LINZ
- Use constraints
- Copyright
Metadata constraints
- Use limitation
-
Released by Toitū Te Whenua Land Information New Zealand under Creative Commons Attribution 4.0 International (CC BY 4.0) with:
Following Attribution:
"Sourced from the LINZ Data Service and licensed for reuse under CC BY 4.0"
For details see https://www.linz.govt.nz/data/licensing-and-using-data/attributing-linz-data
- Use constraints
- License
Metadata
- Metadata identifier
- c0dacc5f-5816-4d41-08de-931a1065a518
- Language
- English
- Character encoding
- UTF8
- Contact
-
Role Organisation Electronic mail address Point of contact Toitū Te Whenua Land Information New Zealand
Type of resource
- Resource type
- Dataset
- Name
-
dataset
- Date info (Revision)
- 2022-01-21
Metadata standard
- Title
-
ANZLIC Metadata Profile: An Australian/New Zealand Profile of AS/NZS ISO 19115:2005, Geographic information - Metadata
- Edition
-
1.1