INFOMAR Seabed Survey Bathymetry (Multi-beam & LiDAR)

Category: Science
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This data shows the depth of the seabed around Ireland. The data was collected in 1996 and between 2000 and 2022.

Bathymetry is the measurement of how deep is the sea. Bathymetry is the study of the shape and features of the seabed. The name comes from Greek words meaning "deep" and “measure".

Bathymetry is collected on board boats working at sea and airplanes over land and coastline. The boats use special equipment called a multibeam echosounder. A multibeam echosounder is a type of sonar that is used to map the seabed. Sound waves are emitted in a fan shape beneath the boat. The amount of time it takes for the sound waves to bounce off the bottom of the sea and return to a receiver is used to determine water depth.

LiDAR (Light Detection and Ranging) is another way to map the seabed, using airplanes. Two laser light beams are emitted from a sensor on-board an airplane. The red beam reaches the water surface and bounces back; while the green beam penetrates the water hits the seabed and bounces back. The difference in time between the two beams returning allows the water depth to be calculated. LiDAR is only suitable for shallow waters (up to 30m depth).

The data are collected as points in XYZ format. X and Y coordinates and Z (depth). The boat travels up and down the water in a series of lines (trackline). An XYZ file is created for each line and contains thousands of points. The line files are merged together and converted into gridded data to create a Digital Terrain Model of the seabed.

Colours are also used to show depth ranges.

These are raster datasets. Raster data stores information in a cell-based manner and consists of a matrix of cells (or pixels) organised into rows and columns. The format of the raster is a grid. The grid cell size varies. The highest resolution is 10m by 10m. This means that each cell (pixel) represents an area on the seabed of 10 metres squared. Each cell has a depth value which is the average depth of all the points located within that cell.

This data shows areas that have been surveyed. There are plans to fill in the missing areas between 2020 and 2026. The deeper offshore waters were mapped as part of the Irish National Seabed Survey (INSS) between 1999 and 2005. INtegrated Mapping FOr the Sustainable Development of Ireland's MArine Resource (INFOMAR) is mapping the inshore areas. (2006 - 2026).

Data Resources (8)

WMS
WMS 10M inshore
REST
ESRI Image Service 10M Inshore
REST
ESRI Image Service 25M
REST
ESRI Image Service 100M
HTML
Data Viewer
HTML
Data Download

Data Resource Preview - WMS 10M inshore

Theme Science
Date released 2015-02-01
Date updated 2021-05-17
Dataset conforms to these standards The INSPIRE Directive or INSPIRE lays down a general framework for a Spatial Data Infrastructure (SDI) for the purposes of European Community environmental policies and policies or activities which may have an impact on the environment.
Rights notes ['Creative Commons Attribution 4.0 International (CC BY 4.0) licence', 'https://creativecommons.org/licenses/by/4.0/\n\nRights (can)\nShare- copy and redistribute the data in any medium or format\nAdapt- remix, transform, and build upon the material for any purpose, even commercially\n\nRequirements (must)\nAttribution- Give appropriate credit, provide a link to the licence, and indicate if changes were made. Do so in any reasonable manner, but not in any way that suggests the license endorses you or your use\nNo additional restrictions - may not apply legal terms or technological measures that legally restrict others from doing anything the license permits\n\nUnder the CC-BY Licence, users must acknowledge the source of the Information in their product or application.\n\nPlease use this specific attribution statement: "Contains Irish Public Sector Data (Geological Survey Ireland & Marine Institute) licensed under a Creative Commons Attribution 4.0 International (CC BY 4.0) licence".', 'license']
Update frequency Annual
Language English
Landing page https://gsi.geodata.gov.ie/portal/apps/webappviewer/index.html?id=85b8ecf8832e40cca6d923aa0688f08e
Geographic coverage in GeoJSON format {"type":"Polygon","coordinates":[[[-20.1, 51.5],[-20.1, 57.1], [-5.1, 57.1], [-5.1, 51.5], [-20.1, 51.5]]]}
Spatial Reference Systems (SRS) WGS 84 (EPSG:4326)
Vertical Extent {"verticalDomainName": "sea level", "minVerticalExtent": "-4813.705078125", "maxVerticalExtent": "62.41544795781374"}
Provenance information 1. Multibeam echosounder data processed using CARIS HIPS and SIPS by hydrographic processing team. 2. Backscatter grid exported from CARIS in WGS84 Latitude Longitude units based on strength of acoustic signal data processing. 3. Source Backscatter grid from Survey Leg folder. 4. Add source Backscatter grid to ArcGIS Desktop application. 5. Reset default "grey" shade blend using symbology tools Stretch Type 'Minimum-Maximum' and invert this setting blending in with surrounding backscatter data. 6. Using “Data - Data Export” option export ASC GRID as 3 Band (output raster = use renderer) WGS84 LAT (ArcGIS raster dataset) image to appropriate vessel “Backscatter” File Geodatabase following standard backscatter product name conventions: a. Product name (e.g. BS) b. Survey Vessel leg identifier (e.g. CE20_02) c. Geographical name (e.g. Donegal, Kerry, CelticSea) d. Image pixel resolution (e.g. 2m, 5m, 10m) e. Image Coordinate Reference System (e.g. WGS84) f. Raster Bands (e.g. 3B) g. CARIS backscatter processing mode (e.g. 2) 7. Open ArcGIS File Geodatabase backscatter image in ArcGIS Pro to ensure final quality control check against core Backscatter dataset. 8. Load each individual grid using ArcGIS Model Builder Mosaic to New Raster and Build Pyramids toolsets.
Period of time covered (begin) 1996-01-01