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snippet: Knowing the depth of the sea and its shape is vital for creating nautical charts. Accurate charts allow sailors to safely travel the seas. The charts give water depths so sailors can avoid running aground. They also provide locations of dangers such as rocks, sand banks or shipwrecks which may be located in shallow water or have objects such as a ship mast standing upright. This data is used by the United Kingdom Hydrographic Office (UKHO) to update the nautical charts used in Irish Waters. Seabed maps are useful when building structures on the seabed such as offshore energy devices (wind, tide and wave), bridges and tunnels. The maps help to select the best site for the structure. Understanding the terrain of the seabed will help prevent any disasters or long term problems with a structure. This can be done by avoiding unsuitable seabed terrain or engineering a project to suit the type of seabed terrain it is to be built on. They are also useful for laying cables and pipelines on the seabed. They help find the best route to lay them and help spot any hazards like shipwrecks. The maps are important for marine research. They allow us to study how the ocean crust formed and how glaciers once moved over coastal areas. They also help us to model how ocean currents and tides flow around the coastline and predict which coastal areas may be affected by rising sea levels. The maps help us figure out where marine species live, feed, and breed. This is important for fisheries and conservation.
summary: Knowing the depth of the sea and its shape is vital for creating nautical charts. Accurate charts allow sailors to safely travel the seas. The charts give water depths so sailors can avoid running aground. They also provide locations of dangers such as rocks, sand banks or shipwrecks which may be located in shallow water or have objects such as a ship mast standing upright. This data is used by the United Kingdom Hydrographic Office (UKHO) to update the nautical charts used in Irish Waters. Seabed maps are useful when building structures on the seabed such as offshore energy devices (wind, tide and wave), bridges and tunnels. The maps help to select the best site for the structure. Understanding the terrain of the seabed will help prevent any disasters or long term problems with a structure. This can be done by avoiding unsuitable seabed terrain or engineering a project to suit the type of seabed terrain it is to be built on. They are also useful for laying cables and pipelines on the seabed. They help find the best route to lay them and help spot any hazards like shipwrecks. The maps are important for marine research. They allow us to study how the ocean crust formed and how glaciers once moved over coastal areas. They also help us to model how ocean currents and tides flow around the coastline and predict which coastal areas may be affected by rising sea levels. The maps help us figure out where marine species live, feed, and breed. This is important for fisheries and conservation.
extent: [[-7.8313814256006,54.9392626271695],[-5.97974382999701,55.4442425226]]
accessInformation: Joint Irish Bathymetric Survey Project (JIBS)
thumbnail: thumbnail/thumbnail.png
maxScale: 1.7976931348623157E308
typeKeywords: ["Data","Service","Map Service","ArcGIS Server"]
description: <DIV STYLE="text-align:Left;"><DIV><DIV><P STYLE="text-align:Justify;"><SPAN>Bathymetry is the measurement of how deep is the sea. Bathymetry is the study of the shape and features</SPAN><SPAN> (eg Shipwrecks)</SPAN><SPAN> of the seabed. The name comes from Greek words meaning "deep" and “measure". Backscatter is the measurement of how hard is the seabed is. </SPAN></P><P STYLE="text-align:Justify;"><SPAN>Bathymetry and backscatter data are collected on board boats working at sea. 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. The strength of the sound wave is used to determine how hard the bottom of the sea is. A strong sound wave indicates a hard surface (rocks, gravel), and a weak signal indicates a soft surface (silt, mud). The word backscatter comes from the fact that different bottom types “scatter” sound waves differently. </SPAN></P><P STYLE="text-align:Justify;"><SPAN>The data are collected as points in XYZ format. X and Y coordinates, Z (depth) and backscatter value. 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. </SPAN></P><P STYLE="text-align:Justify;"><SPAN>Shaded relief is a cartographic technique that gives the seabed a realistic (3D) look. Mountains, valleys, plateaus, and canyons can be seen in deeper waters. The maps don’t show the exact depth. Depths are exaggerated and a point light source (“the sun”) is used to create light and shadows which highlight the shape of the seabed. Colours are also used to show depth ranges</SPAN><SPAN>. </SPAN><SPAN>Yellows and greens </SPAN><SPAN>show the shallower areas and blues and</SPAN><SPAN> purple </SPAN><SPAN>show</SPAN><SPAN> the deepest waters</SPAN><SPAN>.</SPAN></P><P STYLE="text-align:Justify;margin:0 0 11 0;"><SPAN><SPAN>Using the equipment also allows predictions as to the type of material present on the seabed e.g. rocks, pebbles, sand, mud. To confirm this, sediment samples are taken from the seabed. This process is called ground-truthing or sampling.</SPAN></SPAN></P><P STYLE="text-align:Justify;margin:0 0 11 0;"><SPAN>Grab sampling is the most popular method of ground-truthing. There are three main types of grab used depending on the size of the vessel and the weather conditions; Day Grab, Shipek or Van Veen Grabs. The grabs take a sample of sediment from the surface layer of the seabed. The samples are then sent to a lab for analysis. </SPAN></P><P STYLE="text-align:Justify;margin:0 0 11 0;"><SPAN>The JIBS datasets include bathymetry, shaded relief, hillshade, backscatter, shipwrecks, seabed sediment samples, survey coverage, survey tracklines and INFOMAR Lidar coverage.</SPAN></P><P STYLE="margin:0 0 11 0;"><SPAN>The dataset</SPAN><SPAN>s</SPAN><SPAN> w</SPAN><SPAN>ere</SPAN><SPAN> mapped as part of the Joint Irish Bathymetric Survey Project (JIBS). The Maritime and Coastguard Agency was the Project leader, approved under the INTERREG IIIA Programme, with the Marine Institute of Ireland as project partner. The objective of the JIBS Project was to promote joint action to survey the seabed in such a way as to satisfy the needs of many organisations. The JIBS project commenced on 10 April 2007 and was completed in June 2008. </SPAN></P></DIV></DIV></DIV>
licenseInfo: <DIV STYLE="text-align:Left;"><DIV><DIV><P STYLE="text-align:Justify;"><SPAN>Data that is produced directly by the Geological Survey Ireland (GSI) and the Marine Institute (MI) is free for use under the conditions of Creative Commons Attribution 4.0 International license. </SPAN></P><P STYLE="text-align:Justify;"><A href="https://creativecommons.org:443/licenses/by/4.0/" STYLE="text-decoration:underline;"><SPAN>https://creativecommons.org/licenses/by/4.0/</SPAN></A></P><P STYLE="text-align:Justify;"><A href="https://creativecommons.org:443/licenses/by/4.0/legalcode" STYLE="text-decoration:underline;"><SPAN>https://creativecommons.org/licenses/by/4.0/legalcode</SPAN></A></P><P STYLE="text-align:Justify;"><SPAN>Under the CC-BY Licence, users must acknowledge the source of the Information in their product or application. </SPAN></P></DIV></DIV></DIV>
catalogPath:
title: IE_GSI_MI_JIBS_Joint_Irish_Bathymetric_Survey_Inshore_IE_WGS84
type: Map Service
url:
tags: ["Ireland","IE/GSI","IE/MI","Geology","Marine Geology","seabed","seafloor","INFOMAR","Irish National Seabed Survey","Geological Survey Ireland","Marine Institute","JIBS","Maritime and Coastguard Agency","Elevation","bathymetry","Bathymetry and Elevation","water depth","backscatter","shaded relief","hillshade","shipwrecks","sediment","samples","survey","coverage","tracklines","lidar"]
culture: en-IE
name: IE_GSI_MI_JIBS_Joint_Irish_Bathymetric_Survey_Inshore_IE_WGS84
guid: 89148819-5AF0-4CCD-98FD-C4136F48A04B
minScale: 0
spatialReference: GCS_WGS_1984