{ "currentVersion": 10.81, "cimVersion": "2.6.0", "id": 8, "name": "Bathymetry Hillshade 4m", "type": "Raster Layer", "description": "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 \u201cmeasure\". Backscatter is the measurement of how hard is the seabed is. 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. 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. This is a raster dataset. 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 an image (GeoTIFF). The image cell size is 4m by 4m. This means that each cell (pixel) represents an area on the seabed of 4 metres squared. The map is coloured using grey shades. The dataset was 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. ", "geometryType": null, "copyrightText": "Joint Irish Bathymetric Survey Project (JIBS)", "parentLayer": null, "subLayers": [], "minScale": 0, "maxScale": 0, "defaultVisibility": false, "extent": { "xmin": -7.82919883203712, "ymin": 55.16116700055115, "xmax": -5.97989177691135, "ymax": 55.43762488398325, "spatialReference": { "wkid": 4326, "latestWkid": 4326, "xyTolerance": 8.983152841195215E-9, "zTolerance": 0.001, "mTolerance": 0.001, "falseX": -400, "falseY": -400, "xyUnits": 1.125899906842624E13, "falseZ": -100000, "zUnits": 10000, "falseM": -100000, "mUnits": 10000 } }, "hasAttachments": false, "htmlPopupType": "esriServerHTMLPopupTypeNone", "displayField": "VALUE", "typeIdField": null, "subtypeFieldName": null, "subtypeField": null, "defaultSubtypeCode": null, "fields": [ { "name": "OBJECTID", "type": "esriFieldTypeOID", "alias": "OBJECTID", "domain": null }, { "name": "VALUE", "type": "esriFieldTypeInteger", "alias": "VALUE", "domain": null }, { "name": "COUNT", "type": "esriFieldTypeDouble", "alias": "COUNT", "domain": null } ], "geometryField": {}, "indexes": [ { "name": "R1310_SDE_ROWID_UK", "fields": "OBJECTID", "isAscending": true, "isUnique": true, "description": "" } ], "subtypes": [], "relationships": [], "canModifyLayer": false, "canScaleSymbols": false, "hasLabels": false, "capabilities": "Query,Map", "supportsStatistics": false, "supportsExceedsLimitStatistics": false, "supportsAdvancedQueries": false, "supportedQueryFormats": "JSON, geoJSON, PBF", "isDataVersioned": false, "ownershipBasedAccessControlForFeatures": {"allowOthersToQuery": true}, "useStandardizedQueries": true, "advancedQueryCapabilities": { "useStandardizedQueries": true, "supportsStatistics": false, "supportsPercentileStatistics": false, "supportsHavingClause": false, "supportsOrderBy": false, "supportsDistinct": false, "supportsCountDistinct": false, "supportsPagination": false, "supportsTrueCurve": true, "supportsQueryWithDatumTransformation": true, "supportsReturningQueryExtent": true, "supportsQueryWithDistance": true, "supportsSqlExpression": false }, "supportsDatumTransformation": true, "dateFieldsTimeReference": null, "hasMetadata": true, "isDataArchived": false, "archivingInfo": { "supportsQueryWithHistoricMoment": false, "startArchivingMoment": -1 }, "supportsCoordinatesQuantization": true, "supportsDynamicLegends": true, "serviceItemId": "fb8b178661ea4acea8fcdfa3f520d94f" }