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Layer: 2020-2021 SAR Seasonal Flood Map [GSI] (ID: 14)

Parent Layer: SAR Seasonal Flood Maps [GSI]

Name: 2020-2021 SAR Seasonal Flood Map [GSI]

Display Field: flood_ID

Type: Feature Layer

Geometry Type: esriGeometryPolygon

Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P STYLE="margin:0 0 14 0;"><SPAN><SPAN>The map shows observed peak flood extents which took place between Autumn 2020 and Summer 2021. </SPAN></SPAN></P><P STYLE="margin:0 0 14 0;"><SPAN><SPAN>The map was made using Synthetic Aperture Radar (SAR) images from the Copernicus Programme Sentinel-1 satellites. SAR systems emit radar pulses and record the return signal at the satellite. Flat surfaces such as water return a low signal. Based on this low signal, SAR imagery can be classified into non-flooded and flooded (i.e. flat) pixels.</SPAN></SPAN></P><P STYLE="margin:0 0 14 0;"><SPAN><SPAN>Flood extents were created using Python 2.7 algorithms developed by Geological Survey Ireland. They were refined using a series of post processing filters. Please read the lineage for more information.</SPAN></SPAN></P><P STYLE="margin:0 0 14 0;"><SPAN><SPAN>The flood map shows flood extents which have been observed to occur. A lack of flooding in any part of the map only implies that a flood was not observed. It does not imply that a flood cannot occur in that location at present or in the future.</SPAN></SPAN></P><P STYLE="margin:0 0 14 0;"><SPAN><SPAN>This flood extent map is to the scale 1:20,000. This means it should be viewed at that scale. When printed at that scale 1cm on the map relates to a distance of 200m.</SPAN></SPAN></P><P STYLE="margin:0 0 14 0;"><SPAN>It is a vector dataset. Vector data portray the world using points, lines, and polygons (areas). The flood extents are shown as polygons. Each polygon has information on the confidence of the flood extent (high, medium or low), a flood id and a unique id.</SPAN></P></DIV></DIV></DIV>

Service Item Id: b67e2f3699d248a2ab90c0b0c880c180

Copyright Text: Contains Irish Public Sector Data (Geological Survey Ireland) licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 (CC BY-NC-ND 4.0) International Licence

Default Visibility: false

MaxRecordCount: 2000

Supported Query Formats: JSON, geoJSON, PBF

Min Scale: 0

Max Scale: 0

Effective Max Scale: 10000

Supports Advanced Queries: true

Supports Statistics: true

Has Labels: false

Can Modify Layer: true

Can Scale Symbols: false

Use Standardized Queries: true

Supports Datum Transformation: true

Extent:
Drawing Info: Advanced Query Capabilities:
HasZ: false

HasM: false

Has Attachments: false

HTML Popup Type: esriServerHTMLPopupTypeAsHTMLText

Type ID Field: null

Fields:
Supported Operations:   Query   Query Attachments   Generate Renderer   Return Updates

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