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Layer: SAR Seasonal Flood Maps [GSI] (ID: 8)

Parent Layer: Historic flooding [GSI]

Sub Layers: Name: SAR Seasonal Flood Maps [GSI]

Display Field:

Type: Group Layer

Geometry Type: null

Description: <DIV STYLE="text-align:Left;"><DIV><DIV><DIV STYLE="font-size:12pt"><P STYLE="margin:0 0 14 0;"><SPAN>The </SPAN><SPAN STYLE="font-weight:bold;">Synthetic Aperture Radar (SAR) Seasonal Flood Maps </SPAN><SPAN>shows observed peak flood extents which took place between Autumn 2015 and Summer 2021. </SPAN></P><P STYLE="margin:0 0 14 0;"><SPAN><SPAN>The maps were 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 maps 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>This flood extent are to the scale 1:20,000. This means they should be viewed at that scale. When printed at that scale 1cm on the maps relates to a distance of 200m.</SPAN></P><P STYLE="margin:0 0 14 0;"><SPAN><SPAN>They are vector datasets. 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></SPAN></P></DIV></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: true

MaxRecordCount: 0

Supported Query Formats: JSON, geoJSON, PBF

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Max Scale: 0

Effective Max Scale: 10000

Supports Advanced Queries: false

Supports Statistics: false

Has Labels: false

Can Modify Layer: false

Can Scale Symbols: false

Use Standardized Queries: true

Supports Datum Transformation: true

Extent:
Drawing Info: Advanced Query Capabilities:
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HTML Popup Type: esriServerHTMLPopupTypeNone

Type ID Field: null

Fields: None


Supported Operations:   Query   Query Attachments   Generate Renderer   Return Updates

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