How do I view and interpret the maps?

The project’s results are available via 20 reports and online maps (web maps). This page provides instructions on how to view the web maps and how to access the dataset for use within GIS.

Click on the questions below to view further information.

How do I view the maps on an internet browser?

  1. To view the web maps, click on ‘See the Web Maps’ on the Dynamic Coast home page or the ‘Web Maps’ link at the top of the page.
  2. This opens another page with an optional video explaining how to use the maps, and links to the web maps. This video will help to familiarise you with the layout and the data on the web maps.
  3. Please read and either accept or decline the ‘Limitations’ message.
  4. This should open up a new tab with the maps. Depending on the speed of your internet connection the maps should load up in less than 30 seconds, , however, could take longer with slower internet connections (e.g. non-fibre).
  5. Read the welcome message and click ‘OK’.
  6. The map displays the position of the shoreline at different times (the survey year is written on each line), above some background mapping. More information on how to interpret the maps are in the 'How should I interpret the maps?' section below.
  7. The screenshot below shows the interface and it's key features. You can familirse yourself with the interface move your cursor / mouse over the buttons, and a description will appear.
  8. To move around Scotland, you can ‘click and drag’ the map to move north, south, east and west. You can zoom in and out by clicking on the and buttons in the map tools area of the interface (top left corner of the map) or use the scroll wheel on your mouse.
  9. To turn on and off layers, click on the ‘Layer List’ button in the top right hand corner. By checking the box each layer it will become visible, by un-ticking it will become invisible (there may be a short time lag as the layers load). If layers don’t appear (an you expect them to) the zoom in or out, and it should become visible.
  10. A ‘Legend’ is also available via the button in the top right hand corner which gives information on the colour codes used for different rates of erosion and accretion (deposition) over the time periods used.
  11. You can click on the lines on the map to get more information.
  12. Within the map tools area you will also find:
    • The ruler tool which allows you to measure distances on the map.
    • The slide tool which you can use to compare two different datasets side by side.
    • The share tool which allows you to share your map with others via a link which you can put an email.
    • There is a search bar which you can use to search for a location (e.g. postcode or town name).
    • Reset which resets the map to it's original position.
    • Location tool which takes the map to your current location.
  13. A variety of lines and datasets are available, a description of each is included in the 'What datasets are available?' section below.

How should I interpret the maps?

  1. The position of the shoreline (Mean High Water Springs) is shown for each of the three time periods: 1890s, 1970s and Modern. Where the shoreline has advanced towards the sea, new land has been created (termed accretion) and where the shoreline has retreated towards the land, land has been lost (termed erosion). The survey dates of each plotted line can be seen by clicking on each line.
  2. The changes are also summarised within the ‘Change 1970 to Modern’ and ‘Change 1890 to 1970s’ with erosion in red, accretion in green and little change in yellow. Like all the datasets, more information (amount of change, rate of change etc.) can be seen by clicking on the lines.
  3. Where the change between two surveys is greater than 10m horizontally, then one can be certain that this is ‘real’ change rather than due to method or surveying error. This is because the width of the 1890s and 1970s line is 1mm on the map (10m on the ground). Whilst many areas of the Modern datasets are better than this, for reasons of simplicity 10m has been used for the minimum change we are confident of as being ‘real’.
  4. There are many possible reasons for the extent and rate of past change (either between 1890s to 1970s, or since the 1970s), so caution is urged in extrapolating past changes into the future. The stability of a shoreline can be affected by the availability, or lack of, coastal sediments, occurrence of storms or flooding, and the construction of coastal defences and dredging that may have occurred between or since the mapping dates. This means that although the NCCA is the first national-level assessment for Scotland, it is intended as a strategic tool and cannot be used to inform detailed local assessments without additional information. For this reason, specific future forecasts of anticipated erosion at precise locations (e.g. a house) are likely to be unreliable, unless they are supplemented by more detailed assessments supported by expert interpretation.
  5. The Future Coast 2050 has been plotted to give a broad impression of the parts of land which lie landward of areas currently experiencing erosion. They are based on the continuation of recent erosion rates landward until 2050 (i.e. 33 years’ time). Assuming the recent erosion rates continue, the dark red areas would lie seawards of MHWS in 2050 (erosion area in the drop-down legend), the pale red would be within 10m of MHWS in 2050 (the erosion influenced area) and the light pink area extends a further 50m inland (the erosion vicinity area) highlighting nearby assets. Future Coast 2050+ has been developed to illustrate the implications if future erosion rates were to double. The implications and impacts of climate change at the coast are being considered in a follow-up investigation.
  6. Past change may not be a good estimate of future change, but it is used here as a reasonable starting point to consider broad-scale patterns. Erosion may reduce or stop due to the arrival of additional coastal sediment or due to the construction of coastal defences. Erosion may also accelerate, for example, due to sea level rise (which is occurring across Scotland).
  7. Summaries have been written for many of the significant changes to the coastline (see the NCCA Cell Reports). These have also been collated within a National Overview NCCA Report which summarises the national picture and, for context, is best consulted prior to the individual Cell Reports.
  8. The maps only reflect position of Mean High Water Springs (i.e. the shoreline) at three points in time (1890s, 1970s and Modern period), and there may be changes between and since that have occurred. So it is possible that change has happened since, or change is occurring away from Mean High Water Springs.

What if I notice a problem with the maps?

Whilst every care has been taken in compiling these datasets, errors may occur.

We welcome reports from the public where improvements can be made. Please use the ‘contacts’ page and if your question relates to a specific location, please use the ‘share’ tool within the webmaps, and include the link within your email.

Please see the FAQ and the rest of the www.DynamicCoast.com website for further information.

How do I download the data to use within a desktop GIS system?

For those with dedicated mapping software on their computers (e.g. ArcGIS) the underlying data is available.

  1. This can be downloaded from SNH Natural Spaces
  2. Or opened via this ArcOnline portal.
  • Scotland’s catalogue of spatial data can be accessed here.
  • Scottish Remote Sensing Index can be accessed here.
(Please note this is under development)

How do I view the data via the National Marine Planning Interactive on an internet browser?

  1. Open NMPI
  2. Search for Coastal Erosion within the search function.
  • Scotland’s catalogue of spatial data can be accessed here.
  • Scottish Remote Sensing Index can be accessed here.
(Please note this is under development)

What datasets are available?

Further information on the datasets are available via the Data Audit Report and Methodology Report.
Name Description
1 Significant recent accretion Shorelines which have moved more than 10 metres (or faster than 0.5 metres per year) since the 1970s. Green lines show where shoreline has advanced seawards (e.g. accretion or land-claim) and the bolder the colour the greater then change.
2 Significant recent erosion Shorelines where the tide line has moved more than 10 metres (or faster than 0.5 metres per year) since the 1970s. Red lines show where shoreline has retreated landwards (e.g. erosion) and the bolder the colour the greater then change.
3 Change 1970 to Modern This shows where the shoreline has moved since the 1970s both seawards (e.g. accretion or land-claim with green lines), landwards (e.g. erosion with red lines) and little change (with yellow lines). The bolder the colour the greater the change.
4 Change 1890 to 1970 This shows where the shoreline has moved between 1890 and 1970s both seawards (e.g. accretion or land-claim with green lines), landwards (e.g. erosion with red lines) and little change (with yellow lines). The bolder the colour the greater the change.
5 MHWS Modern This shows the Modern or current position of the shoreline. It is made up of the most detailed and updated Ordnance Survey data and other more recent survey data.
6 MHWS 1970 This shows the position of the shoreline (Mean High Water Springs) within the Ordnance Survey’s 1970s mapping. Which dates from 1956 to 1995.
7 MHWS 1890 This shows the position of the shoreline (High Water Mark of Ordinary Spring Tides) within the Ordnance Survey’s 1890s mapping (OS 2nd Edition, 6 inch, county series). Which dates from 1950s to 1990s.
8 Coastal Cells (full cells) This shows the large coastal cells which are used to group the coastline into areas which are connected to each other (within a cell) or separated by headlands (in other cells).
9 Coastal Cells (sub cells) This shows the smaller coastal sub cells which are used to group the coastline into areas which are more connected to each other (within a cell) or separated by headlands (in other sub cells).
10 Golf clubs with erosion problems This data was collected by Scottish Golf Union is based on a questionnaire of clubs, showing those who said they have experienced erosion.
11 Remotely Sensed Data Index This is an index of detailed height data (i.e. topographic surveys) across the country.
12 Local Authorities coastal This shows the extent of Local Authorities which have a shoreline.
13 Coastal defences This data set was compiled by the project team, based on available data (including aerial imagery) and expert knowledge. Previously no nationally available dataset existed, so the dataset used here is incomplete. However SEPA have plans to undertake this work.
14 Potentially Vulnerable Areas for Flooding Sections of river catchments, where the risk from flooding on society’s assets (houses, businesses etc.) is considered to be significant. Small parts of PVAs may be at risk from flooding, but the whole catchment section is considered together.
15 Coastal Type (Hard-Mixed, Soft & Artificial) A three-fold classification of coastal type, based on aerial photography analysis:
  • Hard & Mixed – Rocky resilient shores, which aren’t expected to erode enough to threaten adjacent assets
  • Soft – shores made up of potentially erodible sediments.
  • Artificial – man-made shores where coastal defence structures have been built. Erosion is likely to have been an issue or a risk in the past, and may be in the future.
16 Air Photos This layer shows aerial photography, which is often less than 5 years old. It is provided by GetMapping under the Scottish Government’s One Scotland Mapping Agreement.