PLEASE READ BEFORE TO USE THE GIS TOOL
Ireland: Ireland was added to the APIS GIS tool, for site designations SAC, SPA, NHA and woodlands, using EMEP estimates for 2018 at a 1km resolution.
Empirical Critical Loads for Nitrogen – In Ireland ranges for empirical critical loads for Nitrogen for habitats use the values presented in Table 3.2 of the report ‘Nitrogen–Sulphur Critical Loads: Assessment of the Impacts of Air Pollution on Habitats’ (2021)
UK – For the UK, the database went through a major update, with the addition of mid-year 2020 at 1 km resolution for all pollutants, which means all results displayed for the most recent available year (such as under Site Detailed Grid Information) covering the years 2019-2021.
Pollutant values display has been altered at low zoom levels on the main pollutants map. It now highlights the origin of each estimate nearby the Northern Irish border (using a colour system, and indication in the box in the right hand side on the atmospheric models in use).
We are today releasing another major database update for the UK: all pollutants data is now available only at 1km resolution (except for UK source attribution, still at 5km), including the mid-years 2003 to 2020 for the UK. This does not affect any legacy assessment work made using the GIS tool prior to this update, when the data for UK pollutants up to 2018 inclusive was at 5km resolution for N/Acid deposition and Ammonia. For current assessment work you may want to re-check your pollutant values with the 1km set.
Empirical Critical Loads for Nitrogen – In the UK ranges for empirical critical loads for Nitrogen for habitats use the revised values from Table 1 of the report ‘Review and revision of empirical critical loads of nitrogen for Europe’ (2022)
App issues: Several glitches have also been corrected in this new version. Please continue to report any issues with us by using the contact form so that we can troubleshoot any issues. We are also, as ever, eager to hear your feedback and suggestions to improve this app.
We are also aware of the recurring issue about the app not being available without notice (e.g. proxy errors), and apologize for the inconvenience. We are still investigating this issue, and hope to provide a working solution very soon.
We expect in the future to expand the pollutants time series for Ireland, and updating the app server logic to stay up-to-date with the latest evolutions of the technologies we are currently using.
Details about deposition:
Different deposition estimates are presented for each grid cell: Moorland (included in semi-natural in Ireland), Forest (split into deciduous and coniferous in Ireland) and Grid-Average. Moorland deposition is relevant for short, open vegetation that does not receive fertiliser, such as heathland or calcareous grassland. Woodland receives more deposition due to a greater overall surface area, and Forest numbers can be applied to all wooded habitats. Grid-Average takes into account urban areas and fertilised farmland within the grid cell. These areas receive less deposition than unfertilised habitats, so Grid-Average deposition is generally less than the Moorland deposition, particularly in grid cells with large areas of arable or improved grassland. Grid-Average deposition is provided to allow estimation of total deposition for catchment-wide studies.
Direct deposition onto habitats with little or no surface vegetation, such as freshwaters or shingle, will be less than onto moorland in the same location, but modelled deposition rates are not currently available for these habitats. Using the EMEP4UK model, direct deposition of total nitrogen onto freshwaters has been estimated at 63 % of the deposition rate onto moorland. This proportion of the local nitrogen deposition onto moorland could be used as an estimate of direct deposition onto freshwater within the same grid cell, but measurements are scarce and the proportion remains uncertain. The nitrogen or acidity that enters freshwaters as a result of atmospheric pollution also depends on leaching rates and lateral flows from the land uses within the catchment.