Acid Deposition data source

Units: keq ha-1 yr-1
Resolution: 5 km
Year: 2019 - 2021 (3 year average)
Data provided by: Centre for Ecology and Hydrology, Edinburgh


Additional Info: Total acidifying deposition is calculated in the following way:

Total acidifying deposition is calculated in the following way:
  Acid Deposition = (S + (NOX+NHX)) - NMBC  where

    S (non-marine sulphur) wet + dry deposition

    NOX (oxidised nitrogen) wet + dry deposition

    NHX (reduced nitrogen) wet + dry deposition

    NMBC (non-marine base cations, Ca + Mg) wet deposition

This calculation assumes that all NMS and nitrogen deposition is acidifying. In practice, a fraction of the nitrogen deposition may be accumulated by the ecosystem resulting actual acidification being less than the figure estimated here. Where acidity critical loads are calculated using the simple mass balance method, the estimated magnitude of the interactions with nitrogen (and with base cations) are incorporated into the critical load calculation.


References: NEGTAP (National Expert Group on Transboundary Air Pollution) 2001: Transboundary Air Pollution: Acidification, Eutrophication and Ground-Level Ozone in the UK. ISBN 1 870393 61 9. Available online.