Water, Air, and Soil Pollution

, Volume 85, Issue 4, pp 2503–2508

Estimating uncertainty in the current critical loads exceedance models

  • R. I. Smith
  • J. R. Hall
  • D. C. Howard
Part V Critical Loads


The critical loads approach to quantifying areas at risk of damage requires deposition and critical loads data at the same spatial scale to calculate exceedance. While maps of critical loads for soil acidification are available at a 1 km scale no monitoring networks in Europe measure wet and dry inputs at this scale and, further, the models currently used to estimate deposition incorporate a number of assumptions which are not valid at the 1 km scale. Simulations of 1 km deposition from 20 km data show that the uncertainty introduced by using 20 km scale estimates of deposition is small, except in mountain areas where it can give misleading results, but a major problem is the uncertainty in estimates of deposition at the 20 km scale produced by the current models.

Key words

critical load deposition model spatial scale uncertainty probability distribution 


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Copyright information

© Kluwer Academic Publishers 1995

Authors and Affiliations

  • R. I. Smith
    • 1
  • J. R. Hall
    • 2
  • D. C. Howard
    • 3
  1. 1.Institute of Terrestrial EcologyEdinburgh Research StationPenicuikScotland
  2. 2.Institute of Terrestrial Ecology, Monks WoodHuntingdonEngland
  3. 3.Institute of Terrestrial EcologyMerlewood Research StationCumbriaEngland

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