SPATIAL VARIABILITY IN EMISSIONS REDUCTION STRATEGIES FOR SULFUR AND NITROGEN IN THE UK

The roles of sulphur (S) and nitrogen (N) in causing critical loads ex ceedance across the UK show considerable spatial variability at the pr esent time. Over much of lowland Britain it appears that the environme nt can only be protected by reducing N deposition whilst in upland are as (e.g. most of Scotland and Wales) reductions in S deposition are th e primary requirement. Using the Hull Acid Rain Model (HARM) the effec ts of current and possible future emissions control legislation on cri tical loads exceedance can be explored. Based on HARM output the imple mentation of the UNECE Sulphur Protocol (1994) will bring about a subs tantial reduction in the amount of S being deposited in the UK, especi ally in central and southern parts of the country. Some areas will rem ain where additional reductions in S are required Over most of the cou ntry, however, the need to reduce N deposition will become paramount. The changing contributions and significance of non-UK sources can be e stimated.