Using rates of gravestone decay to reconstruct atmospheric sulphur dioxide levels

Decay losses from marble gravestones spanning the last 130 years were measured using the lead lettering index (LLI). The relationship between decay loss and gravestone age can be described using a power function of the form decay loss = a(age)b. For locations where decay is likely to have been dominated by ‘normal’ rainfall, the value of b tends to 1, while for locations where decay losses were higher in the past b tends towards a value of 2. Using Lipfert's dose–response function it is possible to postdict atmospheric sulphur dioxide concentrations using rainfall records and yearly decay rates derived from the power functions. Comparing the derived historic atmospheric sulphur dioxide concentrations between locations, the highest levels are found in the industrial location of Swansea compared with the relatively high historic levels found in urban area such as Oxford, Birmingham and Portsmouth. Suburban or rural locations tend to have very low concentrations.