Variations in the weathering rate of Scottish gravestones as an environmental signature of atmospheric pollution

The weathering rate of marble gravestones has been measured in cemeteries throughout central and southern Scotland. Gravestone weathering rates can be calculated by measurement of the depth from the lead lettering to the current marble face, followed by division by the age of the gravestone. The site average gravestone weathering rate (AGWR) ranges from 4.1 to 20.8 mu m/year, with an average for Scotland of 8.5 mu m/year. There are zones of high AGWR around the Glasgow area and in west Fife, and the AGWR decreases the further the cemetery is located from the industrial and urban belt of central Scotland. By comparison with known levels of atmospheric sulphur dioxide, a map has been produced which semi-quantitatively illustrates the levels of this air pollutant in Scotland during the 20th century.