Increased acidity of precipitation due to combustion of fossil fuels has been well documented for both the eastern USA1 and Canada 2. The SO2 and NOxemitted by the burning of coal, natural gas, fuel oil and petrol are oxidized in the atmosphere to sulphuric and nitric acids which subsequently give rise to acid precipitation1. However, the SO2 and NOx emitted, and their oxidation products, are not all removed by atmospheric deposition over the North American continent; a large fraction is advected east out of North America3. In a study between 1 May 1980 and 30 April 1981, we have detected acid precipitation (pH<5.6) on the island of Bermuda, which is 1,000 km east of the Atlantic seaboard of the USA. We report here that the acidity of such precipitation is eight times greater on a volume-weighted annual average than rainwater in natural atmospheric equilibrium, and that the acids present are almost wholly sulphuric with a small nitric acid contribution. There is a strong correlation between the presence of these strong acids and the meteorological back trajectory of Bermuda storm systems to the North American continent, which suggests long-range atmospheric transport of acid rain precursors to Bermuda, these having similar anthropogenic origins (that is, from remote fossil fuel combustion) to acid rain precursors on the continent. 1982 Nature Publishing Group.
