Figure 1.3

Figure 1.3. Records of non-seasalt (nss) sulfate (SO42-) and nitrate (NO3-) from an ice core in south Greenland, the site is downwind from U.S. and European emission sources. These two chemical species provide a measure of the primary components of acid rain: sulfuric acid (H2SO4) and nitric acid (HNO3), respectively. Data represent yearly averages over the period 1760-1985. Large spikes in nss sulfate are produced by volcanic events that emit large amounts of sulfur gas into the atmosphere. The volcanic events recorded by large, short term emmission of sulfate are: (1) Laki (1783); Tambora (1815). Taken from Mayewski et al. (1990).