MONSOON CLOUDWATER CHEMISTRY ON THE ARABIAN PENINSULA

The potentially catastrophic environmental consequences of the conflict in Iraq, Kuwait and Saudi Arabia, from mid 1990 to early 1991, have highlighted the need for background atmospheric chemistry measurements for the region. The only known cloudwater chemistry data obtained in the Arabian Peninsula are presented here. The samples were collected near the coast, in the Dhofar region of southern Oman, from 22 to 30 July 1990, immediately prior to the start of the conflict on 2 August. Analysis of the samples for pH, 10 major ion concentrations and 23 trace elements, demonstrates that the cloud water was very clean. Enrichment factor calculations showed the ions have oceanic and crustal origins, whereas trace elements such as B, V, Mn, Ni, Zn, Se, Sr, Mo and Ba have anthropogenic sources. In comparison with three mountain cloudwater sampling sites in eastern North America, the Omani site has higher pH values, higher Na+ and Cl- concentrations, and lower SO42- and NH4+ concentrations.