sulfate
Emissions from ships have much more significant environmental effects; many ships go internationally from port to port and are not seen for weeks, contributing to air and water pollution on its voyage. Emission of greenhouse gases displaces the amount of gas that allows for UV-rays through the ozone. Sulfur and nitrogen compounds emitted from ship will oxidize in the atmosphere to form sulfate and nitrate. Emissions of nitrogen oxides, carbon monoxide, and volatile organic compounds (VOC) will lead to enhanced surface ozone formation and methane oxidation, depleting the ozone. The effect of the international ship emission on the distribution of chemical compounds such as NO_x_, CO, O3, •OH, SO2, HNO3, and sulfate is studied using a global chemical transport model (CTM), the Oslo CTM2. In particular, the large-scale distribution and diurnal variation of the oxidants and sulfur compounds are studied interactively. Meteorological data (winds, temperature, precipitation, clouds, etc.) used as input for the CTM calculations are provided by a weather prediction model.[33]