No More Free Ride: Global Warming Pollution from Ships Must be Regulated (Environmental News Network) Despite their impact on the global climate, greenhouse gases and other global warming pollution from ships remain unregulated by the U.S. Government. These emissions also have not been limited by the Kyoto Protocol or any other international treaty. However, ships are a major source of global warming pollutants, including carbon dioxide, nitrous oxide and black carbon. [News Source]