Levels of waste in the oceans are increasing in almost all areas. Even in the most remote places there are now clearly detectable levels of toxic pollutants, and of litter. Climate change is advancing, and even if levels of greenhouse gases were stabilised immediately, the warming of the oceans and sea level rise will continue to rise for many decades. In a few cases, however, particular types of pollution, including toxins such as lead from petrol engines, have been reduced substantially in recent years. International agreements to ban particularly dangerous chemicals such as ozone depleting chemicals have also had marked impacts. Public awareness campaigns have also proved highly effective, notably in driving efforts to reduce outputs of untreated sewage in many areas.
Responses to terrestrial waste problems must be taken across a broad range of levels, and must be integrated into society as well as into governance. Broad approaches include the halting or reduction of emissions, as well as the mitigation of impacts. Important elements include the development of technical solutions to reduce or process waste, but also mechanisms to finance waste reduction initiatives through direct inducement or financial penalties for waste production or emission. In an effort to achieve compliance it is also necessary to establish support for change, which requires elements of information provision and education. All of this work needs to be placed in a policy framework, with management strategies and institutional structures in place, and in many cases a legal framework and enforcement structure to ensure compliance. These approaches need to be undertaken at levels from the local and national through to the transnational and global.