Global climate change impacts merchant shipping and is exacerbated by it.
Ship operations are estimated to account for 2 to 5 percent of carbon emissions worldwide. Ship operators will increasingly face national regulations and international conventions intended to reduce this. It has been noted that to meet the targets of the Paris Climate Agreement, all cargo ships would need to achieve zero-emissions status by 2050. At the same time, the demand for marine transportation is projected to increase as, for example, some countries move cargo and passengers from landside modes to water transportation to reduce congestion and increase efficiency. This will make it more difficult to minimize the environmental impact of shipping.
Climate change will affect shipping in both positive and negative ways. Rising sea levels will make many harbors more accessible for deep-draft vessels. Melting polar ice may open new navigation routes. Warmer temperatures may result in extended seasonal access to waterways that normally freeze over in winter.
But warming oceans may well mean increasingly frequent and more dangerous tropical storms and hurricanes. Rising sea levels will reduce clearances under bridges and power lines. Ports and associated transportation infrastructure may have to be reconfigured to deal with changing water levels. Longer, more intense heat waves may reduce worker productivity and affect cargo-handling and other equipment.
For the industry, some of these developments will result in cost savings, while others represent expenses. The need for strategies to leverage the opportunities and mitigate the costs is clear. Alternative ship propulsion is one area of real promise. Sail-assist, fuel cells, electric drive, bio-fuels, and a number of other technologies need further development, but could ultimately cut operating costs and reduce emissions. Forward-thinking governments and investors must find ways to support the research needed to advance and deploy these fossil fuel alternatives.