This chapter outlines the development of nuclear-powered marine propulsion, considering submarines and other naval vessels, together with icebreakers and unsuccessful commercial ships. During shipboard operations, nuclear wastes such as metallic and gaseous radioisotopes are captured by ion exchange and eventually returned to land for disposal. The principal environmental concerns with respect to all reactor operations, apart from something going wrong, are the issues surrounding the decommissioning and ultimate disposal of the spent nuclear fuel, the reactor, and other components that have become contaminated or made radioactive as a result of neutron activation. Incidents relating to nuclear powered submarines are catalogues, noting that the fate of some of the vessels remain unknown. Finally, the Human and environmental consequences of reactors lost and dumped at sea are discussed.

Ships are mobile structures of comprehensive size and at the end of their active life (20 - 30 years of operation), they become a sought-after source of steel. In recent years, over 1000 ships were dismantled worldwide. Shipping companies sell old ships in return for a last profit: about 90% of a ship’s structure is made of steel which is recovered during the demolition process and provides several millions USD of profit for the owner – the amount depending on the size and type of vessel. Obsolete vessels available for scrapping may also represent a useful source of supply for second hand equipment and components. The very nature of vessels represents risks both to the environment, as well as to general safety aspects in the dismantling context. The considerable dimensions, their mobility and the presence of materials and polluting substances, both those integrated in the structure as well as those required for operation, are all factors contributing to such risks. There are at present no international regulatory standards relating to shipbreaking. As a result of this inconsistency, practices and procedures for decommissioning and dismantling, which are in grave breach of basic environmental and human health protection norms, have been adopted in many countries.

Ships are essential facilitators of modern economies – they are by far the most cost-effective mode of long-distance transport for both finished goods and raw materials, and over 90 percent of world trade is carried by sea (IMO, 2017a). There were more than 50,000 ships in the world's merchant fleets in 2015. Bulk carriers – carrying solids such as coal and grains – accounted for about a fifth of the fleet, with a combined capacity of around 705 million tons deadweight. General cargo carriers numbered about 17,000, crude oil tankers about 7000 and container ships about 5000 (Statista, 2018). The amounts moved are staggering; for example, the International Tanker Owners Pollution Federation (ITOPF, 2018) reported that seaborne oil trade has averaged 100 trillion barrel-miles per year since 2000. Financial efficiency pushes for ever-larger vessels, and concomitantly ever-larger canals (Chen et al., 2016) and dock facilities (Mongelluzzo, 2016).

Atmospheric emissions from ships have not been subject to the same regulations as those on land until very recently. Carbon emissions from the shipping industry are low (per tonne of transported goods) relative to other areas of the transport sector, namely road traffic and aviation. Regulatory controls of atmospheric pollutants such as sulfur dioxide (SO2), nitrogen oxides (NOx) and particulate matter (PM) were imposed on land-based anthropogenic emissions, but not applied to ships.

Reinforcing the view that shipping is indispensable to the world, this chapter briefly outlines the shipping industry’s perspective on a range of key topics, notably the issues tackled by the International Maritime Organization (IMO). The commitment of the shipping industry to the protection of the environment is unshaken. The global shipping industry fully respects the role of IMO as its global regulator and participates actively in the development of new and revised regulation to protect the environment. The industry’s focus is not on delaying regulation, but on ensuring that regulation is effective and fit for purpose. It is little recognized outside the industry that virtually every potential impact that a ship may have on its environment is already regulated to some degree under international law. Topics covered in the chapter includes the challenge of reducing CO2 emissions from shipping, the response to the sulfur cap in fuels and ballast water regulations. The chapter also considers ship recycling regulations. Finally, the desire is expressed to preserve the role of IMO as the unique specialist agency for regulating shipping in the face of the trend towards increasing national and regional regulation.

The physical impacts that vessels may cause have not generally been emphasized in the past. However, they are becoming more and more apparent (Roberts, 2011), and this chapter offers a brief overview of the physical impacts that ships have on the marine environment. Numerous mechanisms are considered, together with examples of deleterious consequences. Coral reefs and seagrass communities are highlighted. The impacts of various processes, such as sediment suspension, aeration and microorganism mortality, are described.

One of the most recent threats to any type of water caused by humans is species introduction through ballast water and sediment releases, which may result in harmful effects on the natural environment, human health, property and resources globally. One of the key species introduction vectors is shipping predominantly through species transfers in ballast water and biofouling of vessels (David & Gollasch, 2015a; Davidson & Simkanin, 2012; Ojaveer et al., 2017; WGITMO, 2015). The relative importance of vectors may regionally be very different, and in some regions biofouling may prevail (Carlton & Eldredge, 2009). However, this chapter is limited to ballast water species transfers.

The DPSIR (drivers, pressures, state, impact and response) framework provides a useful conceptual model for assessing and managing problems arising from the interactions between ships and the environment. The DPSIR framework comprises: drivers – the causes of environmental problem (e.g., ship operations); pressures – the effects of the activity (e.g., ship emissions); state – the environmental parameters and components that are affected (e.g., marine ecosystems); impact – the effect exerted on environmental and biological reservoirs (e.g., invasive species, habitat modification); and responses – mechanisms put into effect to prevent and/or mitigate the environmental impacts (e.g., environmental policies, international conventions). A well-established cycle of processes characterizes the continuous means of protecting the marine environment from the deleterious effects of ships. Both end-of-life events – either by shipwreck or shipbreaking – and routine operational performance of vessels exert, respectively, acute and chronic environmental impacts.

Three of the most significant problems affecting the world today are air pollution, global warming, and energy insecurity. This chapter discusses each of these problems, in turn. It starts by discussing the magnitude of the global air pollution health problem today, the sources of the pollution, and how transitioning to clean, renewable energy can solve this problem. It then discusses the difference between the greenhouse effect and global warming and quantifies the major contributors to each. It describes the strength of each warming component, including gases, particles, and direct heat emissions. It also describes how cooling chemicals in the atmosphere mask part of global warming. It then discusses the impacts of global warming. Finally, the chapter describes four types of energy insecurity problems the world faces with the current energy system and how transitioning to WWS can help to solve those problems.

One of the greatest concerns facing the implementation of a 100 percent clean, renewable energy and storage system for all purposes worldwide is whether electricity, heat, cold, and hydrogen will be available when needed. In other words, can a 100 percent system avoid blackouts, which occur when the electric power grid fails because not enough electricity is available to meet demand at a given moment? Similarly, will a 100 percent system always have enough heat, cold, and hydrogen at the times needed?

The solution to global warming, air pollution, and energy security requires not only a technical and economic roadmap but also popular support and political will. In fact, the main limitations of a transition to 100 percent clean, renewable energy and storage are neither technical nor economic; instead, they are social and political. People need to believe that a solution is possible, to understand what changes they can make in their own lives to solve the problems, to make such changes, and to support policymakers who can pass laws speeding a transition. Policymakers, themselves, need to take bold steps in affecting a transition. Thus, one of the most important factors leading to a change is education about what is possible and why it is possible. This textbook aims to contribute toward that education.