Two common myths shape thinking about shipping and oceans. First, ships transport nearly everything we consume. Second, we live on planet ocean, not planet earth. Although each claim is, in one sense, correct, each is also misleading. Ships transport 80-90% of international trade (by weight), they transport only 10.8% of the economy's material footprint. Although the ocean covers 71% of the planet's surface, it makes up only 0.12% of its volume. This article queries these widely accepted numbers. Not to ‘correct’ them but to highlight the need to question the common myths that all too often guide environmental intervention.

Ships transport 90% of everything. The planet is 71% ocean. Environmentalists reference these statistics when they advocate ‘buying local’ to reduce shipping's environmental footprint. The shipping industry references them to argue that the industry is ‘too big to fail’ and therefore should not be overly burdened by environmental regulations; furthermore, shipping's emissions are said to be ‘too small to matter,’ considering the role the industry plays in enabling globalised consumer capitalism. Yet, this article shows that ships transport only about 10.8% of everything (by material footprint) and the planet is only 0.12% ocean (by volume). This suggests that we should employ the 90% and 71% figures with caution. Evidence demonstrates that environmental policy derived from crude quantification of an industry's significance can have unintended, and at times unwanted, consequences for the world's economy and, crucially, the planet's environment. Although we do not question the global significance of either the ocean or maritime transport, we argue that for appeals to size and scale to be useful in generating ocean consciousness and guiding policy interventions they need to be questioned every time they are invoked.

Ships transport 80-90% of international trade, but only 11% of the economy's material footprint. This wide gap urges us to rethink common myths about the economy and the environment.