When we think about environmentalism, we tend not to consider the oceans because we don’t live on or in them, and they are just there as they have always been, defining the edge of the land that we occupy. Of course, oceans provide us with most of our fish, but in the popular understanding, they are mostly experienced as vast spaces of waves and wet that separate the faraway continents that we visit. So we tend to give much more importance to landscapes that we occupy. And because we live within the thin layer of air that girdles the globe, weather is also a concern to us. But we generally don’t consider that much of our climate and weather is determined by what happens in the oceans.