Throughout April and May, international headlines were dominated by a deadly hantavirus outbreak on a Dutch cruise ship. The saga provided the perfect opportunity for many to renew their critiques of the cruise industry, asking why – in a post-COVID world – anyone would want to go on a cruise. They’re expensive, they’re exploitative, they pollute the oceans, and – as evidenced by recent events – they’re ideal vectors for the spread of disease.
As someone who works in the field of climate justice, my main concern with cruise ships is (predictably) their contribution to the worsening climate crisis. Just one cruise company – Carnival Corporation – emits around 9.5 million tons of CO² annually. That’s the same quantity of emissions as the entire state of Rhode Island. On an individual level, the daily carbon emissions of a cruise vacationer are around eight times that of an equivalent land-based vacationer.
In 2011, nearly all countries agreed to limit the global average temperature rise to no more than 2°C. Achieving this goal will require us to keep our global carbon expenditure below 2900GtCO². At the time of writing, we’ve got slightly less than 412GtCO² left. That’s about 49.6 tons of CO² for every person on the planet. Here in the USA, we each emit an average of 14.2 tons of CO² per year – which means we’ll burn through our equal share of this carbon budget in less than three and a half years. After that point we will, essentially, be co-opting someone else’s share. Recognition of this fact should hopefully spur us on to do what we can to reduce our individual carbon emissions. But working out precisely how we should do this – what kinds of reductions it’s fair to demand from us – is the tricky part. After all, almost every aspect of our lives – from eating, to traveling, to powering our homes – contributes to carbon emissions. Are we under an obligation to make reductions in all of these areas?
Probably not. And Henry Shue’s distinction between subsistence and luxury emissions provides us with some helpful machinery to understand why. Since it’s vital that we avoid climate catastrophe – and since doing so requires us to stay within a global carbon budget – a sort of prioritization of emissions is necessary. On the back of this, Shue describes “subsistence emissions” as those that stem from the fulfillment of vital needs, while “luxury emissions” are those that do not. Shue argues that “it is not equitable to ask some people to surrender necessities so that other people can retain luxuries.” In other words, each of us has a moral obligation to reduce (as much as possible) our luxury emissions, but not our subsistence emissions.
Conceptually, it’s a simple distinction. In practice, however, it’s much more complicated. What, precisely, counts as a “vital need”? Food, water, and shelter seem obvious contenders. But even there, we must be careful. The fact that I need food to survive doesn’t mean that all of my diet-related emissions will count as subsistence. If, for example, I’m full after dinner, then a superfluous late-night Hot Pocket won’t count as fulfilling a “vital need.”
So where do cruises fit into all of this? At first glance, it might seem that a cruise is a clear example of a luxury emission. But Shue’s machinery is more nuanced than this. As I noted when discussing the carbon cost of gaming, our vital needs go beyond mere survival and likely also cover important parts of our social lives. And there’s no doubt that – for some – cruises are enormously important. They’re a source of joy and fulfillment; an opportunity to forge social bonds and explore the world.
Whether cruise emissions count as subsistence really comes down to whether or not our list of “vital needs” is subjective or objective. What do we mean by this? Well, to say that this list is subjective is to say that it’s determined entirely by the preferences and desires of the relevant individual. Put simply, if someone decides that something is – for them – a vital need, then it is. If the list is subjective, then it’d be quite possible for a cruise to be included. The problem, however, is that taking a subjective approach to vital needs seems far too permissive. Essentially, it would mean that anything goes. Someone who insists that a weekly flight to Paris is a “vital need” could then count the emissions resulting from their flights as “subsistence” – and therefore be under no obligation to reduce those emissions.
It would seem, then, that the list of vital needs must instead be objective – that is, essential for all people, regardless of their preferences and desires. Perhaps I don’t really care about keeping warm in the depths of a cold winter. Be that as it may, there is a fact-of-the-matter that without sufficient warmth, I will not survive. The same is true of food and water. These are vital needs for all people. Would taking a cruise appear on this objective list of vital needs? Certainly not. There’s no reason to think that such a niche experience is – objectively – essential for all humans. We can demonstrate as much by considering all of the humans who manage perfectly well without ever having set foot on a cruise ship.
But a new problem arises – might our list of vital needs now be too restrictive? As I’ve argued before, education is a good candidate for a vital need. And, if so, then emissions associated with this activity (the carbon cost of getting to school, keeping the classroom lights on, and using a laptop to complete an essay) should count as subsistence. But here’s the thing: less than 40% of Americans hold a college degree. This indicates that many are perfectly capable of living without a post-secondary education, and would seem to imply that higher education has no place on an objective list of vital needs.
Perhaps, then, something is missing from both the subjective approach and the objective approach. Perhaps an alternative is required. This is what I will turn to consider next time.
