For the last four years I have directed the Rutgers Initiative on Climate and Social Policy  (www.csp.rutgers.edu ). In that capacity I have seen how debates about climate policy often make assumptions that deserve closer scrutiny – which is after all the stock and trade of a philosopher.

Working with a group of climate modelers over the last three years (with support from the NSF- ATM-0730452), I have developed an appreciation for the need to embed ethical issues surrounding climate change mitigation and adaption in the context of risk assessment. But the challenge of applying risk assessment in this area touches on many foundational issues. Of these, the most important center on our understanding of low-probability, high-risk outcomes and on how much weight to give them in policy decisions (see Weitzman 2009).

In my work on geoengineering to date (see résumé), I have argued that planetary-wide solar radiation management (to reduce the amount of sunlight reaching the earth) poses potential risks that are impossible to assess reliably at a sub-planetary level. This is because  on the standard model of the application of science and technology, the road to full deployment has a number of way stations, each of which offers an opportunity to assess benefit under increasingly realistic conditions. There is, of course, a trade-off here. The more the restrictions on  realism, the less the risk but also the less our ability to assess the benefits.  Wherever this process starts, be it in the lab or in a computer model, full scale deployment does not take place before testing in more limited circumstances – in scale, strength,  or range -- except insofar as we have a very well confirmed model. In medicine, even after animal testing, we restrict the number of subjects exposed and increase the strength of the exposure in a series of steps. In medicine we can follow this procedure because of something we take for granted – our object of interest is  reasonably modular or encapsulated. That is what makes it  possible for us to extrapolate from experimental subjects to the population as a whole with confidence. The experimental subject is a full-scale representation of the objects of interest. You can test a vaccine on one person, putting that person at risk, without putting everyone else at risk. Not all of our scientific or technical interests allow for full-scale representation at the experimental level, and in that case we must also be able to extrapolate to scale with confidence.

But what if the object of your interest is not modular or encapsulated? For that, after all, is the feature that planetary-wide  geoengineering proposals have in common. They call for interventions on systems that lack just this characteristic. You can’t encapsulate part of the atmosphere, and it is too complex to be able to build a realistic non-virtual model at scale. As such, it is reasonable to ask if we could ever have a sound basis to move to full deployment of any such proposed intervention. And if not, then why bother to even research such proposals in the first place?

In this project my aim is to expand this kind of approach to examine the interplay between risk assessment and ethics for climate change policy beyond geoengineering. Doing so has both a prescriptive and a descriptive dimension.

Policy questions about avoiding climate change involve decisions under ignorance. We don’t know the likelihood of climate change nor its cost. One way to think about such decisions is to do our best to fix the value of  both of these unknowns. Such a project is far from straightforward because it not only touches on our epistemic limitations but also on  theoretical assumptions about  the relative valuation of present versus future costs. (See Stern 2008 and  Nordhaus 2008). In Part I of this project, I contrast this with an alternative approach that seems to sidestep these problems. Never mind what the chances of anthropogenic causes  of climate change really are, or the likely costs. However small the chances are, it is possible that climate change could produce catastrophic outcomes, including complete ecological collapse and with  it the extinction of homo sapiens (see most notably Hansen 2008, as well as Ackerman and Heinzerling 2004,  Posner 2004, and Sunstein 2007).  On one variant of this argument (which I contrast to Weitzman’s (2009) econometric argument), the cost of such an outcome would be infinite if we consider all of the future generations who would be deprived of existence. If we think of the cost of avoiding climate change (in terms of lower rates of economic growth) as an insurance premium to be paid to avoid a worst case outcome, for better or worse, any price would seem “rational” as long as it is less than the cost of extinction. And  that is easy to show if the cost of extinction is infinite without our having to  actually calculate the costs of the insurance premium - perhaps too easy to show given the assumptions of standard decision theory. But what if the cost is not infinite, but merely very very high? (For after all  life on earth will end eventually, if only because the sun becomes a red giant.) Then the calculus  becomes much more complicated. How can I be sure the cost of the insurance premium is not more than the cost of extinction?  I will defend the view that even though the costs of extinction are not infinite, they are high enough that we can effectively ignore the costs of the insurance premium. But to do so, I need to argue that we have an obligation to future generations of human beings. I attempt to not only do that but also to  extend that argument to apply to an obligation to non-humans as well, notwithstanding the philosophical difficulties one encounters in saying just why this is a moral obligation.

In Part II, I begin by stepping back to ask just why we have an obligation to future generations humans, let alone non-humans. The standard literature on future generations assumes there will be future beings but that their identities and numbers are a function of our actions today (see Parfit 1984). It is one thing to think about how my actions now may effect a being  (call him Henry) who will exist a hundred years from now. It is another to think of how my actions now may result in another being existing in the future instead of Henry (Henrietta) . Now suppose my actions produce Henrietta rather than Henry and my actions render her life of lower quality than what his life would have been. Henrietta can have no complaint – but for my actions she would not have existed. And Henry never existed, so what rights of his did I violate? But surely I did do wrong, and capturing that is the philosophical challenge addressed in the existing literature on future generations. But what if my actions now cause human extinction in the future? So neither Henry or Henrietta exist. Then whom have I wronged?  Constructing a philosophical framework to support the intuition that here too I have done wrong, even though I wronged no one, is the challenge I take on in Part II (making use of Roberts and Wasserman 2009 and Mulgan 2006). Doing so lays the groundwork for a much more controversial project – to make sense of the idea that our actions can also wrong non-humans. That argument is not hard to make for non-human sentient beings that are thereby assumed to be rights bearers. But I am interested in  examining the argument for things that have no chance of conforming to such a standard  like trees (see Stone 1996) or more generally nature as a whole. This is no easy argument to make, even on consequentialist  grounds. As such it forces us to confront the question of whether ethics can be extended far beyond the domain that it naturally inhabits, which I take to be the push and pull of organized human societies.

Whatever our obligations to others (and Nature) may be, if we have any, what then? In Part III I examine the question of how we should divide up those obligations.  In doing so I need to argue against three prevailing tropes. The first trope is that the problem of climate was caused by the Developed World and so it is up to the Developed World to solve the problem. The second trope is that clean energy is available, it is just a question of whether we are willing to pay the higher costs for using it and who should pay those costs. The final trope is that the interests of the Developing World and the Developed World are aligned in that we all lose in the face of climate change.

I take issue with all three of these claims. It is not that they are false, but rather that they are incomplete. Taken at face value, and so put to use in discourse about climate change, they foster the illusion (in the Developing World) that growth and avoiding climate change are not in conflict. Instead, it is matter a matter of added cost, which can and should be paid for by the Developed World. In the Developed World, these tropes foster the illusion that avoiding climate change trumps development for everyone, but especially the poor. And since the poor are overwhelmingly concentrated in the Developing World, so too, in the end, avoiding climate change will trump development in the Developing World as a whole. So when the parties meet, one side assumes the other can and should pay while the other side assumes that, if they don’t pay, there is not too much to lose, since it is in nobody’s interest to follow business as usual – that is, to fuel growth while continuing to emit carbon.

But scratch the surface and none of this is as straightforward as it may seem at first blush. I will argue that who did what, when, and who owes whom what is not only complicated morally but very dependent on where we stand in time. A few years from now, things will look very different because of the growing output of the Developing World (see Wheeler and Ummel 2007).  So from where we look at things in time matters. The idea that clean energy can be had but that it is only a matter of cost (see for example Stern 2006 and Lomberg 1998)  not only makes assumptions about the availability of such energy but the rate at which the infrastructure to distribute it can be deployed in comparison to the rate of growth of energy demand (see Pielke 2010 ). It also makes assumptions about the likelihood and rate of innovation. Finally, the seeming consensus that, if push comes to shove, avoiding climate change is ultimately in all of our best interests and especially in the interests of the poor, will occupy much of Part III. For I will argue that what may be in the interests of the poor and, with them, the Developing World, may not in fact coincide with the interests of the rich of the world.