If tribal cultures could consider the seventh generation, we with our much greater power should be considering the seventieth. The thirty year horizon that economists and politicians consider very long range is just a blink in the geological history of our planet. Now that we dominate surface processes of the earth we have taken over the responsibility for its sustenance. Our obligation to our descendants and our world doesn't end when the discount rate kicks in.
Our minimal goal is to avoid an abrupt human population collapse, which in retrospect, if there are any survivors, will be eventually be called a "world war". The carbon problem is a serious threat to sustaining human population in the long run. Although it is one threat among many, it is imminent. The time to address it has come. The energy shortage problem is temporary, but any solution that doesn't deal with the carbon problem is disastrous. I am pro-nuke, pro-sequestration, pro-renewable including big hydro projects, pro-biofuels, conscious of the drawbacks and risks of all of these. Any geoengineering that targets temperature rather than carbon is worthless. You can call me an "environmentalist" if you want but that doesn't mean I agree with everything any "environmentalist" says, nor they with me, by a long shot.
Individual conservation action is useful to set an example, and habitual long distance travel especially must be scaled back, but such efforts are insufficient in the face of the necessity of bringing 3/4 of the world out of poverty. Vigorous and intelligent policy changes are urgently needed.
While outside investigation of a field should be tolerated, economic theory as it exists is vastly more primitive than climate theory, and deserves much more auditing attention since it claims such vast importance. Claims that "growth" is indefinitely sustainable and always desirable, which lie at the core of most modern interpretations of economics as axiomatic, are at odds with fundamental dynamics of the rest of the universe, and should be treated with great skepticism. The presumption of indefinitely sustained meaningful growth, along with an outmoded attachment to equilibrium models which can't handle and thus ignore long time constants, skews the thinking of economists into recommending minimal and delayed policy action. By claiming to be gatekeepers of policy decisions, economists systematically subvert any attention to the long range trajectory of society.
From the point of view of mitigation policy, we shouldn't be talking about climate theory all that much. It's not that climatology is complete or "settled" as some like to claim we claim; it's a very interesting and fruitful pursuit as sciences go these days, and it may well have application value in adaptation planning. It's that the carbon question, which is crucial for policy, isn't a close call anymore, and hasn't been for about two decades now.
There is too much carbon in the active reservoirs of the earth system, by which I mean the collective stores of carbon which have large annual fluxes, i.e., atmosphere, ocean and biota. It is the total carbon in these places that matters, and it's getting rapidly worse. There isn't anything subtle or marginal about it. Consequences are inevitable, but not instantaneous. One thing many people don't understand is that what we see now is the consequence of decisions made decades ago.
Carbon is by no means the only problem of this sort. Human actions form a first order perturbation on the nitrogen cycle, the phosphorus cycle, ocean biomass, fresh water, bulk minerals and many other important systems. The consequences of many of our current decisions are decades in the future. We are already committed to much larger disruptions of climate and geochemistry than we are now experiencing.
Any controversy about the point that we have committed to disrupting global scale processes too much already is partly due to malfeasance. A few private interests have actively tried to prevent a solution to this problem. Even as major industrial organizations quietly withdraw from such efforts, the efforts persist. A major strategy is to confuse the public. One way of achieving this is to paint sober facts as wooly-eyed fantasies, and serious, moderate thinkers as extremists. They think they're protecting an economic or political interest and doing their job, but they really ought to rethink on ethical grounds.
Most people have trouble believing anybody competent would be so shortsighted as to risk the survival of the planet for a few bucks. I have trouble understanding it myself, but it's apparently true. Some journalists understand the source of the confusion, but most popular media are afraid to report it for some reason. Positions that are at odds with any reasonable interpretation of facts and any reasonable ideas of morality are not challenged in the way the press would have done in the past. As a consequence, the public debate about global change issues is dangerously skewed from the most basic and crucial facts, as currently understood and enunciated by virtually every major scientific body in existence.