March 10, 2010

Science can only do so much...

In his column in Nature this month, Dan Sarewitz gives a very clear assessment of the current foundering of climate scientists.  He points out that in the case of climate, we have asked Science to carry out a task that is best left to Politics.

Climate science has made it clear that Earth's atmosphere is warming due to increasing accumulation of CO2 in the atmosphere.  It is becoming increasingly clear that that same CO2 is changing the pH of the surface waters of the global ocean in ways that will make it harder for the bottom of the ocean's food chain to function.  A number of consequences of the increasing heat content of our planet's atmosphere are also beginning to become evident, in particular increases in the variability of weather and climate.  Climate science has also established with reasonable certainty that humans have a discernible influence on the atmospheric changes that are currently underway.

Climate science does NOT tell us that these things are bad.  The scariness of glacial retreat, sea level rise and other effects in the climate litany is a human response to those things.  There is no external reference frame that we can call on that will impose mitigating or adapting actions on the part of humans.  We must CHOOSE to do those things ourselves.

Choosing what to do next has at least two components.  The first, and most argued about, is the resource component.  Should we reallocate resources currently allocated to X over to Y?  The second element has to do with norms and values.  Is switching from X to Y the right thing to do independent of the associated risks and benefits.  Science can help us place boundaries on some of the benefits and risks of switching from X to Y; but it cannot tell us which choice is better.

The choice of better is political and, as we have seen over recent decades, it has time and space varying components.  I will reiterate - there is no external framework that can unambiguously impose a choice on how we should re/allocate our resources in the face of human impacts on our planet.

Humans can, and I would say very likely will (albeit through passive rather than active means) , choose to continue to use the atmosphere as a dumping ground for CO2.  This choice makes me quite sad, and I think it will prove to be a costly folly with respect to human well being.

But the sooner that we start talking about this choice in the context of political tradeoffs rather than scientific uncertainty and foibles, the better off we will be and the better the decisions we actively make are likely to be.