As international climate negotiations continue here in Cancun, the key challenge is to further the process of constructing a sound foundation for meaningful, long-term global action, not necessarily some notion of immediate, highly-visible triumph. I say this because of some basic scientific and economic realities. First, the focus of scientists (and policy makers) should be on stabilizing concentrations at acceptable levels by 2050 and beyond, because it is the accumulated stock of greenhouse gas emissions — not the flow of emissions in any year — that are linked with climate consequences.
Stavins, Robert N. "Will We Know Success When We See it?" National Journal. December 6, 2010.