First off, I apologize for my lack of posts recently… I’ve been busy and haven’t had much interesting to talk about. A hot topic this week has been the release of the Synthesis report from the discussions at the Copenhagen conference earlier this year. This report, in part, is to take off where the IPCC AR4 left off in discussing key developments that occurred after the deadline for AR4 references.
The general discussion is easy to follow (written like it is for newcomers to the topic) and not surprising to people who have studied climate change topics. It has all the usual stuff: The climate is warming, we have high confidence now of a significant anthropogenic signal in that trend, sea levels are rising, ocean heat content is going up, ice is melting, etc, etc. It is still worth noting that many climate observations are exceeding projections.
Combating climate change, and the language necessary to convey the threat of AGW to the public, has been the topic of a lot of discussion. A powerful paragraph issued in the synthesis report is
Past societies have reacted when they understood that their own
activities were causing deleterious environmental change by controlling or modifying the offending activities. The scientific evidence has now become overwhelming that human activities, especially the combustion of fossil fuels, are influencing the climate in ways that threaten the well-being and continued development of human society. If humanity is to learn from history and to limit these threats, the time has come for stronger control of the human activities that are changing the fundamental conditions for life on Earth.
Key finding #5 of the synthesis report is that “Inaction is Inexcusable.” Greenhouse gases will continue to rise substantially over the century unless widespread implementation of renewable energy, management of biological systems (e.g., reforestation), and wise policy action. There is no longer any reasonable doubt of the strong impact of GHG’s on global climate. The Copenhagen synthesis report uses a standard +2 C temperature anomaly as a guard-rail for dangerous anthropogenic interference, and warns of the prospect of not-well-understood “tipping points” and changes which are irreversible on timescales relevant to us and future generations. Postponing action could result in substantial distruption of ecosystems and infrastructure, and could result in a more costly transition into a “decarbonized” economy if humanity chooses to act in the more distant future.