The two basic categories of policy responses to anthropogenic climate change are mitigation and adaptation (Füssel and Klein, 2006; Stehr and von Storch, 2006).

Mitigation policy options aim at limiting climate change by reducing greenhouse gas (GHG) emissions and enhancing so-called GHG sinks.

Adaptation policy options mainly strive to diminish the negative effects of climate change by establishing a broad range of policies and measures targeted at the vulnerable system, i.e. change in human systems in response to actual or expected climate change (IPCC 2001b). Adaptation also often includes policies and measures undertaken to seize new opportunities that may have arisen as a result of climate change. More information on mitigation and adaptation plus the main differences between them are found in Table 1.

Table 1. Main differences between climate adaptation and mitigation policy options (Füssel and Klein, 2006)

 

Mitigation of climate change

Adaptation to climate change
Benefited systems All systems Selected systems
Scale of effect Global Local to regional
Life time Centuries Years to centuries
Lead time Decades Immediate to decades
Effectiveness Certain Generally less certain
Ancillary benefits Sometimes Mostly
Polluter pays Typically yes Not necessarily
Payer benefits Only little Almost fully
Monitoring Relatively easy More difficult


Mitigation

In addition to the characteristics listed above, climate mitigation policy options suffer from something known as the Prisoner’s Dilemma. To create effective mitigation, many actors at the global level must reduce emissions. If only a few lower their emissions, the impacts or benefits will be small. There is also uncertainty about the magnitude and pace of GHG reductions that are required to halt the progression of global temperature rise. The most stringent of the six stabilization scenarios assessed by the Intergovernmental Panel on Climate Change (IPCC) in the fourth Synthesis Report, requires a concentration of between 445 to 490 ppm of CO2-eq in the atmosphere (IPCC, 2007b) in order to limit temperature increase to 2°C. To achieve this, GHG emissions have to peak in 2015 at the latest and then decrease dramatically by 50 to 85% compared to 2000 levels until 2050. Even if GHG concentration is stabilized at a higher level, significant emission reduction is still required.

Adaptation

Burton et al. (2006) synthesized results from several local case studies on climate adaptation and identified nine lessons that had been learnt:

• Adapt now,
• Adaptation is development,
• Adaptation is for ourselves,
• International financial help is necessary,
• Strengthen institutions,
• Involve those at risk,
• Use sector-based approaches,
• Expand information, awareness and technical knowledge, and
• Adaptation is place-based.

Several of these lessons have been incorporated in the participatory Vulnerability Assessment framework used in the BalticClimate project.