Mitigation, Adaptation, and Costs of “Building Resiliency” Preparing Your Coast

Oceans of Change  Though taking action to fight climate change could significantly lessen its effects, greenhouse gases already in the atmosphere have committed us to decades and perhaps even centuries of continued warming.  Coastal communities should therefore prepare to adapt to future changes even as efforts progress to mitigate, or lessen, climate change by reducing greenhouse gas emissions.  Sea level, ocean acidification, sea surface temperatures, ocean heat, and ocean circulation have all been changing in ways unknown for thousands of years.

Oceans of Change (cont’d)  Arctic sea ice melted significantly more in summer in the last 30 years, and storms are intensifying.  Coastal ecosystems stand to be damaged, and coasts will likely erode from the intensified storm surges and flooding brought on by climate change.  Coastal communities will need to prepare adaptation strategies to cope.

Responding to Change  Our nation's experience in managing and protecting its inhabitants, resources, and infrastructure has been based on our relatively stable historic climate.  But adaptation to climate change requires an appreciation of possible conditions that lie outside the realm of experience.  Further, adaptation will require action from a range of decision makers, from federal, state, tribal, and local governments, the private sector, non-governmental organizations, and community groups.  Adaptation can mean both adjusting to the negative effects of climate change as well as taking advantage of any positive consequences of change.

Responding to Change (cont’d)  In the short term, adaptation actions that can be most easily implemented are low-cost strategies with win-win outcomes, ones that offer immediate benefits, and those that reverse poor policies and practices.  Often adaptations make ecological and human structural systems more resilient and healthy, both now and in the future; short-term solutions that make things worse long-term are not good adaptive choices.  Decision makers would be more effective to consider the relationship between adaptive actions and mitigation; adaptive actions that make it more difficult for mitigation are not good choices.

Building Resilience  Building resilience is an important goal related to adaptation and mitigation, and can help coastal communities regardless of the precise effects of climate change.  Improving resilience can mean altering fisheries management to take advantage of new species moving into a region as traditional commercial species dwindle.  It could mean improving migration routes for species that must move to adapt to climate change.

Building Resilience (cont’d)  It could mean restoring natural floodways to improve a community's flood defenses.  It could mean educating the public to let them know how they can help.

Tips for Planners  Few local climate change predictions are available, so identifying trends will be important for coastal planners.  Decision makers should be cautious about plans based on future projections with specific numbers attached, although in many cases states need to determine a specific number within given parameters.  These plans may seem more defensible to stakeholders, but uncertainty in projections could mean that such adaptation plans over- or under- prepare for the future.

Tips for Planners (cont’d)  Instead, decision makers may find it more productive to look for existing vulnerabilities in their communities and map these together with a range of climate change projections to see what areas of concern emerge.  That can provide a starting point for thinking about adaptation options, comprehensive scenario building, hazard planning, and what if/how much exercises.  Decision makers should also consider the possibility of abrupt changes.

Tips for Planners (cont’d)  Such tipping points could create new irreversible conditions like ice-free summers, extreme sea level rise, or sharp increases in extraordinarily damaging weather.  Adapting to these impacts could require consideration of radical adaptation measures like large-scale retreat of populations from at-risk areas.  Prudent communities will consider these kinds of high risk, low probability events in order to have "worst-case scenario" plans on the books.