This post was co-authored by Toni Reale.
Flying into Copenhagen this morning, it is easy to see why the threat of rising seas and associated coastal impacts is taken very seriously by the 5.33 million citizens of low-lying Denmark. More than 40% of Denmark’s residents live in the coastal zone (within 3km of the sea) on the many islands and peninsula, and floods are already a frequent inconvenience as most of the country is susceptible to considerable land subsidence and coastal erosion. Projected sea level rise (which is now thought to be 1.4 meters by 2100) will only exacerbate existing problems along the Danish coasts despite the coastal protections that they already have in place. In fact, just a 50 cm rise in sea level will make storm surges and flooding five times more frequent in some parts of the country.
A Two-legged Approach to Battling Sea Level Rise
According to the Royal Danish Ministry of Foreign Affairs, efforts to effectively protect coastal environments and communities worldwide from the perils of global warming must “walk on two legs.” One of those legs must address mitigating global warming pollution through sound policies that effectively reduce greenhouse gas emissions and the other must support coastal adaptation measures to alleviate the risks and vulnerabilities of impacts like rising seas.
Adaptation measures most commonly discussed internationally include stronger building code enforcement, predictive climate risk-based insurance regulation, shoreline armoring, retreat, water resource management and land use planning to name a few. Even if we were to shut down all greenhouse gas emitting sources today, there would still be warming inertia in the global climate system (from CO2) for a couple hundred years. We are therefore committed to a certain amount of sea level rise that we must adapt to.
Ahead of the curve?
One would think that since the Danes have been trying to hold back tidal rivers and seas for generations with their elaborate dike systems that they would be way ahead of the curve on adapting to sea level rise. However, research suggests this is not necessarily the case.
Until recently, the Danish government has been taking a “wait and see” approach to sea level rise adaptation. According to a 2008 peer-reviewed article in the Journal of Coastal Research, titled Danish Attitudes and Reactions to the Threat of Sea-Level Rise, the authors conclude that the Danish attitude toward human-induced climate change has so far been ambiguous. They say that while there has been a strong political push to mitigate global warming pollution that there has been a near absence of national adaptation planning.
A case in point; in late 2008 the Organization for Economic Cooperation and Development produced a report that highlighted the need for the city of Copenhagen to build a series of dikes along the coast to prevent flooding due to ever-rising sea levels. While this report stated that most of Greater Copenhagen is well protected, the city itself is not equipped to handle the type of sea level rise that leading scientists are expecting. In response to this report Connie Hedegaard, Denmark’s Climate Minister, said that although the report presents accurate costs of climate change impacts, she feels that it is based on too much of an unpredictable future.
Responsible Planning Based on Sound Science and Common Sense
Unlike most of the coastal United States, the Danish government enforces very strict spatial planning regulations that, in the absence of national adaptation policy, currently serve as the main instrument that protects people and infrastructure from storm surges and rising seas. Coastal defense measures such as the building of dikes and beach renourishment projects, however, are only implemented when there is a demonstrated need.
Denmark is now beginning to slowly implement sea level rise adaptation measures into their municipal planning process. A great example of science-based planning can be found in the new town of Ørestad, located on a reclaimed island just east of Copenhagen. A subway connects Ørestad to the center of Copenhagen. Assuming a 0.52 meter rise in sea level by 2100, city planners elevated the city’s squares and entrances to the subway. Government officials found that the additional costs to account for sea level rise in this case were marginal. More expensive anticipatory measures such as increasing the height of the major bridge were not taken into account.
International Adaptation Collaboration is Key
Tackling sea level rise adaptation is not an issue to be taken on alone. International groups like SafeCoast have brought together policymakers and coastal managers from the five countries that boarder the North Sea (England, Netherlands, Denmark, Belgium and Germany) together to exchange information, ideas and resources regarding flood and coastal risk management. SafeCoast staff concludes that this collaboration has proven useful because different countries focus on different mitigation strategies to reduce the risk of hazards to people, property and the environment from “jointly faced challenges”.
What does this mean for the Southeast?
Hopefully, as a by-product of the climate talks I am here to observe, the United States will join or create a group such as SafeCoast to help find solutions to keep our vulnerable Southeast coasts livable and productive in the face of rising seas. What we can learn from Denmark is that the foundation for keeping our shores resilient to sea level rise must be built on a solid foundation of both mitigation and adaptation. In terms of mitigation, the Southeast (which if it were its own country it would be the 6th largest emitter of global warming pollution in the world) has a lot of work to do, yet the region has a lot of potential to reduce our contribution to global warming. These conversations are happening and some progress is being made in our Southeastern states.
Coastal adaptation conversations, on the other hand, need to begin at all levels of government in a very serious way and soon. According to the recent U.S. Global Change Research Program’s report, “sea-level rise and the likely increase in hurricane intensity and associated storm surge will be among the most serious consequences of climate change….and the most costly”
“Even with no increase in hurricane intensity, coastal inundation and shoreline retreat would increase as sea-level rise accelerates, which is one of the most certain and most costly consequences of a warming climate.” – US Global Climate Change Program Report on Southeast specific impacts.
Our low-lying coastal communities will become inundated by rising seas more frequently and some permanently. Currently our coastal infrastructure is not designed to withstand these sorts of impacts. Local governments will need to be prepared, and they may need help from our federal government. Perhaps while our elected officials in Washington, DC are advocating for international and wildlife adaptation funds as components of a meaningful climate and energy policy, they should also be advocating for funds for their states to help our coastal communities and businesses adapt to the eminent threat of rising seas.