Obama Presidential Adviser, John Holdren, said of the challenge of climate change, “We will end up with a mix of prevention, adaptation and suffering. It is for us to determine the ratio.”
By Linn Smith
September 18, 2017 ——With the recent flooding in Texas and Florida, it is evident that the rising seas from climate change will affect us by chronic flooding, which will become more frequent. There will be continued flooding and devastation from weather as our climate and seas warm up.
The Union of Concerned Scientists ask the question, “If flooding continues, how many times does it have to happen before you stop thinking of rebuilding and start thinking of relocation? Each community has a threshold for sea level rise and chronic flooding beyond which sustaining normal routines becomes impossible.”
Mitigation or Prevention
Scientist have worried for years that melting sea ice and ocean warming would cause a rise in sea levels, extreme weather and more severe and frequent hurricanes. What is our government’s responsibility? Do we continue to spend our tax dollars on mitigation, cleaning up the aftermath of the increasingly destructive power of storms? Do we continue to rebuild coastal areas that are vulnerable to climate change or do we have a responsibility to reconstruct cities and coastal areas against the coming vulnerability of our changing climate?
William V. Sweet, Scientist with the National Oceanic and Atmospheric Administration stated, “Once impacts become noticeable, heavy rains and extensive flooding are going to be upon us quickly. It’s not 100 years off anymore.” Higher seas mean higher storm surges. As seas rise in an area, the coastal creeks and marshes will rise and bring salt water inland. Many coastal trees will be affected by the saltwater rise.
Reducing the Impact of Rising Seas
What are our choices? Keep spending tax dollars on rebuilding coastal properties or rebuild naturally to reduce the impact of rising seas. A soft shoreline maintains the natural dynamics of the shoreline, with a healthy movement of the sand and improving habitats of sea life. It allows the coastline to do what it does naturally, without the build-up of asphalt and man-made dwellings. A living coastline has natural barriers, vegetation and salt marshes that make it a stronger buffer, against flooding, but also moves and changes as any undeveloped shoreline would.
Obama Presidential Adviser, John Holdren, said of the challenge of climate change, “We will end up with a mix of prevention, adaptation and suffering. It is for us to determine the ration.” There are consequences of inaction!
Hard Structures vs. Soft Defenses Against Wave Energy
What we’ve done with much of our coastal lines to deter flooding is to construct impervious surfaces and blockages to dissipate the wave energy. But there are natural designs that absorb water from storms and channel it back into nature, creating spaces that navagate the water naturally.
The current method of deterring sea wave energy are hard structures. Hard structures, such as sea walls, deflect the wave energy to adjacent areas, redirecting the wave to a neighboring property. These properties witness a greater destructive energy than the original destination of the wave. Walls can fail and waves can erode sand at the base of the seawalls. Walls can also be destructive to the surrounding flora and fauna, which may be preventing a more serious flooding disaster. Hard structures won’t save our cities from rising seas!
The better approach according to Rachel Gittman, Ecologist, is to create living shorelines. A living shoreline is site specific according to the natural habitat of the location. She states that for calmer waters, build water absorbing marshes with sill-like ledges made of rocks, oyster shells or coconut fiber logs. A shoreline may also benefit from planting mangroves, which firmly anchor the shoreline in place.
Natural Barriers of Wave Energy
Steven Scyphers, Coastal Scientist, states, “It starts with a good understanding of what the natural conditions along the shoreline once were. It could mean restoring what existed on the shore, whether oyster reefs, coral reefs or other living breakers that can dissipate the wave energy. These natural barriers become more suitable over time as the plants, roots and reefs grow.”
By 2100, 490 communities could be chronically flooded including Boston, L.A. and most of NYC. Communities will have to decide what will be best for them, flood walls, living shorelines, elevating structures or to retreat. Cities that are below sea level probably won’t be benefited from natural shorelines.
In the meantime we need to change our behaviors to slow down climate change!
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