New analysis: $17+ trillion exposed to rising seas by 2100

Climate Central is a nonprofit that develops clear explanations about climate change for mainstream media channels and for the public. They do an excellent job in my opinion. One of their areas of focus is rising sea level. A recent article “Adapting to Sea Level Rise Could Save Trillions by 2100” is noteworthy.

Using new upper level estimates for sea level rise this century of four feet, it describes disastrous levels of economic loss — in the tens of trillions of dollars annually by the end of the century — figures rivalling the entire GDP of the US. The very accessible explanation by Climate Central is  based on a new study by the venerable National Academy of Sciences.

Simply stated the NAS paper suggests the tremendous economic benefit from adaptation to higher sea levels using structures as simple as levees. Readers of this blog or my book “High Tide On Main Street” know that my main recommendation is that we need to begin just such a far-sighted program of adaptation ASAP. Sea level will keep rising for centuries regardless of what we do to slow climate change at this point.

While I am glad to see the start of long-term awareness of the effects of slowly rising sea level stated by NAS, I have to note that it is unlikely that we will ONLY have four feet of sea level rise this century given our current path, meaning that those figures could actually be on the low side. (See “Government sea level projection low and misleading – again” explaining that the methods used by the scientific community have a bias to understate the trend.)

Regardless, the sooner we begin to plan for long term sea level rise the better. Given the uncertainties for what lies ahead, I strongly believe that all low-lying coastal areas should begin planning for three feet of sea level rise, recognizing that we do NOT know exactly when that will occur. Planning for three feet of rise will be a significant engineering and architectural challenge, but it is manageable in most locations. The good thing about planning for higher sea level is that it makes communities much more resilient to the unpredictable storm events and to the extreme high tide events that occur regularly with the lunar and planetary cycles.

Those increasing extreme tides (sometimes called King Tides) give us a good picture for what will become normal decades in the future as the glaciers and ice sheets continue to melt, raising sea level, and slowly moving our coastlines inland.

By John Englander February 19, 2014 Sea Level Rise