2021/5/11
Sea Level Rise
Columbia physicist says forethought saved NYC billions in wake of Sandy
WTNY – Thanks for doing this. I just want to introduce you - Klaus Jacob is a geophysicist and an Emeritus research professor at Columbia University's Lamont Dougherty Earth Observatory. Thanks for doing this.
Dr. Jacob – You're most welcome.
WTNY – I would like to open this by asking you to discuss your "Three Ways" theory of adapting to the sea level rise.
Dr. Jacob – Well what has been so far most commonly used is the first approach, defend; build barriers, levees, dykes you name it, which have a long tradition around the world, largely promoted by Dutch experience. This approach worked for several hundred years perfectly well as long as sea level was almost the same over hundreds of years. It would rise a few inches or centimeters but nothing like we see now or will see more so in the future. So, defend against, that has been the first line of approach.
The second approach is "Accommodate" the water. Let the water in and live with the water and adapt to it by raising houses, where that is possible, on stilts, not attached houses like it is often seen in cities, or else giving up the lower basement or the first floor and moving to
higher in the building ; also relocating some of the critical
infrastructure of the building to higher floors, such that electricity, gas, sewer,
water, communication and so on can continue serving the needs of the residents.
Now the third approach is the political hot potato which very rarely has been used so far, but where it has been used, it has been used very successfully, and that is "managed retreat". Retreat from low-lying coastal areas, tidal areas in estuaries, and that is ultimately the most sustainable way to adapt to sea level rising. So, the three options are Defend, Accommodate, and Retreat to higher ground.
WTNY – You have said, " Rivers equalize in elevation where the ocean is in the future". Can you explain to our viewers what you mean by that?
Dr. Jacob – Well the rivers come from inland from higher elevations until they reach the ocean, and then they empty in the ocean. So, the mouth of the river is always at the elevation of the ocean. As sea level rises the mouth of the river will be still at the level of the ocean but since the ocean has risen, that means that the river and the ocean will merge farther inland at higher elevations. So, that's why it is such a fundamental misunderstanding to build barriers because they try to keep the ocean out and this allows the rivers to equalize with the ocean. They simply would pile up behind the barriers if the higher ocean is being held out, and the river mouth doesn't know that the ocean has risen because there are barriers. The river rises behind the barrier, so barriers are useless against sea level rises. They still can keep storm surges out but whatever the sea level happens to be at any given time, because that's a short-term rise, hours or maybe a few days, and hopefully the river behind the barrier will not rise to an elevation that's dangerous for the people behind the barriers in that short period.
Right now for instance, the Dutch have a program called "Room for the River", which allows more water behind the barriers to accumulate without intruding into cities along their shore. They relocate people out of the river valley to slightly higher ground, there's not much higher ground in the Netherlands, but some higher grounds, and then widen the riverbed for the Rhine and the Meuse River. When there's a storm and the barriers are closed, the rivers has more room to fill up without rising too much in elevation.
WTNY – There are a lot of quotes out there on the internet from you around Sandy
and I was wondering if you could talk about what you thought would happen
when Sandy came, what actually did happen when Sandy was here, and the
lessons that you think people should learn or that you have learned from the Sandy experience.
Dr. Jacob – Now, what was so interesting about Sandy is, that in the years before I was deeply involved with various transportation agencies in the New York City area. The Metropolitan Transportation Authority (MTA) and the Port Authority of New York and New Jersey and other organizations, New Jersey Transit, and so on. And these organizations had either tunnels like subway tunnels or road tunnels or low-lying maintenance parks where the loading stock is kept in the off-time hours when not all trains are being needed. But they are typically all at very low-lying elevations for historic reasons because those are areas were put into place in former marshes, it being the only place available where they could build a parking dock for the rolling stock.
So, I was involved in that study and in the year 2011 we came out with a study that had taken a generic 100-year storm and made it go right for the New York City
area and we were interested in what would happen. We modeled with a
three-dimensional underground tunnel model, the entire subterranean and subway system, with all its entrances and we were analyzing with an elaborate computer code what would happen to the system.
To our dismay and surprise, we found out that for this generic 100-year storm, the subway system would flood within 40 minutes. When we conveyed that to the MTA which operates the subway system, they weren't pleased of course, and the engineers were thinking hard about what to do. The higher-ups, the agency administrator did not get the real message. They just denied it. They had other short-term issues, capital projects, labor issues, payments, and so on. That was on their foremind.
When Sandy approached, I watched it very carefully, and I was in
communication with the people of these transportation agencies, I realized that this storm would be exactly what we had used as a model on our computers or maybe slightly higher even. So, I was quite concerned about that and we talked and then the storm arrived, and I lost contact. I had three feet of water in the living room in my own house, so I was busy. When communication was finally reestablished, I heard on the radio to my great surprise that the MTA declared that within one week the system would run again. I said to myself that's almost impossible because in our study we had four cars that would take 3 to 6 weeks to repair because salt water would get into the signal and relay system, and communication systems and to get rid of the salt in all those electric systems would take a long, long time. What I did not know, was that the engineers that had participated in our study, took the lesson from it, and they told their workers to go into the subway system, into what we call blue tunnels that had been designated to be flooded in our study and they ripped out all electrical signal and control systems, brought them to the surface so they wouldn't flood. When the water was pumped out of the tunnel, all they had to
do was remove a little bit of mud, to bring the systems back in, install them,
and bingo, the whole thing worked, and within one week the subway was running again.
There was permanent damage to the tunnels which was repaired later at the cost of more than a billion dollars, but at least the system was running again. New York City's economic output is roughly four billion dollars per day. Without a (subway) system, the economic output would be highly diminished, so the engineers that run the subway system saved the New York City economy tens of billions of dollars by having the wonderful idea to bring out the systems, prevent them from being impregnated with saltwater and then put them back in and make the system run again.
That's a wonderful model of short-term adaptation. That's not structural, that's operational. You can see that if you prepare for an approaching hazard, an extreme event like hurricane Sandy, then at least you can save lives and save some money. Of course, it doesn't prevent the rest of the urban environment to suffer badly, but it can diminish the impact.
WTNY – I'm interested in your answer to this next question, in the hope that it will get to our Canadian Federal Government. So, up here there's been quite a discussion
about homeowners getting a buy-out at a certain rate to leave a flood plain, to
just go somewhere else. Then I read a quote from you, that quite startled me.
"We have the National Flood Insurance Program that allowed building in red
zones, that are now flood zones." Is there a message here about flood insurance?
Is it irrelevant, important, or was the US National Flood Insurance program just badly administered? What happened there?
Dr. Jacob – Well you have to take a historic perspective. The National Flood
Insurance program started to emerge in the '60s and I think it came about for real in the '70s. Why? Because the private insurance sector, the primary insurers - but also the reinsurance industry that underwrites the primary insurers for extreme events - realized that real estate development in the United States in coastal areas or tidal areas in estuaries had taken on a dimension that made it uninsurable at the rates that the customers would be willing to pay for.
That alarmed both the developers and the real estate industry, who said – "Oh my god, if that's the case, we can't get any new construction going, because banks that give a 30-year mortgage will not do so without insurance, we need a national flood insurance." So, it was under pressure from developers and the real estate sector, and the banks that a national flood insurance program was created, that had affordable rates, and allowed construction to continue in flood zones that the private insurance sector had walked away from, as uninsurable.
So, you had essentially an insurance system set up that allowed risk to
accumulate which was under-insured in terms of the premiums that it collected from the insured homeowners. So, it's no wonder that currently, the National Flood Insurance Program is in the red by 20 to 30 billion dollars. There were several attempts made post-Katrina in New Orleans, but again after Sandy to remedy that situation and to ramp up the insurance rates to bring the system back into the (black) and out of the red. With the politicians you know, patting themselves on the back saying "we are very proud to finally remedy this issue".
Well then, the facts hit the road, meaning the premiums of the National Flood Insurance Program went up to a point where the politicians heard from their electors, "Oh, this is impossible what did you do? Our insurance rates are higher than our mortgage payments, we can't afford that". So they quickly reduced it and brought it back down to where it was with one caveat; they still kept the increase but they spread it out over the next 10 or 12 whatever years, I've forgotten exactly the timespan. So, they ramped it up one step every year so the people would be sort of fooled about it. That's how this country has operated. Short-sighted, short-term fixes, political maneuvering rather than looking the fact in the face and saying we have to do something about it.
That's why I think the managed retreat and buyouts are such an important tool because ultimately that's the only way we can fix the problem if homeowners are not willing to pay risk-proportional premium rates.
WTNY - When I look at a city, perhaps like New York , but I'm more
thinking Miami. If I'm an advocate of Dr. Jacob, how do I go about warning, the
2.2 million people that live on the shoreline around Miami. How do I sell this to
the people when currently everything seems ok, sure people have gotten wet
and there have been issues, but nothing huge. How do I sell a population this
idea that I'm one government person and I want to speak to these many
millions of people, and I really think you should do THIS.
Dr. Jacob - Well that takes courage and leadership, and probably political sacrifice because those politicians that would do the right thing probably wouldn't survive more than their four years of elected office, but that's what it would take. Anything short of that just delays the needed action and then the next Katrina, Sandy whatever will be down there in Miami, will take care of the problem. But, some smart people have heard the message already and so what is happening right now in Miami and its hinterland is the following - the poorer people that served the households, servants and in service functions and restaurants and so on, lived inland in Florida, some tens of miles away from Miami and Miami Beach and traveled every day to their job. They are in a terrain that's some 10 to 12 feet higher than the coastal city. Now, smart money has gotten it and so there is now a grab for cheap housing inland at higher elevations and those poor folks are getting bought out and the rich people take over the land and build new "McMansions" as we call them here; little new castles up there called "gentrification" and this has been taking place already for the last several years and it only will accelerate, and probably will more so accelerate if the next storm hits Miami Beach.
In the meantime, Miami Beach is doing something, from where I sit, rather foolish, but to them it looks like a short-term solution. They are developing more levies and buying hundreds of millions of dollars of equipment to pump out what’s called the nuisance flooding water that accumulates during a new moon and full moon when the tides are a little bit higher, and it shows up in the streets there. So, they are pumping this out, but that’s foolish because Miami Beach, and Miami for that matter, sit on former coral reefs and that is very porous limestone and so the ocean water doesn’t come over the levies, it comes through the ground.
So, what they are doing is simply circulating the ocean water that comes through the ground and pours up onto the streets and back out into the ocean just to come back after a few hours. So this is a short term solution that completely neglects the geological reality and sea level rise realities. It may delay giving up some properties for a few years and maybe even a decade but at the high costs of running all these pumps. It's fiddling around on the edges, it's not even a band aid. That wound will get bigger and bigger and eventually these coastal properties will have to be given up.
WTNY – My second to last question. Do you see at some point in the future these
doomsday scenarios where you have populations sort of running away literally the week of an incident, "environmental refugees" so to speak, do you see anything like that with what you know and your predictions for seawater rising and this kind of thing in the future?
Dr. Jacob – Well, each storm will bring a new group of victims regionally or locally
constrained to a certain area where that storm hit, and over time even smaller storms, which occur more frequently will reach the same level that only a big storm right now can hit, given that the sea level right now is still lower than it will be in the future. So smaller storms, in combination with sea-level rise, will reach those places that are hit right now only by big storms. Which means ever more frequently, because smaller storms occur more frequently. Therefore, we will see more and more demand for people asking to be bought out, begging to be bought out.
As we had for instance in one community here within the borders of New York
City one of the islands called Staten Island, where a community in Orchard Beach and adjacent communities had asked the city for years to be bought out, and the city didn't want to have any part of it. And so when Sandy hit and destroyed this entire neighborhood there was a chance but the city still wouldn't do anything. So, they went to the elected state representatives in Albany in New York State Capital, and they turned to the governor who had control over the state disaster relief funds and said would you please buy us out and the governor set aside close to 1 billion dollars to do that. That was at least a good pilot program where a community wanted to be bought out, and we will see more and more that the demand will come from the communities not from the government and the government will need to respond to the needs of those communities.
WTNY - So by all appearances here you certainly seem to be a big picture scientist. For the last question, would it be a smarter idea for nations around the world to try and meet these emission targets and try and mitigate, stop oceans rising, or do you think that moment is long since passed and we need to be dealing with it, what is your point of view here?
Dr. Jacob – Well we have to do both. Just like with the epidemic right now. We often
hear the term " flatten the curve" meaning we have to reduce the people infecting each other, which makes the curve of infections go up rapidly. Well, we have to do the same with greenhouse gasses and we are still emitting in the atmosphere right now. We have to reduce those, flatten those emission curves and that will avoid truly catastrophic situations not only decades ahead but centuries ahead.
So instead of a few meters of sea level (rise), we can avoid tens of meters of sea level (rise). If Greenland and Antarctica first, and maybe more portions of the Antarctic ice sheet falls into the ocean it would be tens of meters of sea level rise. So, given that situation, we have to, unfortunately, do both, because we have already front-loaded the atmosphere with so much CO2 and it takes several hundred years for that C02 to get first dissolved into the ocean then transformed into seashells by ocean critters that then fall to the ocean floor as limestone essentially or carbonate and that process takes hundreds of years. So, given that we have front-loaded the atmosphere with so many greenhouse gases, CO2 in particular, sea levels will rise even if we were to stop emitting CO2 into the atmosphere TODAY, and we are not there, by any measure.
So, we have to strive at least for the Paris agreement goals and that will not be enough. Even with Paris, sea level will rise for the next hundred to two hundred years at an increasing rate and only then it will flatten even if we were to stop emitting any CO2 today. So, if we do not stop emitting CO2 then our children's children's children's and grandchildren, they will get the brunt of this sea level
rise in the order of tens of meters and that's why we have to do both. We have to retreat from what we already have imbedded in terms of sea level rise by putting all the C02 in the atmosphere in the past 150 years and we have to stop it on top of that, on top of retreating from the oceans low lying coastal areas by not putting more CO2 or greenhouse gases in the atmosphere to prevent further damage to generations beyond that.
WTNY – Dr. Jacobacob, I want to thank you for doing this. I've learned a lot I found this quite fascinating thanks very much.
Dr. Jacob - Good luck.
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