Sea level rise is dominated by two sources. If the Greenland ice fields should all melt the oceans are expected to rise about 20 feet. If all the ice carried by Antarctica should melt, the oceans would rise by an additional 200 feet. Clearly, humans are playing a dangerous game by meddling with the climate. Such drastic changes are expected to take many centuries….or not. No one really knows.
“’We just don’t know what the upper boundary is for how fast this can happen.’ Richard Alley, a geologist at Penn State University who probably understands ice sheet dynamics better than anyone, told me. ‘We are dealing with an event that no human has ever witnessed before. We have no analogue for this’.”
Scientists generally limit any predictions to the end of the current century. Estimates of how high the seas will rise by 2100 are highly uncertain, but there is a definite tend toward greater numbers for possible sea level increases. The last official estimate by the Intergovernmental Panel on Climate Change (IPCC) came out in 2013 predicting a maximum anticipated rise of about 3 feet 2 inches. Since the data available for that estimate was used, scientists observed an anomalously high ice melt event in Greenland and surprising ice sheet breakups in Antarctica that have raised concerns that the 2013 estimate may be way too conservative. Unofficial estimates now range from about 3 feet up to as much as 15 feet. Goodall claims that 145 million people live on land that will be submerged by a 3-foot rise. A 6-foot rise would be much more disruptive.
So, given that introduction, are many cities planning for significantly higher sea levels? Of course not. Goodell tells us that the seas rose by a mere six inches in the past century, and half of that was due to thermal expansion of the warming oceans. While six inches is significant in some places, the wealthy cities were not likely to have been greatly affected. But there are other effects to consider, overuse of water resources can cause groundwater loss that leads to a region sinking relative to the rising sea. That is one of the reasons Venice has seen a dramatic increase in the number of flooding events in recent years. New York City is also falling relative to the ocean level. Goodell explains that phenomenon as a rebound from an uplift caused by the massive weight over North America during the last ice age. The ice compressed the earth underneath causing a bulging upward of the uncovered areas. New York is gradually lowering to a former level.
Goodell chose to devote chapters to the conditions in Venice, New York City, and Miami, because those cities already have critical issues with sea level even before the coming rise has become significant. Flooding is frequent in both Miami and Venice when tides are particularly high. New York City suffered considerably from the storm surge from Hurricane Sandy. Surely cities already contending with major ocean-related issues will recognize the need to plan for the time when their current problems are extended to include a several foot increase in sea level? We shall see.
Venice’s official concerns with the sea arise not from the recent rise in flooding events, but with a massive storm from over fifty years ago. Venice is built in a lagoon with a passage to the open sea.
“On November 4, 1966, gale-force winds in the Adriatic Sea pushed a wall of water into the lagoon. Venetians awoke to find their city under five or six feet of water. Electricity was cut, heating-oil tanks swamped, ground floors submerged. Strong winds kept the water in the city for the entire day. When it finally retreated, it left the city full of broken furniture, wet garbage, dead animals, and raw sewage. Miraculously, no one died.”
Clearly such an event was intolerable and must be prevented from happening again. A number of solutions were considered before finally selecting one for funding (the MOSE barrier). The idea was to put floatable barriers at each of the three inlets to the lagoon. When not needed, the barriers would be filled with water and sink to the bottom. When needed, air would be pumped in and they would rise and form a barrier. That is way too simple a description for a very complex engineering problem, but that is basically what happens—or what is supposed to happen. At the time of Goodell’s writing it was hoped to become operational in 2018. As of yet, it has not happened.
There is a lesson to be learned from Venice’s experience. Efforts to contend with the sea are complex, difficult to implement, and enormously expensive. Even without conflicts over its need, becoming operational can take a very long time.
“After the 1966 flood, it took more than fifty years to settle on a plan to protect the city, then get it approved, funded, designed, and partially built.”
When the MOSE barrier was designed, sea level rise was not a high priority. The device is thought to be able to handle only a 1-2 foot rise in sea level. If seas rise by more than 2 feet, then water will begin to pour into Venice’s lagoon from other directions as well and the only way to protect the city will involve a wall completely surrounding it. It is not clear that anyone has estimated how long it would take to build such a wall and how much it would cost.
New York City’s moment of truth when its relationship with the ocean changed forever, analogous to Venice after the 1966 flood, was Hurricane Sandy in 2012.
“Hurricane Sandy, which hit New York City in October 2012, flooding more than 88,000 buildings in the city, killing 44 people, and causing over $19 billion in damages and lost economic activity, was a transformative event. It did not just reveal how vulnerable a rich, modern city like New York is to a powerful storm, but it also gave a preview of what the city may face in the coming century.”
New York, like many cities, chose to increase its area by building on landfills. This guarantees that these areas will be at risk to storm surges and sea level rise immediately. The most damaged areas after Sandy were in the landfill areas. Sandy, now six years ago, is not the worst threat that the city can expect to encounter. Meteorologists have long predicted that global warming will bring more intense storms to ride on top of the rising seas, and New York is particularly vulnerable.
“Finally, New York City is a sea-level-rise hotspot. Because of changes in ocean dynamics, as well as the ground beneath the city is sinking as the continent recovers from the last ice age, seas are now rising about 50 percent faster in the New York area than the global average.”
New York City is moving much faster than Venice did to arrive at a solution.
“In 2018, the city planned to break ground on what’s called the East Side Coastal Resiliency Project, a ten-foot high steel-and-concrete-reinforced berm that will run about two miles from East Twenty-Fifth Street don to the Manhattan Bridge. The project, which is budgeted at $760 million but will surely cost far more before it’s completed, is the first part of a larger barrier system, known informally as the Big U, that someday may loop around the bottom of Lower Manhattan….There are plans in the works to build other walls and barriers in the Rockaways and on Staten Island, as well as across the river in Hoboken. But the Big U in Lower Manhattan is the headliner, not just because it cost billions to construct (rough estimates start at $3 billion and rise fast), but because Lower Manhattan is the most valuable chunk of real estate on the planet, as well as the economic engine for the entire region—if it can’t be protected then New York City is in deep trouble.”
What is built into the plan is the notion that the richest regions will be protected because one can’t protect the entire 520-mile city coastline. The very act of protecting some areas is likely to direct waters preferentially at the unprotected areas. It may be unavoidable, but even in the wealthy US, the poor are likely to bear the brunt of the pain.
New York City leapt into action and has created a plan of sorts. That is to be applauded. But the plan is to protect part of itself from another Hurricane Sandy. When Goodell asked why the plan didn’t include protection from about five feet of additional sea level rise, he was told: “Because the cost goes up exponentially.”
So, the city moved much faster than Venice, but the net result is the same: protect from the threat that we know, not the bigger one that we don’t yet know.
Miami, and much of South Florida are among the most threatened places on Earth with respect to sea-level rise.
“More than three-quarters of the population of Florida lives on the coast, where virtually every house, road, office tower, condo building, electrical line, water line, and sewer pipe is vulnerable to storm surges and high tides. As the seas rise in the coming years, the vast majority of that infrastructure will have to be rebuilt or removed. According to a report by the Risky Business Project, a group cofounded by billionaires Michael Bloomberg, Tom Steyer, and Henry Paulson, between $15 billion and $23 billion worth of Florida real estate will likely be underwater by 2050; by 2100 the value of the drowned property could go as high as $680 billion.”
And while New York can conjure up images of sea walls that will one day protect it, Miami has no such option. It is built on porous limestone which water can easily penetrate. Any wall would quickly see water levels equalized on each side. South Florida must also worry, for the same reason, that salty sea water will penetrate sources of underground fresh water and destroy them. Such occurrences have already happened, and they will become more frequent as sea level continues to rise. Miami already experiences regular flooding episodes, not unlike those in Venice. It is already common to view sea water bubbling up out of storm drains and flooding streets and landscaping whenever there is a high tide. Everyone knows that this will only get worse.
Miami has only two options, it can elevate the city, or it can decide to live on the water not next to it. Do either of these options make any sense? Who will produce the studies, issue the calls for innovative proposals? There is no one. New York is a city of structures with high market value and high intrinsic value. Miami is a city with structures of high market value and near zero intrinsic value.
“There are few corporate headquarters in South Florida, no manufacturing to speak of, no entertainment industry (except sports and porn). Even the illegal drug market, which powered the Miami economy in the 1970s and 1980s, has declined. The core business of Miami is real estate and tourism. It is an empire of property and pleasure.”
Are a hundred thousand condo owners going to band together and form a political movement that will demand active countermeasures be taken to protect their property? Will a bold political leader arise and demand increases in taxes so that plans can be formulated and implemented? In Florida?
Goodell tells us that Miami is stymied by the fact that no one feels they own any of the coming risk. The main reason for buying real estate in Miami is to turn a profit and move on. Property owners have nothing to gain by raising issues that threaten their property’s value; rather, their concern is in understanding the issues sufficiently that they can cash in and leave before it is too late.
“….most condo owners keep their units for about four or five years—as long as they can get their money out, who cares what becomes of the place in twenty years?”
Miami, and much of South Florida seems doomed to a watery fate. The rich will leave in an orderly fashion, but those who can’t take their property with them will have to leave it behind. Like the Oakies of old they will possess what they can carry away.
Goodell is probably more optimistic about humans being able to deal with rising tides than this summary might indicate. On the other hand, he did provide this interesting comparison.
“We’re not so different from the proverbial frog that boils to death in a pot of slowly warming water.”
The interested reader might find the following articles informative:
Climate Change: The Water Will Come by Jeff Goodell
Global Warming and the Resurrection of Dormant Diseases
Putting Climate Change in Perspective
Ground Zero for Sea-Level Rise: South Florida
Global Warming and the Holocaust’s Warning: It Can Happen Again
Geoengineering, Volcanoes, and Climate Change Experiments
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