Unless Boston builds proper defenses against global warming-driven sea level rise
So, Boston’s Seaport District flooded early this month during a bad snowstorm in the midst of several days of arctic temperatures. And nobody could be less surprised than me. Because I’ve spent a lot of the last quarter century closely following developments in the science of climate change. And the “bomb cyclone” that caused the flooding, and the polar vortex that caused that, are both likely to have been caused by global warming. Yale University Climate Connections just produced a great video that features several luminary climate scientists explaining why at yaleclimateconnections.org. Definitely check it out.
No question, though, that it’s good to live in a region where local government at least recognizes that global warming is a scientific reality. The city of Boston is certainly ahead of most municipalities in the US in terms of laying plans to reduce greenhouse gas emissions enough to become “carbon neutral” and to deal with some of the anticipated effects of climate change. Particularly, flooding from inexorably rising sea levels and increasingly powerful and frequent storms. Which the more reactionary Boston TV newsreaders still insist on calling “wild weather.” But its plans are largely just that… plans. And they are still incomplete and, frankly, woefully inadequate to deal with the magnitude of the crisis facing us all.
Boston city government has initiated an array of climate change initiatives, including Greenovate Boston, a section of the Imagine Boston 2030 process, and—most germane to this discussion—Climate Ready Boston. They are all producing very nice reports grappling with some of the challenges to humanity presented by global warming in the decades to come. But the reports are written by planners and experts who are clearly pulling their punches for reasons that remain somewhat opaque. And in doing so, any good that might come out of the reports and the policy actions that will result from them is essentially undone.
A look at metro planning on global warming-induced flooding is a good way to illuminate the problem in question. The Climate Ready Boston program released a 340-page report in December 2016 that was meant to be a comprehensive assessment of the threats presented to the city by global warming—with plans for possible correctives. It does mention the idea of building giant dikes, storm barriers, and retractable gates (which they call a “harbor-wide flood protection system”) across Boston Harbor as the method with the most potential to save much of the city from major flooding. Which makes sense since Mayor Marty Walsh signed a 2015 agreement with Dutch officials to work together to manage rising sea levels, according to Boston Magazine. And the Dutch are recognized world experts on giant storm barriers and hydroengineering in general, lo, these last few hundred years.
But there’s no firm commitment for harbor-wide defenses in the report. Yet it should be obvious that they are absolutely necessary if Boston is going to continue as a living city for even a few more decades. At least Amos Hostetter of the Barr Foundation—who is a major player in Boston’s climate efforts—put up $360,000 for the UMass Boston Center for the Environment to study their feasibility last year, according to the Boston Globe.
More concerning than its waffling on building big dikes, the big Climate Ready Boston report chooses to focus on the possibility of sea level rise of no more than 3 feet by 2070—although it allows that a rise of 7.4 feet is possible by 2100:
The highest sea level rise considered in this report, 36 inches, is highly probable toward the end of the century if emissions remain at the current level or even if there is a moderate reduction in emissions. … If emissions remain at current levels, there is an approximately 15 percent chance that sea levels will rise at least 7.4 feet by the end of century, a scenario far more dire than those considered here.
Similar caution is on display with an October 2017 Climate Ready Boston report called “Coastal Resilience Solutions for East Boston and Charlestown”—focusing on tactics to protect two Boston neighborhoods on Boston Harbor at high risk for flooding caused by global warming. Once again, the authors’ assumption is that global warming-related sea level rise in Boston will be no more than 3 feet higher than year 2000 figures by 2070. Even though such estimates—which we have already seen are conservative by Climate Ready Boston’s own admission—also indicate that we could face 7-plus feet of sea level rise or more by 2100. And even higher rises going forward from there. Because sea level rise is slated to continue for generations to come.
What’s weird about such methodological conservatism is that a 2016 paper in the prestigious science journal Nature co-authored by a Bay State geoscientist says the lower figures that all the city’s climate reports are using already look to be wildly optimistic.
According to the Boston Globe:
“Boston is a bull’s-eye for more sea level damage,” said Rob DeConto, a climate scientist at UMass Amherst who helped develop the new Antarctica research and who co-wrote the new Boston report. “We have a lot to fear from Antarctica.” … If high levels of greenhouse gases continue to be released into the atmosphere, the seas around Boston could rise as much as 10.5 feet by 2100 and 37 feet by 2200, according to the report.
What’s even weirder is that the same UMass scientist, Rob DeConto, co-authored a detailed June 2016 report for Climate Ready Boston called “Climate Change and Sea Level Rise Projections for Boston: The Boston Research Advisory Group Report” with 16 other climate scientists that look at an array of possible outcomes for the city—and include a discussion of the higher sea level rise figures mentioned in the Nature paper. The report concludes with an admission that current science doesn’t allow for accurate predictions of climate change in the second half of the century. All the more reason, one would think, that models predicting higher than anticipated sea level rise should not seemingly be dismissed out of hand in other Climate Ready Boston reports.
The Globe also reported that a study by the National Oceanic and Atmospheric Administration (NOAA) says Boston can expect a sea level rise of 8.2 feet by 2100. Both 8.2 foot and 10.5 foot estimates are higher than the 7.4 foot estimate that Climate Ready Boston says is possible by 2100, and well above the 3 feet that it is actually planning for by 2070.
The same team that produced the larger Climate Ready Boston report authored the East Boston and Charlestown report; so they are doubtless quite well-aware of all this. Which is evident in this sentence about the (insufficient) extensibility of their proposed neighborhood-based flood defenses: “If sea levels rise by more than 36 inches, these measures could be elevated at least two feet higher by adding fill, integrating structural furniture that adds height and social capacity, or installing deployable flood walls. With this built-in adaptability, their effectiveness could be extended by an additional 20 years or more.”
The point here is not that the Boston city government is doing nothing about global warming-induced flooding. It’s that the city is potentially proposing to do too little, too late (given that most of the flood defenses it’s proposing will remain in the study phase for years, and many will protect specific neighborhoods but not the whole city when finally built), for reasons that aren’t entirely clear. Though it’s probable that those reasons are more political and economic than scientific. Avoiding scaring-off the real estate developers and major corporations that provide much of the current city tax base, for example. The kind of thing that will make life difficult for politicians who then make life difficult for staffers and consultants working on global warming response plans.
Regardless, if experts like the Dutch are basically saying, Boston really needs to build the biggest possible harbor-wide flood protection system to have any hope of surviving at least a few more decades, then we can’t afford to do one of the more half-assed versions of the big cross-harbor storm barrier plan mentioned in the original Climate Ready Boston report—or, worse still, fail to build major harbor-wide defenses at all. If major studies by climate experts are saying that 3 feet of sea level rise by 2070 and 7.4 feet by 2100 are overly optimistic figures, then we need to plan for at least the highest reasonable estimates: currently, the NOAA’s 8.5 feet or, better yet, the Nature paper’s 10.5 feet for the end of the century. It’s true that we could get smart or lucky and avoid those numbers by 2100. But what about 2110? Or 2150? Or 2200? Sea level rise is not just going to stop in 2070 or 2100.
Are city planners and researchers willing to gamble with the city’s fate to avoid sticky political and economic fights? Let’s hope not. For all our sakes. Or the recent Seaport District flood—and numerous other similar recent floods—will be just the start of a fairly short, ugly slide into a watery grave for the Hub.
Apparent Horizon is syndicated by the Boston Institute for Nonprofit Journalism. Jason Pramas is BINJ’s network director, and executive editor and associate publisher of DigBoston. Copyright 2018 Jason Pramas. Licensed for use by the Boston Institute for Nonprofit Journalism and media outlets in its network.