Last month Climate Ready Boston released a new report—a year in the making—that greatly improves knowledge regarding the expected impacts of climate change and the people and places in the city of Boston who will be most vulnerable. Marking the end of the first phase of Climate Ready Boston, an initiative led by the City of Boston in partnership with the Green Ribbon Commission, and supported by Barr, this report provides both the technical foundation and an implementation framework for long-term climate preparedness.
Among the report’s key findings are:
- We will experience more intense rainfall and more extremes of heat.
These changes are already underway; “cloudbursts” (sudden, heavy rainstorms) will expose more than 11,000 structures and 85,000 people to frequent storm water flooding by about 2070.
- Boston will experience sea-level rise greater than the global average, as a result of a unique set of geographic and oceanographic factors.
Because of the inertia already built into the ocean system, seven inches to 1.5 feet of sea-level rise are likely between now and 2050 irrespective of the trend in the global emissions of greenhouse gases. At least three feet of sea-level rise is likely sometime after 2070—with considerably more possible if the world does not get serious about reducing emissions.
- The frequency of flooding events will increase over time.
As the level of water in Boston Harbor rises, flooding along the waterfront that now has a 1% chance of occurring in any given year will increase to 10% after mid-century, and it will occur on a monthly basis—or even more often—by the end of the century. There is not yet any evidence that the intensity or frequency of hurricanes has changed, however.
- Some of Boston’s fastest-growing neighborhoods are also its most vulnerable.
Several waterfront neighborhoods will be especially vulnerable to flooding associated with sea-level rise in the near term, including Downtown, East Boston, Charlestown, and the Seaport area of South Boston. Over the longer term, parts of Dorchester and the South End become increasingly vulnerable as flood waters penetrate inland via the Fort Point Channel and other locations.
- Flooding events will cause significant economic losses.
Sea-level rise will expose 18,000 people and $20 billion of real estate to flooding by about 2030—just 13 years away. Some 85,000 people and $85 billion of property will be exposed by about 2070—based only on what already exists today and not counting future growth and development. Annualized losses from physical damage, displacement, and business interruption are projected to exceed $1 billion by about 2070, unless corrective action is taken.