Sunday, April 3, 2022

New NOAA Climate Projections Forecast Increase in Southern New England Flooding

The question for us is what we're going to do about it

By Frank Carini / ecoRI News staff

Setups like this one on the coast of South Kingstown, R.I., will do little to impede the sea’s advancement during the next three decades (Frank Carini/ecoRI News)

The climate crisis has taken root. The United Nations’ latest climate report explains how deep this worldwide problem is embedded.

Closer to home, another report published last month is equally alarming, for the present and future of southern New England. The National Oceanic and Atmospheric Administration’s 2022 Sea Level Rise Technical Report warns that the United States will see as much sea-level rise, about a foot, in the next three decades as it did during the entire previous century.

Rhode Island, Massachusetts and Connecticut, like much of the rest of the Atlantic Coast, is a sea level-rise hot spot. The National Aeronautics and Space Administration notes that every inch of sea-level rise results in the loss of about 100 inches (8.3 feet) of beach. Locally, sea levels have already risen nearly a foot since the 1930s.

Thirty years, the length of a standard mortgage, is not a long time in the scope of hundreds or even thousands of years often referenced in climate research. But both February reports feature an abundance of detailed scientific information that can no longer be ignored.


Strategies to address sea-level rise include doing nothing;
protect with seawalls, levees and other hardened structures; accommodate
by elevating structures; advance by building a buffer out into the ocean;
retreat by moving away from the coast; and retreat with ecosystem-
based adaptation that reintroduces natural systems. (NRDC)

The U.N.’s Intergovernmental Panel on Climate Change (IPCC) report, Climate Change 2022: Impacts, Adaptation and Vulnerability, describes the planet’s present and future in definitive statements.

“Climate change has already had diverse adverse impacts on human systems, including on water security and food production, health and well-being, and cities, settlements and infrastructure.”

The 3,675-page report is the most detailed look yet at the threats posed by global warming. It concludes that nations are not doing enough to protect cities, coastlines, farmland and infrastructure from the hazards of a changing climate, nor are they doing enough to mitigate future impacts.

The dangers of the climate crisis are mounting so rapidly that they could soon overwhelm the ability of both nature and humanity to adapt unless greenhouse gas emissions are quickly reduced, according to the IPCC report.

Written by 270 researchers from 67 countries, the report is “an atlas of human suffering and a damning indictment of failed climate leadership,” according to António Guterres, the United Nations secretary general. “With fact upon fact, this report reveals how people and the planet are getting clobbered by climate change.”

The multi-agency NOAA report offers projections out to the year 2150 and information to help municipalities assess potential changes in average tide heights and height-specific threshold frequencies as they strive to adapt to sea-level rise.

“For businesses along the coast, knowing what to expect and how to plan for the future is critical,” said U.S. Secretary of Commerce Gina Raimondo in announcing the NOAA report. “These updated projections will help businesses, and the communities they support, understand risks and make smart investments in the years ahead.”

Raimondo, the former governor of Rhode Island who pushed hard for the construction of a fossil fuel power plant in the woods of Burrillville, was the first government official quoted in the Feb. 15 press release, even before the national climate advisor and the NOAA administrator.

One of the most striking findings of the NOAA report is that sea level along the contiguous U.S. coastline is projected to rise 10 to 12 inches on average between now and 2050, marking the same level of increase that occurred between 1920 and 2020. The report suggests there could be an additional 1 to 5 feet of sea-level rise by 2100.

With the exception of the Gulf Coast, NOAA models project those living and working along the East Coast will experience much higher sea levels, because of a combination of factors such as geological forces, the shifting of tectonic plates and the spin of the Earth.

This rise in ocean waters will bring with it more frequent and damaging floods, according to the 111-page report. By 2050, the increase in tide and storm-surge heights will cause a major shift in coastal flood regimes. Buildings, homes, roads, substations and critical infrastructure will need to relocate to higher ground.

In 30 years, the report notes, moderate flooding is expected to occur, on average, more than 10 times as often as it does now. Major flooding events, described as “destructive,” will occur about five times more frequently.

Salt water will infiltrate groundwater and freshwater bodies more frequently, damaging private septic systems and drinking water supplies. Coastal wetlands will drown, destroying vital wildlife habitat and removing natural storm buffers.

Schematic showing physical factors affecting coastal flood exposure. Due to the combination of sea-level rise and sinking lands, the probability of flooding and associated impacts are increasing along most U.S. coastlines. (NOAA)