Martha’s Vineyard is a hot spot — literally.
Early last month, the Washington Post published a climate change report disclosing the fastest-warming states and counties in the nation, with Massachusetts and Dukes County ranked among the highest.
Shaded ruby red on a temperature change map, Martha’s Vineyard, Nantucket, the Elizabeth Islands, and mid- to lower Cape represent some of the fastest-warming regions in the U.S., crossing the 2° Celsuis threshold — a critical point of reference determined in the 2015 Paris accord, where international leaders agreed the earth’s average temperature increases should stay “well below” 2° Celsius to avoid a host of “catastrophic changes,” the Washington Post reported.
Dukes County joins only 71 other counties in the nation to exceed the 2° Celsius mark. So why is Martha’s Vineyard warming so quickly?
Guilty by association
Martha’s Vineyard is part of the Northeast region — the fastest-warming region in the nation. After Alaska, Rhode Island ranks as the fastest-warming U.S. state, followed by New Jersey, Connecticut, Maine, and Massachusetts. Rising temperatures are due in large part to warming winters. In many Northeast states, the average winter temperature from December through February now exceeds 0° Celsius, the temperature at which water freezes. Ponds and lakes aren’t freezing, snow melts quicker, and insects and pests aren’t dying off as they normally would. According to the U.S. Climate Data website, the average temperature in Edgartown in January 2019 was 0.5º Celsius (32.9ºF), and in February 2019, average temperature was 0.7ºC (33.3º F) — above freezing.
The Northeast is also situated where it’s vulnerable to the vagaries of the Gulf Stream — an enormous warm current that travels up the East Coast from the Gulf of Mexico before making a turn toward Greenland and Europe. The Gulf Stream is part of a “global conveyor belt” of currents that transports heat around the world. Martha’s Vineyard and Nantucket are the last, most northerly coastal North American islands that are influenced by the Gulf Stream, according to a 1973 “Looking at the Vineyard” Trustees report. And over the past few decades, scientists have observed a weakening Gulf Stream, which would “affect poleward heat transport, regional climate, and sea level rise along the East Coast,” a recent Real Climate report said.
The Northeast is also experiencing less cloud cover, a result of fewer extratropical cyclones, according to an Advancing Earth and Space science report. Greenhouse gas emissions contribute to weaker cyclone activity, which decreases cloud cover, “giving rise to higher maximum temperature,” the report said.
The 2° Celsius threshold doesn’t always represent “cataclysmic change,” according to the Washington Post article. But it can threaten ecosystems, alter landscapes, and change livelihoods and cultures.
Sea level rise and erosion are of high concern on the Cape and Islands. Sea levels have exceeded the global average by approximately 12 inches since 1900, according to Massachusetts Wildlife Climate Action Tool. The Northeast is especially vulnerable to flooding because of its low-slope coastal areas. Projections suggest the region will experience sea level rise between 8 and 30 inches during the early 2000s, and between 18 and 72 inches by the end of the century. As stated in an August Letter to the Editor, Chappaquiddick’s coast is projected to rise by five feet in 65 to 100 years, and Norton Point, Wasque, and East Beach will become sandbars, as will the acreage from Cape Poge to the Gut, according to National Oceanic and Atmospheric Administration (NOAA) projections.
The Island’s abundance of disease-carrying ticks is another example of how the region’s warming climate is changing the game. Warm weather and greenhouse gas emissions create higher levels of humidity in the atmosphere — a tick’s bread and butter. According to a study, deer ticks die faster when humidity is moderate (75 percent), and survive longer when the humidity is higher (85 to 90 percent). The Northeast is experiencing high levels of humidity, providing an environment conducive for tick survival — and higher incidences of Lyme disease across the region.
Rising temperatures have also made way for the oyster disease dermo. Dermo is a parasite that kills oysters but does not harm people. It originated in the South, and exists along the Gulf Coast. It had a major spread to the Northeast and Martha’s Vineyard in the 1990s during a term of warm weather, “and now it’s here to stay,” said Emma Green-Beach of the Martha’s Vineyard Shellfish Group. Green-Beach completed her master’s research on dermo in the early 2000s. “We haven’t seen any definitive changes in dermo levels in the past couple years, but over time, it will be exacerbated,” Green-Beach said. “[Dermo] likes it hot, and it likes it salty.”
Dermo exists in Edgartown Great Pond, Tisbury Great Pond, and Oyster Pond. “Our great ponds are shallow and sensitive to temperature changes,” Green-Beach said. “As they warm up in the summertime, we could see more dermo. If it’s accompanied by periods of drought, the ponds will get saliter.”
Martha’s Vineyard ponds are also at risk of acidification, according to Green-Beach.
“As waters become more acidic because they’re absorbing carbon dioxide in the atmosphere, the pH in water goes down,” Green-Beach said. “Tiny changes in pH are important.”
Low pH makes if hard to calcify shells to make new shellfish. In an effort to mitigate acidification effects, the M.V. Shellfish group launched a shell recycle program, where they collect shells, let them age until they’re clean, and release them back into Great Ponds for restoration. “Adding shells helps buffer the water in small scales,” Green-Beach said. “It provides hard calcium for baby oysters.”
Oysters are a “keystone species” on Martha’s Vineyard, as their existence provides a habitat for other organisms. “When you have clusters of oysters, they make huge reefs where fish, urchins, crabs, and all sorts of plants and animals can live,” Green-Beach said. “Little fish can hide there. Big fish can hunt there. Oysters create a hard and complex structure on an otherwise muddy, flat bottom.” Oysters also filter water, and adults can filter up to 50 gallons a day, according to Green-Beach.
Algae bloom is another climate-related issue for Martha’s Vineyard ponds, notably Edgartown Great Pond. Algae bloom refers to a rapid increase of algae in freshwater or saltwater ponds that dominates an ecosystem. It becomes dangerous when the algae dies, as it sinks and blankets the bottom of the pond. It is broken down by bacteria which take oxygen out of the pond that many organisms need to survive, according to the Great Pond Foundation website. Algae bloom is often caused by rising nutrient levels, also known as eutrophication. Algae loves hot weather and nutrient-laden stormwater, so as the region sees hotter days and more rainfall, algae bloom could become more present.
Climate change is also changing the landscape for invasive plant species. “Invasive species are thriving and getting a jump on the natives in the spring,” said Suzan Bellincampi, director of Mass Audubon Felix Neck Wildlife Sanctuary. Phragmites, honeysuckle, garlic mustard, and spotted knapweed, among others, are examples of invasive species. “The list goes on,” Bellincampi said. “That is why they are invasive. They take over.” A Smithsonian Magazine article cites how nonnative species are changing their flowering schedule to align with the longer seasons, while ingidenous species are much slower to react to the new conditions.
Bellincampi also touched on how warming waters are impacting aquatic life. “Cold water fish are moving to deeper waters, and species from warmer climates are now moving in to New England waters,” she said. “Locally, we are seeing warmer temperatures in our ponds and increased algae blooms, decreased oxygen due to higher temperatures, and reduction in diversity as organisms can’t tolerate higher temperatures.”
Ocean surface temperatures are warming two to three times faster than the global average, according to a Woods Hole Oceanographic Institution (WHOI) report. The warming, as Bellincampi noted, changes the distribution of multiple species in the U.S. Leatherback sea turtles, for example, migrate to Northeast waters to feed on gelatinous zooplankton. Climate-driven changes in temperature, salinity, and other oceanographic features are likely to affect the distribution of their prey, leading to fewer leatherbacks in the region, according to the WHOI report.
Warming oceans affect shark migration patterns, although great whites, which are most common in the Northeast region, are “less impacted by climate change,” Massachusetts Marine Fisheries shark scientist Gregory Skomal told National Geographic. Unlike other species of sharks, great whites can regulate their own body temperature (are endothermic) instead of moving to warmer or colder waters. But Skomal noted that shark migration routes could be impacted by climate change, as great whites conserve more energy when in warmer waters.
The commonwealth of Massachusetts is considering a $1.3 billion bond issue to provide infrastructure betterment to ward off impending losses due to rising sea levels. The bill would implement the GreenWorks program to help Massachusetts communities address threats of rising sea levels and floodwaters, as well as damage that’s already been done. The bill also includes a grant program that municipalities could apply for each year to fund specific projects — two or more towns could apply jointly, according to the bill.
Martha’s Vineyard also has an Island Climate Action Network (ICAN), a grassroots group that meets throughout the year to discuss, implement action, and create an agenda around climate change. The Martha’s Vineyard Commission, Felix Neck Wildlife Sanctuary, Island Grown Initiative, Vineyard Sustainable Energy Committee, Vineyard Conservation Society, and Vineyard Power are among other Island groups committed to tackling the warming climate.
Martha’s Vineyard tracks coastal oceanographic and meteorological data through the Martha’s Vineyard Coastal Observatory, which is operated by WHOI. The observatory is located a mile offshore of South Beach and provides real-time, archived data.