An Ocean Warming: Sea Level Rise

In a previous post, we explored changing ocean chemistry through the phenomenon known as ocean acidification, and the effects of it on the people and species that call the Gulf of Maine home.

However, there is another important piece of the puzzle. As ocean water becomes warmer and more acidic, it expands and swells. This increase in volume, combined with fast-melting arctic sea and land ice, causes substantial changes in sea level – which can wreak havoc on our coastlines.

Numerous studies have shown that the East Coast, ranging from North Carolina to the Gulf of Maine, is experiencing this phenomenon, known widely as sea level rise, at a rate three to four times faster than the global average. In fact, researchers refer to the region as a “unique 1,000-kilometer-long hotspot” where the impacts will be “disproportionately felt.” For New England especially, sea level rise spells trouble because of the vulnerability of our coastal cities, utilities, and infrastructure – not to mention our strong dependence on our coastal economies.

Unquestionably, the threat of sea level rise demands our attention because frankly, this isn’t an issue to be discussed and acted upon at some point in the future – it is happening now.

Signs of sea level rise, including incidences of “sunny-day flooding” and storm surges, have shown that the threat is real and imminent. In 2012, when Hurricane Sandy ravaged the coasts of New Jersey and New York, we saw the massive destruction that sea level rise and strengthened storm surges can have on a city.

Fortunately, Boston missed the brunt of the storm, but having seen its impacts, it’s clear that Boston cannot wait until it is too late or until a disaster like super-storm Sandy strikes to begin planning.

It is paramount that we have the necessary groundwork laid out so Boston, and New England at large, is able to adapt to the issue. Through the creation and implementation of forward-thinking policies, the consequences of sea level rise can be lessened. In most cases, with adequate energy and resources devoted to the issue, we will be able to anticipate some of what is to come and preemptively address the areas in which attention is immediately needed.

Some research and planning is already happening. Sea Change Boston has an interactive map which shows a variety of possible scenarios for what Boston might look like – and which areas might be underwater – depending upon the incidence of major storms over time. This map is based upon projections that global sea levels are projected to rise 1-2 feet by 2050. And the Boston Harbor Association put together additional maps showing the impacts of sea level rise to Boston and the surrounding areas if the sea level rises 2.5 feet, 5 feet, or 7.5 feet.

With the Gulf of Maine warming at a rate faster than 99 percent of other ocean areas, we in New England must be prepared with policies focusing on protection, adaptation, and/or accommodation to sea level rise, all of which will be critical in shaping how we respond to this imminent threat. It is only a matter of time before a rising sea level will begin impacting our infrastructure, transportation, and even our safety.

 

 

An Ocean Warming: Ocean Acidification, Lobster, and the Need for More Research

Year after year, temperatures in the Gulf of Maine’s waters have risen at unprecedented rates, a result of the same increased concentrations of atmospheric greenhouse gases (primarily carbon dioxide derived from human activity) responsible for climate change.

This has caused a slew of problems for the marine life in the area – and it also means serious trouble for the ocean’s biogeochemical composition. The ocean has always served as Earth’s largest “carbon sink,” meaning that naturally occurring and industrially produced carbon dioxide is dissolved into seawater and, through a chemical synthesis process, forms carbonic acid.

Carbonic acid breaks down into ions that increase the ocean’s acidity. Over time, marine species have evolved alongside this process in a steady transformation leading to a balanced pH for the ocean.

But, as humans have deepened their addiction to climate-warming fossil fuels, more and more carbon dioxide is being pumped into the atmosphere – meaning the ocean is taking on more carbon dioxide than ever before. These drastic increases change the ocean’s pH level, throwing it off balance and making it more acidic.

Learning as we go

The full effects of ocean acidification are not yet entirely known, but we have begun to see its effects on certain species. The group of species most threatened by ocean acidification are some of the most important to New England’s coastal economy: the ‘calcifiers’ – lobsters, scallops, oysters and other fish that use the carbonate and calcium ions dissolved in seawater to build their shells.

As the water becomes more and more acidic, it becomes harder to for these species to make and maintain their shells. And as they devote more energy to constructing their shells, less energy can be given to other essential processes, like eating or reproduction.

An uptick in shell disease threatens the fishery

For the American Lobster, ocean acidification has been shown to have devastating effects on the growth and shell building rates of juveniles, making them significantly more susceptible to threats like predation and disease.

A shell disease that creates unsightly lesions in the lobster’s hard exoskeleton, for example, had previously been thwarted by colder water temperatures. But that disease has now slowly begun to creep its way up the coast and into the Gulf of Maine. Given the increasing vulnerability of lobsters, and juveniles in particular, this shell disease and other threats have the potential to inflict serious harm on the species, the fishery, and New England’s economy as a whole.

A Lesson in Taking Initiative

The threats facing our oceans due to ocean acidification have prompted several states to take the initiative to begin to address the regional impacts of coastal and ocean acidification. This spring, Massachusetts senators and representatives are working on a bill that will create a special commission to examine the existing and potential effects of ocean acidification on both ecologically and economically important species in the waters off of Massachusetts.

This bill, Resolve H. 716, follows a rough framework laid out by states like Washington and Maine who have already approved commissions to confront the threats of ocean acidification.

In a recent roundtable forum, Massachusetts Congressman Bill Keating emphasized that thorough research on ocean acidification is critical because without the best scientific knowledge, it is impossible to know how Massachusetts should take action.

Following in Washington’s footsteps is an excellent starting point for this work, however the situation facing Massachusetts and Maine (and New England at large) is unique. In the Gulf of Maine, scientists are witnessing changes in temperature and pH more rapidly and dramatically than almost anywhere else in the world – and its waters face a unique stressor due to the arctic ice melt and the resulting influx of freshwater. On top of the environmental factors, New England is especially vulnerable due to its economic dependence on susceptible species such as lobster.

Next Steps

There’s no question that establishing a devoted task force to study ocean acidification and what it means for the people and species in Massachusetts and New England will be helpful. With the support of strong science and the engaged voices of all stakeholders, addressing New England’s unique ocean acidification challenges is an important step in addressing climate change in our region.

An Ocean Warming: Atlantic Cod and Northern Shrimp Search for Colder Water

Perhaps no other New England species has felt the effects of the Gulf of Maine’s rapid warming like the fabled Gulf of Maine cod. An iconic species since its discovery centuries ago off of New England’s coast, cod profoundly impacted the way our region developed, and has shaped our coastal economies.

Today, however, the state of the species looks much different, with cod stocks in the Gulf of Maine hovering around three percent of what scientists say are sustainable levels. In an attempt to quell the overfishing of cod, restrictions on fishing quotas have been enacted. However, instead of seeing the cod stocks rebound, the numbers have continued to plummet.

There are two reasons for this: First, continued fishing pressure hasn’t allowed for enough of an opportunity for cod populations to recover. The other reason? You guessed it: drastic warming due to climate change.

Cod’s home is no longer the comfort zone

Climate change has led to warming ecosystems all over the world, but the Gulf of Maine is experiencing this warming trend faster than most. Cod, like every species, has a range of temperatures at which they can live comfortably, which in turn makes a range of geographical areas suitable for them. Historically, the Gulf of Maine has been at the southern boundary of their range. But, with Gulf temperatures rising due to climate change, cod are now starting to move north in search of cooler temperatures.

Because of this shift, restrictions on fishing quotas, even if effective on their own, have failed – as they didn’t account for what would happen due to warming waters.

As scientists and fishery managers have begun digesting this information and its implications, they are increasingly calling for something called “ecosystem-based management,” a management principle that considers the environmental factors in play in a given ecosystem. With widespread use, this broader understanding of what’s happening, and why, could provide a brighter outlook for the future of Gulf of Maine cod.

Northern shrimp headed further north

Another Gulf of Maine species, northern shrimp (pandalus borealis), face a similar situation. This small crustacean is an integral part of the Gulf of Maine food web. It’s unique because it is hermaphroditic, meaning the shrimp first mature as males at around two and a half years of age, and then about a year later develop into females. Northern shrimp feed on plankton and benthic invertebrates, and are then prey for several important species of fish, including cod, redfish, and hake.

For decades, the northern shrimp fishery thrived, until a few years ago, when stocks showed massive declines and low levels of shrimp reaching the age when they’re large enough to be fished. Particularly warm water temperatures during what is known as the “ocean heat wave” of 2012 caused stocks in the Gulf of Maine to drop even more dramatically. Although heavy fishing pressure is partly to blame for the driving the stocks down, scientists also point to the shockingly low levels of fishable shrimp. As the northern shrimp’s lifecycle is highly dependent on temperature fluctuations – with colder temperatures producing higher levels of fishable shrimp – the decline can be linked to warmer waters.

Northern shrimp, like cod, have a narrow range of temperatures in which they can thrive and, similarly, the Gulf of Maine is at the southern end of their range.

Long-term fishery closure a warning sign

Since 2013, the northern shrimp fishing seasons have been closed entirely. With ocean temperatures predicted to continue their warming trend and the species’ already vulnerable status, it looks increasingly bleak for the fishery.

Little by little, we are losing cod and shrimp to colder waters, and others soon may follow. It’s clear the Gulf of Maine and its composition is changing. That’s why plans to mitigate climate change must pay close attention to oceans and the warning signs they’re giving. And in the meantime, fishery managers must do everything within their power to ensure that management strategies incorporate the best climate science possible.

 

 

An Ocean Warming: Climate Change in the Gulf of Maine

The effects of climate change can be seen all over the world – whether it’s the severe droughts in California, rapid sea-level rise in the Indo-Pacific, or stronger storm systems, the effects of anthropogenic (human-caused) climate change are seemingly everywhere, and the Gulf of Maine is no exception.

Multiple studies have recently shown that the Gulf of Maine, like most of our planet’s oceans, is warming. However, what sets the Gulf of Maine apart is the alarming rate at which this warming is occurring: Scientists say the Gulf of Maine is warming faster than 99 percent of the world’s oceans.

Granted, the Gulf of Maine has been warming for some time, with a steady rate of about 0.05 degrees per year from 1982 to 2004. But we’re now seeing a substantially accelerated rate in warming, about ten times faster than that – warming by approximately a half-degree per year!

How does climate change impact the Gulf of Maine?

Although scientists are still speculating on the explanation for these accelerated warming trends, there is no question about their negative effects.

  • Countless fish stocks have shifted northwards in search of colder temperatures, leaving fisheries struggling in their absence. And as these species migrate out of the Gulf of Maine, other fish, marine mammals, and seabirds that rely on them for food are now left scrambling, in some instances, to avoid starvation. The Atlantic Puffin, for example, once a critically endangered seabird, is now facing a new challenge: species such as white hake and Atlantic herring – both essential elements in the diets for puffin hatchlings – are seeing a shift in geographical range as they move to colder and deeper waters.
  • Diseases that were never before present in the Gulf of Maine have now carved out their place and threaten species. An epizootic shell disease that plagued southern New England waters for years is now cropping up in the Gulf of Maine and poses a serious danger for crustaceans – primarily the American lobster.
  • Non-native and invasive species like green crabs, longfin squid, and black sea bass have been able to move their way up the coast and into the Gulf of Maine, throwing the delicate balance of the entire ecosystem out of sync.
  • Our coasts are under threat from sea-level rise due to changes in density: As water gets warmer, it expands, presenting small towns and major cities alike with an entirely new set of challenges for the future.
  • And the very chemistry of the Gulf of Maine is transforming. Salinity and acidity levels are changing due to increases in precipitation, the rapid melting of Arctic ice, and the rising levels of atmospheric carbon dioxide and other greenhouse gases.

Chemistry? Sea-level rise? Invasive species? If this all sounds overwhelming, you’re not alone. That’s why we’re introducing this blog series, An Ocean Warming, to explore the impacts of climate change in the Gulf of Maine on the species, industries, and people that depend on its health.

Through regular posts focusing on different aspects of this complex issue, we hope to share insights on what the future and fate of the Gulf of Maine will look like – and how we can understand, mitigate, and adapt to this new reality.

 

WATCH: What is Marine Debris?

Check out this wonderful “cartoon crash course” on marine debris from The Pew Charitable Trusts and cartoonist Jim Toomey.

A problem of massive scale and with disastrous effects, marine debris is an issue that demands our attention. Ranging from plastic bottles to sunken ships, discarded fishing gear, and your windswept sun hat, NOAA defines marine debris as “any persistent solid material that is manufactured or processed and directly or indirectly, intentionally or unintentionally, disposed of or abandoned into the marine environment.”

Marine debris is a universal issue: it is found in every ocean on earth, including here in New England, where we are already facing threats from climate change, overfishing, and more.

Marine debris threatens marine life, impacts navigational safety, and hurts the economy and human health. Importantly, however, marine debris is preventable. Watch the fun video to learn more about marine debris and what you can do to help!