Ocean warming and acidification is a damaging element of global warming. The Gulf of Maine is warming at a rate faster than ninety-nine percent of Earth’s oceans. This change in climate is negatively affecting the ecosystem of fisheries in New England, particularly in Maine. It is expected that due to ocean warming the Gulf of Maine will lose significant aquatic species that have shaped Maine’s economic and cultural success for centuries. There will need to be sustainability efforts to protect ocean life and the Maine economy. A sustainable economy will create a resilient, ecologically friendly and steady-state market. This paper evaluates the causation of severe ocean warming in the Gulf of Maine and emphasizes the major ecological and economic consequences that will need to be mitigated.
The Gulf of Maine is a “C” shaped gulf that restricts water movement as it is not a free-flowing water system. It stretches from Cape Cod to Nova Scotia. It is also located at a meeting point of two major currents in the Atlantic Ocean. The Labrador Current travels southward from the East Coast of Greenland. The cold water from the current sinks deeper along the coast of Eastern North America. The Labrador Current is responsible for keeping the Gulf of Maine’s cold-water ecosystem sustained with cooler, deep water fluxes. However, the Labrador meets an opposing current, the Gulf Stream. The Gulf Stream flows from the equator to the Arctic in a circular motion. These currents cross paths at the Gulf of Maine, with the Labrador Current’s extreme cool depths being deposited into the Gulf. However, the melting of Arctic ice from Greenland has caused an influx in freshwater to the Labrador Current. Freshwater is not as dense as saltwater and therefore does not sink the way saltwater does. As a result, the Labrador Current is not flowing as much cool water into the Gulf of Maine. Ocean circulation patterns in this region are being altered because of this. Fluxes of warm-water from the Gulf Stream are now entering and distorting the cold-water ecosystem. This abrupt change in current circulations as a result of climate change is posing a threat to ecosystems that are dependent on cool water. Because of these factors, the Gulf of Maine is warming at an alarming rate of seven times faster than the rest of the global oceans (Poppick, 2018).
The ecosystem is in flux, and can be considered in a marine heat wave. Over the past three decades, the Gulf of Maine has warmed by 0.06℃ per year. For better understanding, this means that this region has increased temperature by 1.8℃ in the past thirty years. This is a drastic temperature change for an ecosystem to experience. The data on temperature anomalies can help further emphasize the urgency of this warming. In oceanography, marine heat waves are defined as “periods when water temperature rises above the 90th percentile (of average temperatures) for more than five days”. Data from 2018 shows that the Gulf of Maine experienced more than 180 days over the 90th percentile. Researchers from the Gulf of Maine Research Institute reported that there were 10 daily temperature records set in the summer of 2018, as well as 18 days in the corresponding winter (Carlowicz, 2018). These numbers have likely grown over the last four years since the data was collected.
Another cause for concern in this region is the absorption of carbon dioxide into the Gulf of Maine. Global oceans are absorbing carbon dioxide from manmade atmosphere pollutants such as coal, fossil fuels and oil. The input of carbon dioxide is changing the chemistry of the ocean as it is transformed to carbonic acid, shifting the water’s pH to be more acidic. Warmer sea water does not dissolve and absorb carbon dioxide as effectively as cold sea water. Therefore, warm waters experience a greater change in water pH balance (Siedlecki et al., 2021). This makes the Gulf of Maine substantially more vulnerable to ocean acidification as the water temperature increases. As a feedback loop, there is a positive relationship between atmospheric emissions and ocean acidification. As society continues to emit carbon into the atmosphere, the oceans will continue to acidify, further damaging oceanic ecosystems. The system is out of control and unable to self-stabilize, on the tipping point of creating a new system entirely. This feedback loop is dangerous for the species of the Gulf of Maine.
There are a variety of species being impacted by ocean acidification including staples of Maine fisheries. These species include lobster, shellfish, shrimp, and ground fish such as mackerel, cod and herring. The change in the Gulf of Maine water temperature is driving these species North to cooler water. As of 2018, the annual value of overall Maine commercially harvested marine resources was $637,174,944 (Department of Marine Resources, 2019). This is one of the highest annual values in Maine history. As prior years have proved to be economic “booms” for Maine fisheries, it is expected that an unprecedentedly large “bust” is to come. This is both a result of economic patterns and the upcoming consequences of ocean warming and acidification on the key species for Maine fisheries.
Shellfish are an economic backbone to Maine fisheries. The impact of ocean acidification is detrimental to the shellfish population in the Gulf of Maine. Species such as mussels, scallops, oysters, and clams will be affected by acidic waters as they cannot formulate their hard shells in such conditions. Without proper shelling, natural threats such as predators and disease threaten shellfish survival. Shellfish exposed to increasing rates of carbonic acid and other pollutants are also an inorganic choice for consumers, possibly decreasing demand for Maine shellfish in future years (Climate Change Threatens Maine’s Fisheries, 2022). Many ocean front places in Maine such as the Penobscot Bay region rely on shellfish as a dominant source for their local economies. For example, the harvesting of softshell clam flats provided an annual value of $12,854,545 in 2018 for the Maine economy. Scallops earned Maine $5,935,639 in 2018 as well (Department of Marine Resources, 2019). Acting as the fourth and sixth most valuable marine resource industries, shellfish are critical to the Maine economy. Many researchers are concerned on how to mitigate the threat that future ocean acidification will hold on the Maine shellfish market.
Another important species in this region is cod. Due to negligence from commercial fishing in regards to ocean warming, cod have been severely overfished. With the current conditions of the ecosystem, it is unlikely that cod can replenish their stock as the “spawning stock biomass that produces the maximum sustainable yield has been declining steadily since 2002 rather than remaining constant.” (Pershing et al., 2015) The added impact of societal ecosystem services abuse may cause future endangerment of cod in the Gulf of Maine.
Maine lobster is a delicacy. For the past decade or so, Maine lobster has accounted for an average of 80% of American lobster harvesting. It also accumulated a value of $484,543,633 in 2018 (Department of Marine Resources, 2019). Lobster is the largest marine industry in Maine that accumulates the greatest wealth for the Maine economy. It is notable that Maine lobster’s price per pound has changed over the last few decades. This is mostly due to increasing policies in place to make a safer, environmentally friendly lobster fishing industry. However, the Maine lobster market will reach an expiration date due to ocean warming and acidification. As it is a growing and dependent industry for Maine, the state economy will suffer the results of a Gilded Trap, as the ecological consequences will overpower the political and economic efforts towards sustaining lobsters. The Gilded Trap is an economic concept best defined as “a type of social trap in which collective actions resulting from economically attractive opportunities outweigh concerns over associated social and ecological risks or consequences.” (Steneck et al., 2011) Since 1985, income derived from lobsters in Maine has increased by 400%. This data is corrected for inflation. Although this is considered an economic success in the capitalist system, is it sustainable? The negative impact of ocean warming in Southern New England ocean regions has led to a “70% decline in lobster abundance” (Steneck et al., 2011). It is inevitable that this collapse will occur as the Gulf of Maine continues to warm and acidify.
There are many factors controlling the future of the Maine lobster industry. As water warms, predatory fish and shell disease become a larger issue. Lobsters depend on cold water ecosystems. The influx of warm Gulf Stream water is forcing the lobsters to move offshore or migrate north to find colder waters. These migrations are necessary for lobsters, as the prey they hunt are also leaving the warming Gulf of Maine for a cooler ecosystem. For example, the decrease in groundfish such as herring will affect the lobster industry. Herring is used for effective lobster bait. As herring migrate and become scarce to Gulf of Maine fisheries, the price of herring is driven upwards (Marine Stewardship Council, 2022). The Maine lobster population and industry is not resilient to the impacts of climate change on the Gulf of Maine ecosystem and food chain. It is a great sustainability concern that the state of Maine’s prized lobster industry will suffer tremendously in the upcoming generations.
In conclusion, the reciprocal feedback system at work in the Gulf of Maine is hurting the ecosystem and economy. Human pollution on complex environmental systems has created a positive relationship that is destabilizing the Gulf of Maine and marine economies. Increasing carbon dioxide emissions from human activities have caused Greenland ice sheets to melt and change the current circulation in the North East Atlantic. The high atmospheric levels of carbon have also resulted in more ocean absorption of carbon dioxide. Both of these factors have caused ocean warming and acidification. Marine life has had to migrate or suffer due to the change in temperature. As these resources become scarce, the Maine fishing industry will take a toll, resulting in negative economic and cultural impact. Society will continue to release atmospheric pollution while these implications worsen. Mitigation efforts to help create a sustainable relationship between the economy and environment are needed. The changes the Gulf of Maine is facing are due to global warming. Local policies will be needed to mitigate the industrial and ecological damage. However, in order for the ecosystem and economy to be resilient and protected from climate change, the world needs to proactively increase its sustainability efforts by limiting carbon emissions.
Sources:
Carlowicz, M., 2018. Watery heatwave cooks the Gulf of Maine – Climate Change: Vital Signs of the Planet. [online] Climate Change: Vital Signs of the Planet. [Accessed 9 February 2022]. This source comes from NASA’s Earth Observatory, Global Climate Change website.
Maine.gov. 2019. Department of Marine Resources. [online] [Accessed 9 February 2022]. This report was released by the Department of Marine Resources on Maine.gov with credits from InformME. The report intends to show the major increases and “boom” happening in marine fishery industries in 2018. The goal is to share the success that the economy is experiencing because of the fishing industry under the Maine government.
Marine Stewardship Council. US & Canada – English. 2022. Climate change and fishing. [online] [Accessed 9 February 2022].
Natural Resources Council of Maine. 2022. Climate Change Threatens Maine’s Fisheries. [online] [Accessed 9 February 2022].
Pershing, A., Alexander, M., Hernandez, C., Kerr, L., Le Bris, A., Mills, K., Nye, J., Record, N., Scannell, H., Scott, J., Sherwood, G. and Thomas, A., 2015. Slow adaptation in the face of rapid warming leads to collapse of the Gulf of Maine cod fishery. Science, 350(6262), pp.809-812.
Poppick, L., 2018. Why Is the Gulf of Maine Warming Faster Than 99% of the Ocean? – Eos. [online] AGU, EOS. [Accessed 9 February 2022].
Siedlecki, S., Salisbury, J., Gledhill, D., Bastidas, C., Meseck, S., McGarry, K., Hunt, C., Alexander, M., Lavoie, D., Wang, Z., Scott, J., Brady, D., Mlsna, I., Azetsu-Scott, K., Liberti, C., Melrose, D., White, M., Pershing, A., Vandemark, D., Townsend, D., Chen, C., Mook, W. and Morrison, R., 2021. Projecting ocean acidification impacts for the Gulf of Maine to 2050. Elementa: Science of the Anthropocene, 9(1).
STENECK, R., HUGHES, T., CINNER, J., ADGER, W., ARNOLD, S., BERKES, F., BOUDREAU, S., BROWN, K., FOLKE, C., GUNDERSON, L., OLSSON, P., SCHEFFER, M., STEPHENSON, E., WALKER, B., WILSON, J. and WORM, B., 2011. Creation of a Gilded Trap by the High Economic Value of the Maine Lobster Fishery. Conservation Biology, 25(5), pp.904-912.