Jun 08, 2023 • Annie Cao
Sebastian may have told Ariel, “The human world, it’s a mess/Life under the sea/Is better than anything they’ve got up there,” but climate change has unfortunately taken a toll on the oceans and the creatures that call the sea their home.
In this blog post, we’ll be diving into recent weather events and the consequences of climate change on marine biodiversity.
You may or may not remember learning about El Niño and La Niña in school – for a quick refresher, El Niño warms the surface of the sea, whereas La Niña cools it down. Last year, forecasters predicted that the 2022 winter season would be the third year in a row where the Pacific Ocean would be in a La Niña cycle. Research from the University of Washington suggested that climate change is the cause of these weather patterns.
Normally, winds near the equator push warm water westward from South America to Indonesia. Cold water then rises up to the surface along the coast of South America. When we’re in a La Niña cycle, the winds are stronger, making the water a few degrees colder. This small difference ends up affecting the weather patterns around the world.
In Oceania and Asia, La Niña creates a higher chance of drought, reduced crop yields, less fish stocks for fisherman, and a smaller water supply. In other parts of the biome, such as Indonesia and Australia, they may receive more rain. And in the Southwestern United States, it may be drier than usual, while the deep Tropics deal with a more active hurricane season.
From 2017-2019, there was a sudden jump in the number of juvenile snow crabs – at its peak, there was an estimated 8 billion snow crabs. But by 2021, the population had mysteriously plummeted to around 1 billion, which was a 90 percent decrease. In 2022, Alaskan officials canceled the 2022-2023 Bering Sea snow crab harvest for the first time since the 1990s.
Alaska’s crab fishing industry is worth over $200 million, meaning that many families in the industry will take a hit from this season’s cancellation. Alaska is also the fastest warming state in the US, and every year, their summers and oceans are getting warmer. This means climate change will continue to affect other marine life that calls the Bering Sea their home.
Scientists have come up with a few theories for the unexpected population changes. The warmer waters may have forced snow crabs to migrate further north in search of colder temperatures. But according to an article from TIME Magazine, the rising temperatures may have led to…cannibalism. 😳 Yup, they potentially cannibalized each other. When the water warms up, cold-blooded animals have a faster metabolism and need to consume more food. Combined with the rapid population growth, it’s possible that the snow crabs ran out of their usual food sources and had to resort to cannibalism.
Oceans cover about 70 percent of the earth’s surface. Over 3 billion people rely on fish as a source of protein and an estimated 60 million people work in fisheries and the aquaculture industry. To top it all off, there are around 2 billion people who live in half of the megacities located along the coastline. Oceans do a lot for animals and humans…but are we doing enough to protect them?
As we can see, climate change has created unpredictable consequences. And it doesn’t end there.
Climate change poses an ongoing threat to our oceans and our coastal communities. If it weren’t for oceans, the Earth would already be an uninhabitable place. We need to take better care of the sea to not only protect the marine creatures that live there, but to also protect humanity and future generations.
Cover image via Unsplash (credit: Felipe Portella)