Jade Cave has lived near the ocean since her family moved to Fiji, a small island in the South Pacific, when she was 6 years old.
“I was raised by a community of people whose history and culture are directly linked to the ocean,” Cave said. “It was a fundamental aspect of the identity of the country that raised me.”
Now 17 and a resident of Cape Town, South Africa, Cave has continued to observe the impacts the ocean has on her life.
“When I look at the ocean…I see coastal communities all over the global South whose lives, cultures, history and existence is held in that water,” Cave said.
But that water is changing.
The average global sea surface temperature increased 0.23 degree Fahrenheit per decade over the past 100 years, according to the National Oceanic and Atmospheric Administration.
Morgan Kelly, a biology professor at Louisiana State University, said ocean warming is caused by two related problems: the ocean absorbs heat from the air, and it absorbs excess carbon dioxide from the atmosphere.
The ocean absorbed over 93% of greenhouse gas emissions since the 1970s, according to the Intergovernmental Panel on Climate Change’s Fifth Assessment Report.
As water warms, it has the potential to disrupt the very balance of ocean life—for both the marine animals who live in the waters and the people who call the shores home.
Excluding mammals that live in the ocean, most marine life is cold-blooded, so the body temperature of marine organisms correlates directly to the temperature of the surrounding water.
“It affects everything,” Kelly said. “Every single process in every single organism is affected by temperature. Every chemical reaction goes faster when the temperatures are warmer.”
That has tangible effects on what’s going on inside the cells of marine animals, Kelly said.
Sometimes it leads to marine organisms burning up energy faster than they can consume food. Other times it leads to marine life eating more food, which can have impacts downstream in the food web.
“When temperatures get to be extreme, at the very high end, what can happen is that really warm temperatures can actually cause the proteins in a cell to break down, and that can be one of the ways that high temperatures can lead to death,” Kelly said.
Warmer water also holds less oxygen. At the same time, marine must consume more oxygen to keep up with accelerated cell processes in warmer temperatures, potentially leading to death.
While Kelly acknowledges that extreme temperatures can lead to death in certain cases, she said many ocean species will experience population shifts or move to more hospitable conditions.
“One of the things that is happening with warming is that we are getting movements of different groups of species that live near the equator toward the poles,” Kelly said.
That means certain warmer water species could see an increase in population and habitat availability.
“Which species are benefited, which species are harmed, really just depends a lot on what its range of temperature tolerances is,” Kelly said. “If you were to study which species are present at any particular location on the coast, what you would find is that some species are increasing and some species are decreasing,” she said.
These changes could spell problems for communities that depend on fisheries as a reliable source of protein and income.
“We have built our cities and our societies and the way we get food around the way the climate used to be,” Kelly said.
According to a 2019 paper published in Science Advances, marine fisheries are crucial food producers that sustain food security, human health and employment worldwide.
The 2019 study said the consequences of climate change can no longer be fully avoided in some areas, like Africa, Asia and Oceania. But if mitigation occurs rapidly, it said, some negative effects could be avoided.
The average global ocean temperature likely will increase by 1.8 to 7.2 degrees Fahrenheit by 2100, according to the IPCC’s 2013 report.
Cave knew she needed to do her part to protect and secure the waters.
She was 16 years old when she founded Ocean Location in 2019, a nonprofit organization to mobilize and educate younger generations to advocate for ocean conservation. She said the organization focuses on three tiers: inform, inspire and activate young people to take action in ocean conservation.
“I feel like when we look at issues like environmental conservation, ocean action and climate change, it’s intimidating,” Cave said. “And we, especially as young people, feel like we’re too small to make a difference, or that the problem is just too huge and insurmountable to ever be solved.”
But Cave said it’s important for young people to remember that they can make a difference, and that they are not fighting alone.
She recognizes the importance of providing tangible and meaningful ways to problem-solve so people her age feel less hopeless against the fight against climate change’s drastic impacts.
Ocean Location provides content and resources relevant to oceans and highlights the work of activists and organizations engaged in the effort to secure the oceans.
Additionally, Cave’s nonprofit posts links to petitions to sign, opportunities to get involved in campaigns and more.
“We live in a time of crisis,” Cave said. “Climate change is threatening not just our oceans, but so much of our lives and future that we can’t afford to have people who want to make change feel like they can’t.”
“The ocean can’t be separated from humanity,” she said. “The climate can’t be separated from humanity.”