UNITED NATIONS, Sep 11 (IPS) — Human practices, such as unsustainable fishing, pollution, coastal development, and fossil fuel use have pushed the Earth’s oceans to their limits. This has resulted in warmer, more acidic waters. As global temperatures rise yearly due to climate change, oceans continue to see significant losses in biodiversity, rising sea levels, and environmental damage.
"While atmospheric temperatures tend to fluctuate, the ocean is steadily and constantly heating up. The State of the Ocean Report indicates that the ocean is now warming at twice the rate it was twenty years ago", states the United Nations Educational, Cultural, and Scientific Organization (UNESCO) in a 2024 report.
The ocean absorbs the vast majority of the greenhouse gasses emitted globally, causing ocean temperatures to rise at alarming rates. This causes a depletion of oxygen in marine environments, ravaging marine ecosystems.
Biodiversity and ecosystem stability are crucial in ensuring planetary health. Without high levels of biodiversity, access to clean air, food, and water are severely compromised. Warmer waters, as a result of climate change, have made it difficult for a host of species to survive.
The United States Environmental Protection Agency (EPA) states that deoxygenation of waters can lead to hypoxia, or "dead zones", which are environments that cannot sustain marine life. EPA adds that small marine organisms, such as plankton, are particularly sensitive to changes in temperature and oxygen levels. This severely disrupts the food chain as animals further up the food chain face the risk of starvation with their main prey being compromised.
Additionally, deoxygenation and overfishing have led to alarming rates of coral bleaching. Coral reefs are superorganisms that provide the fundamental building blocks for about one quarter of all marine life. They are crucial for ocean health, housing entire ecosystems on their own.
The National Oceanic and Atmospheric Administration (NOAA) stated, "Because of the diversity of life found in the habitats created by corals, reefs are often called the "rainforests of the sea." About 25% of the ocean’s fish depend on healthy coral reefs. Fishes and other organisms shelter, find food, reproduce, and rear their young in the many nooks and crannies formed by corals".
Coral bleaching is particularly concerning as reefs rarely recover after they’ve been degraded. As a multitude of ecosystems are dependent on coral reefs for survival, ensuring proper coral health is imperative for biodiversity.
Rising temperatures caused by the greenhouse effect have led to ocean waters becoming significantly more acidic over the years. According to EPA, ocean waters have increased in acidity by over 25 percent since the Industrial Revolution.
Acidity has a significant, adverse impact on a multitude of marine animals. According to the Natural Resources Defense Council (NRDC), rising levels of pH, which contribute to acidity, impede the availability of carbonate, which allows mollusks to create shells and other important structures. This worsens the chances that mollusks have at survival and puts their predators at risk of starvation.
Losses in ocean biodiversity pose serious concerns in humans as well. According to the World Bank, approximately 58 percent of the world’s income comes from jobs in fish production. Additionally, over 3 billion people rely on fish as a crucial part of their diets. Decreasing levels of biodiversity in the Earth’s oceans threatens to cause widespread food insecurity.
Coastal communities, so far, have been the most directly impacted by worsening ocean health. Rising sea temperatures have exacerbated the rise of sea levels and flooding. According to the EPA, exposure to sea water gives way to increased risks of contracting waterborne diseases. Additionally, coastal flooding causes great damage to critical infrastructures, such as housing, roads, and salination systems.
IPS UN Bureau Report