The use of fossil fuels has become commonplace over the past few decades. Although these fuels facilitate many aspects of our daily lives, their use has a significant side effect: the release of carbon dioxide (CO2) into the atmosphere. Since 1980, CO2 levels have increased by more than 40%, which has accelerated the phenomenon of global warming. This reality has profound implications for our planet, with the oceans being one of the most affected environments.
The oceans absorb more than 90% of all heat associated with global warming, a fact that not only influences water temperature, but also has devastating consequences for marine life and aquatic ecosystems, as explained in this article.
A remarkable study, published in the journal 'Science Advances', reveals that Ocean warming is 13% greater than expected and continues to accelerateThis conclusion was reached using the Argo flotation system, which consists of floats that autonomously submerge and emerge in the ocean to collect temperature data at depths of up to 2000 meters. Once these floats surface, they transmit the data wirelessly to satellites for further analysis.
By comparing direct temperature measurements with data generated from computer models, researchers found that the 1992 warming rate is nearly double that recorded in 1960. This indicates that Ocean warming has been accelerating in recent years, as detailed in This analysis on sea level.
Research indicates that the oceans of the Southern Hemisphere have experienced considerable warming, while the Atlantic and Indian Oceans have begun to notice this increase, especially in recent years. It is evident that With the rise in temperature, virtually all regions of the planet will be affected..
The consequences of ocean warming are visible and worrying. For example, Coral reefs are suffering from severe bleaching episodes, The krill population has decreased by more than 80%, and Some species such as jellyfish have begun to proliferate.
The full study is available here (In English).
Ocean Heat: A Global Problem
1955 from the ninety percent Global warming has been concentrated in the oceans. Data show a progressive increase in the internal heat of the water, which is causing thermal expansion and contributing to sea level rise. In this regard, it is estimated that ocean warming is responsible for between one-third and one-half of global sea level rise. Furthermore, the state of the oceans is related to the melting of Greenland, which is affecting your balance.
Most of the additional energy accumulates in the surface layers of water, at depths between 0 and 700 meters. The last ten years have undoubtedly been the warmest decade in the known history of the oceans, and 2023 has set a new temperature record..
The weakening of the oceans' ability to absorb heat could have devastating consequences. For example, rising ocean temperatures also fuel extreme weather events, such as more intense hurricanes, which feed on heat from the ocean surface. This additional warming also affects the distribution of marine species, many of which migrate to cooler waters due to changes in their habitat; topics discussed in research on atmospheric particles.
Marine Heat Waves and Their Consequences
Marine heatwaves are increasing in frequency, intensity, and duration. A report by the Intergovernmental Panel on Climate Change (IPCC) notes that human influence has been a driving factor in this increase in ocean temperatures since the 70s. Between 2006 and 2015, most marine heatwaves were devastating, causing coral bleaching and reef degradation across large areas.
In 2021, it was documented that close to 60% of the world's ocean surface has experienced at least one episode of marine heatwaves. This bleaching occurs when thermal stress causes corals to expel the microscopic algae that are essential for their survival. This phenomenon is exacerbated by rising temperatures, as explained in a study on Hawaiian corals.
Abnormal water temperatures can be catastrophic for marine ecosystems. Forecasts suggest that, without significant action, all coral reefs could suffer mass bleaching by the end of this century. A warming of 1,5°C is expected to destroy between 70% and 90% of coral reefs, while a 2°C increase could result in almost total losses.
In addition to these direct effects, ocean warming alters ocean currents, increases water stratification, and reduces carbon solubility, which impacts the ocean's ability to absorb CO2 from the air. This can create a feedback loop where additional warming leads to more greenhouse gas emissions, as explained in the links between extreme weather and global warming.
Impacts on Sea Level and Ecosystems
The oceans are at the center of the discussion on climate change, since around the 90% of the excess heat generated by global warming is stored in them. This is crucial, as the accumulated heat causes the waters to expand, resulting in a rise in sea level that puts many coastal communities around the world at risk. An increase that also affects the Arctic oceans.
The World Meteorological Organization has warned that ocean warming and the resulting rise in sea levels could have irreversible impacts. In this process, the Pacific islands are estimated to be on the "front lines" of this crisis, facing the risk of flooding, tropical cyclones, and other climate-related disasters.
- Rising sea levels threaten coastal cities and vulnerable ecosystems.
- Phenomena such as ice melt cycles in Greenland and Antarctica are contributing to this increase.
- Marine heat waves increase the intensity of extreme weather events.
- Coral bleaching and ocean acidification are affecting marine biodiversity.
Studies have shown that as ocean warming continues, the effects translate not only into changes in aquatic biodiversity, but also in human well-being. Fisheries, tourism, and local economies that depend on the health of marine ecosystems face significant risks, which is related to the dangers of overfishing and global warming.
As 2024 approaches, ocean temperatures are projected to continue to exceed historical records, potentially exacerbating extreme weather events across the globe. This includes more powerful hurricanes and significant shifts in rainfall patterns, impacting freshwater supplies and threatening food security in many vulnerable regions.
Ocean warming should not be viewed as an isolated phenomenon; it is part of an interconnected climate system affecting the entire Earth. Understanding these processes is critical to developing effective solutions to mitigate the effects of climate change, as detailed in strategies to stop global warming and protect both marine ecosystems and the communities that depend on them.
