UNESCO Warns of Severe Climate Change Impact on Oceans

Climate change has a serious impact on the state of the oceans, leading to rising sea levels, acidification, and loss of biodiversity, among other problems, warns UNESCO. The UNESCO State of the Ocean Report 2024 highlights urgent threats to marine ecosystems and coastal communities worldwide.

UNESCO’s study, published in early June, reveals new and alarming data about the threats facing the ocean. The research, involving more than 100 scientists from 30 countries, indicates that the rate of ocean warming has doubled in the last twenty years, an alarming trend given that while atmospheric temperatures tend to fluctuate, ocean temperatures increase consistently and steadily.

The report notes that although the international commitments of the 2015 Paris Agreement aim to limit global warming to less than 2°C above pre-industrial levels, ocean temperatures have already increased by an average of 1.45°C globally. It also identifies regions where temperatures exceed 2°C, such as the Mediterranean, the Tropical Atlantic Ocean, and the Southern Ocean.

A clear consequence of ocean warming is the global rise in sea levels, which has doubled in the last 30 years, totaling 9 cm. This phenomenon endangers millions of people worldwide living in coastal areas. In Mexico, some municipalities in the Yucatan Peninsula, half of Chiapas, and most of Tabasco are highly exposed to these changes, as highlighted by the International Habitat Coalition in their report Internal Displacement Due to Megaprojects, Changes in Productive Processes, Environmental Impacts, and Climate Change in Mexico. According to a World Bank study cited in the report, there could be 3.1 million climate-displaced people in Mexico by 2050. 

UNESCO also emphasized that more than 500 dead zones have been identified in the oceans due to oxygen loss caused by warming and pollution. The world's second-largest dead zone is in the Gulf of Mexico at the mouth of the Mississippi River, where chemical fertilizers used in agriculture are discharged. This directly impacts the survival of thousands of marine organisms and the fishing communities that depend on them for their livelihoods. In Mexico, more than 106,000 workers were employed in the fishing industry in 1Q23, according to the Ministry of Economy.

Increased ocean acidity is also a major concern. The sea absorbs 25-30% of fossil fuel emissions released into the atmosphere, causing changes in the ocean's chemical composition, the study underscores. This affects thousands of coastal species essential for the functioning of marine ecosystems and human well-being, such as coral reefs. The US National Oceanic and Atmospheric Administration (NOAA) estimates that the annual value of US commercial and recreational fisheries dependent on coral reefs is US$100 million.

UNESCO calls on member states to improve regulation of their marine conservation areas to mitigate the negative effects of climate change. "The higher the level of regulation in a Marine Protected Area, the more effective it is in protecting local ecosystems," the report states. 

According to the organization, around 60% of countries have yet to include the restoration and conservation of marine forests in their Nationally Determined Contributions (NDC) plans, which are key to fulfilling the Paris Agreement. “We call on our Member States to invest in the restoration of marine forests and better regulate protected marine areas, which are important biodiversity reserves,” highlighted Audrey Azoulay, Director General, UNESCO in a press release. 

In Mexico, marine areas represent up to 65% of the national territory, while terrestrial areas cover only 35%. Moreover, of the 226 existing protected areas in the country, 31 have a terrestrial-marine surface, and only eight are exclusively marine. By 2024, 22.47% of the marine territory is under some category of protection, with only 5% highly or fully protected.