Protecting the seas and oceans: how can it be done?

On the picure you see the sunset about the sea — **View of the wide open sea**
Source: FG II 2.3 / UBA

The German Environment Agency is committed to protecting the oceans, which are more important than ever. They buffer climate change, host biodiversity, provide food and raw materials, serve as living and recreational spaces, and are transport routes. At the same time, the North and Baltic Seas face many human activities, leaving their marine environment in poor condition.

The seas and oceans are crucial for all life on Earth. They produce half of the world's oxygen, are home to around 80 per cent of all animal species and cover almost three quarters of the Earth's surface. The oceans play a key role in the climate system, as they absorb around a third of the carbon dioxide (CO₂) produced by humans from the atmosphere through natural gas exchange. At the same time, they are important components of the global water cycle and distribute heat via their currents.

From a distance, the seas appear endless and untouched. But on a closer view, it becomes clear that plants and animals and their habitats, especially near the coast, are significantly affected by human use. Many pollutants and too many nutrients from municipalities, industry and agriculture end up in the seas via rivers, direct discharges and the air and have harmful impacts on the marine ecosystem.

But human activities on the high seas, such as global shipping, industrial aquaculture, deep-sea mining and the expansion of offshore energy production, also have a negative impact on the marine environment. Waste, especially plastic waste including microplastics, is omnipresent. Underwater noise disturbs and harms whales, dolphins and fish in particular. In the past, our local seas were also used as a dumping site for old munitions, the toxic explosives and chemical warfare agents of which are now detectable in seawater, sediment and living organisms. Additionally, the ongoing climate change and the associated increase in warming and ocean acidification have additional global impacts on marine ecosystems, as well as technological interventions through marine geoengineering with uncertain consequences for the marine environment.

Changes have been regularly documented for decades, which has led to comprehensive knowledge about human activities and their impact on the seas and oceans. Based on the data collected, the biological, chemical and physical state of the marine environment is assessed at local, national, regional and global levels. It has been shown that a poor environmental status of the seas and coasts also has a negative impact on their productivity and other functions that are important for humanity. Intact marine and coastal ecosystems can play an important role in both climate protection and climate adaptation and make important contributions to human well-being, including in terms of food supply, transport and recreation. This also applies to the polar regions, which play a special role in the climate system and are an important ‘engine’ for global ocean currents.

The German Environment Agency (UBA) has been working for decades to determine the state of the seas and to reduce marine pollution and is also the competent authority for permitting and monitoring scientific marine geoengineering projects. Concepts and measures for the protection of the seas within the framework of the regional marine protection conventions for the Baltic Sea (HELCOM) and the North-East Atlantic including the North Sea (⁠OSPAR⁠) are particularly relevant. At European level, the Marine Strategy Framework Directive (MSFD) also aims to achieve good environmental status. To this end, the federal states and the coastal federal states are working together to tackle the various challenges and regulations (‘marine governance’) in order to improve the protection of the seas and oceans and make their utilisation more sustainable.

A particular challenge in the future will be to harmonise the constantly growing ‘blue economy’ with the protection of the seas and oceans in order to maintain or restore the balance between use and protection under the influence of advancing climate change. Sustainability, the precautionary principle and a holistic, ecosystem-based approach must be the basis of our actions, and the various uses must be assessed and regulated cumulatively, i.e. holistically. Protecting the marine environment is vital, not least for humanity, and worth every effort.