Is the sea polluted

What threatens our seas

Our seas are in danger. Pollution, overfishing, warming and acidification are just some of the issues that affect the ocean as a habitat. The consequences not only endanger life in the water, but also change the climate on land. We have dealt with the essential threats.

Around 18,000 plastic parts float in the sea per square kilometer.

Deliberate seawater pollution

Huge rubbish carpets whirl through the oceans in the carousel of ocean currents. Birds stick together to form black lumps of oil. Marine animals nibble their way to death on colorful toys and line up as a poisonous link in the food chain.

Pesticides, herbicides, artificial fertilizers, detergents, sewage, oil and vast amounts of plastic particles and other solids turn our oceans into hazardous waste dumps. An estimated 675 tons of garbage end up in the ocean every hour, half of which is plastic.

There are now up to 18,000 plastic parts per square kilometer of sea. A carpet of rubbish the size of Texas, the "Great Pacific Garbage Patch", is floating in the North Pacific vortex between North America and Asia. It wasn't until 2010 that another giant garbage island was discovered in the Atlantic Ocean. They are memorials of centuries of ignorance.

In many cases, garbage and sewage end up in the sea via detours. Nitrogen-rich fertilizer from agriculture, for example, seeps into the groundwater or rivers and thus flows towards the sea. There it stimulates the algae growth and these in turn remove all oxygen from the water. What remains are so-called death zones: 400 of these oxygen-poor or even oxygen-free and therefore lifeless areas are already known.

In addition to the physical, there is the “acoustic pollution” of the oceans: the humming of ships, drilling for oil and the sound of sonar devices impair communication, orientation and reproduction of large marine mammals. Whales, researchers observe, try to counter the noise level with louder shouts. But the sound pressure of sonar technology can damage the brain and circulation of marine mammals so badly that they lose their orientation and get stranded.