Mankind and the oceans

Mankind’s interaction with the oceans is a real paradox. Although the oceans are our greatest resource, small consideration is given to its protection and conservation.

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Mankind's fascination for the oceans is still intact

Oceans represent 70% of the planet surface, 97% of the water resources and they contain 80% of the living creatures on the planet. Oceans also play an important role in releasing oxygen in the atmosphere and are the principal carbon pump. They are of primary importance for all human activities and for life itself: they provide us with oxygen, water, food and mitigate continental temperatures. Oceans are crucial for our economy, a great amount of fossil fuel is stored in their depths and they are fundamental commercial route for the exchange of goods by maritime transport.

Ironically, oceans’ resources are today in danger due to the intensification of human activities. Our impacts on the oceans can be classified into three categories:

  • The burning of fossil fuels has the effect of: increasing the temperature of the oceans, their acidification (related to the absorption of atmospheric carbon dioxide) and the rise of the sea level.
  • Unsustainable fishery such as overfishing (exceeding the level of fish population renewal), fishing bycatches and destructive fishery techniques (bottom trawling fishery, blast fishing) are responsible for the depletion of the oceans’ life resources.
  • The consequences of all kind of ocean pollution such as physical pollution (radioactivity, acoustic pollution), biological pollution (invasive species) and chemical pollution (micro pollutants, plastic pollution, oil spills). The main issue dealed by our organization, marine debris, is related to this last category.
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Human activities strongly affect marine ecosystems

We see the oceans as being an infinite environment that can withstand everything. But today, the devastating consequences of human activities on ocean’s integrity has been proven. For example, fishery resources decreased of 50% since the industrial revolution.

To illustrate the current state of the oceans, here is a model developed by the scientist Benjamin Halpern. The picture below represent the impacts of human activities on marine ecosystem on a global scale.

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Global map of impacts of human activities on marine ecosystems based on 19 anthropogenic stressors. Weak impact < 2.7, strong impact > 4.1. Source: Halpern et al. 2015, Nature Communication.

Halpern shows that a large part of the oceans (41%) is strongly impacted by human activities and that nowhere pristine conditions are preserved. The conjunction of our strong dependence on marine resources and the threats that the oceans have to face represent major environmental risk often underestimated by the general public. All human activities driving this risk are related to overconsumption. This is valid for energy consumption (fossil or nuclear) and all product consumption.

The issue of accumulation of plastic waste is a great illustration of the harmful consequences of overconsumption since the plastic is a wasted product, producing non managed waste with multiple impacts on the environment.