5 teachings from the Pope on our struggling oceans

By Douglas Rader

In his stirring and beautiful encyclical, "Laudato Si," Pope Francis asks all of us to band together to protect and nourish our "common home." 

As part of these visionary statements, he provides a firm foundation for building a more fruitful future ocean, completely consistent with new science that we at Environmental Defense Fund have helped produce.

The science makes clear that human prosperity does not require the compromising of ecological systems, but rather that it benefits from restoring fish populations to levels that also can support greater extraction for food. 

Our work with partners around the globe to realize this dramatic triple-bottom-line "upside" can provide powerful support for the optimism implicit in Pope Francis' ground-breaking encyclical.

The fact that Pope Francis comes from a continent that sustains a huge number of Catholics, including many poor people who are dependent on fish for both food and livelihoods, as well as some of the world's biggest fisheries - with huge potential upsides - suggests that his opinion will matter a great deal.

Here are five specific teachings included in the encyclical that show his support for the world's struggling oceans:

1. Climate change threatens our oceans

"Carbon dioxide pollution increases the acidification of the oceans and compromises the marine food chain. If present trends continue, this century may well witness extraordinary climate change and an unprecedented destruction of ecosystems, with serious consequences for all of us. A rise in the sea level, for example, can create extremely serious situations, if we consider that a quarter of the world's population lives on the coast or nearby, and that the majority of our megacities are situated in coastal areas."

2. Marine biodiversity and fisheries in a fragile state

"Oceans not only contain the bulk of our planet's water supply, but also most of the immense variety of living creatures, many of them still unknown to us and threatened for various reasons. What is more, marine life in rivers, lakes, seas and oceans, which feeds a great part of the world's population, is affected by uncontrolled fishing, leading to a drastic depletion of certain species."

Overfishing: How bad is it?

"Selective forms of fishing which discard much of what they collect continue unabated. Particularly threatened are marine organisms which we tend to overlook, like some forms of plankton; they represent a significant element in the ocean food chain, and species used for our food ultimately depend on them."

3. Coral reefs need our help

"In tropical and subtropical seas, we find coral reefs comparable to the great forests on dry land, for they shelter approximately a million species, including fish, crabs, molluscs, sponges and algae. Many of the world's coral reefs are already barren or in a state of constant decline... This phenomenon is due largely to pollution which reaches the sea as the result of deforestation, agricultural monocultures, industrial waste and destructive fishing methods, especially those using cyanide and dynamite.

It is aggravated by the rise in temperature of the oceans. All of this helps us to see that every intervention in nature can have consequences which are not immediately evident, and that certain ways of exploiting resources prove costly in terms of degradation which ultimately reaches the ocean bed itself."

4.  The importance of marine sanctuaries

"Some countries have made significant progress in establishing sanctuaries on land and in the oceans where any human intervention is prohibited which might modify their features or alter their original structures. In the protection of biodiversity, specialists insist on the need for particular attention to be shown to areas richer both in the number of species and in endemic, rare or less protected species.

Certain places need greater protection because of their immense importance for the global ecosystem, or because they represent important water reserves and thus safeguard other forms of life."

5. Needed: Oceans governance

"Let us also mention the system of governance of the oceans. International and regional conventions do exist, but fragmentation and the lack of strict mechanisms of regulation, control and penalization end up undermining these efforts. The growing problem of marine waste and the protection of the open seas represent particular challenges. What is needed, in effect, is an agreement on systems of governance for the whole range of so-called 'global commons."