review by Ciprian Diaconita
Covering 71% of our planet’s surface and containing 97% of it’s water, our oceans play a major role in our climate and weather control. They are also home to more than a quarter of all recorded species and represent the biggest and most effective carbon sinks on Earth. Yet our oceans, and their vital role, have been largely ignored and their resources abused around the world, to the point of collapse. With Rio+20 ending without any concrete plan of action, we analyse the importance of oceans to our planet’s future and how world leaders have put a blind eye to its degradation and protection.
At the Alternative Rio+20 Conference organised by Campaign against Climate Change, which took part last week, Peter Challoner from the National Oceanography Centre, Southampton and Elisabeth Whitebread from the Global Ocean Legacy as well as The Green Party, discussed the importance of oceans and the threats they face.
So why are our oceans this important? Quite simple, without oceans, life as we know it, wouldn’t exist.
Oceans have constantly influenced our climate and weather, acting as a thermostat to our planet, storing the sun’s energy in the form of heat, then circulating it through global currents, shaping our weather systems and the ecology of our planet. Oceans are also important in sequestrating carbon dioxide, as well as a great source of oxygen. They release more than half the oxygen that humans and other animals need to survive; meanwhile about 55% of all biological carbon is sequestrated by marine organisms, mangrove forests, salt-marshes and sea-grass meadows. With a biomass of only 0.05% that of land forests, oceans prove a very effective carbon sink.
When taking into consideration that more than 40% of the world population are living near coastal areas, oceans also provide food security through fisheries and shipping routes (about 90% of world trade uses oceans as a mean of transport).
In short, oceans keep our climate in balance, provide us with almost half the oxygen, sink at least as much carbon, are a vital source of food and help us transport goods around the world in huge quantities, while incorporating a vast biodiversity that is yet to have been fully discovered. Keeping this in mind one would think that oceans should top all agendas related to climate change and environmental degradation. But it doesn’t. Our oceans are hanging by a very thin thread and time is running out.
Threats to our oceans include:
Melting of Arctic ice
Naturally Arctic ice melts and refreezes on an annual basis. But with increased greenhouse gases in the atmosphere temperatures in the Arctic have risen twice as fast as the global average resulting in significant reductions in sea ice. This leads to a diminished albedo effect, with more radiation being absorbed by the oceans, therefore increasing global warming and sea level rise, while also carrying unknown consequences to ocean currents and weather events.
With more and more CO2 released in the atmosphere the oceans’ absorption capability is stretched to the limits. This increase causes a decline in PH and calcium carbonate saturation levels, affecting a variety of species such as phytoplankton and ecosystems, such as coral reefs. Phytoplankton represent one of the most important building blocks for ocean life, responsible for photosynthesis and a main source of nutrition to huge variety of species.
Plastics are just some of the hundreds of pollutants we put in our aquatic environments. In many countries, rivers, streams and coastal areas are used as a dump site for wide range of household and industrial pollutants. Nest described as a collecting system, it gathers waste which eventually ends up in our oceans, making them a marine dump site. The resulting plastic pollution is causing a high mortality within the marine fauna affecting mammal, bird and reptile species.
Such is the scale that an “island” of floating trash, mostly plastics, formed in the Pacific Ocean. Called the Great Pacific Garbage Patch, it stretches over hundreds of km between California and Hawaii. As plastic can take hundreds of years to bio-degrade, it survives for a long time in the oceans. One of the few processes breaking it down is photo-degradation by sunlight which makes matters even worse. The plastic is broken into smaller and smaller pieces, entering the very basis of the food chain and so affecting everything from small organisms to birds and large mammals.
With more than 70% of our world’s fish stocks over exploited or depleted, overfishing represents one of the greatest threats to marine ecosystems and biodiversity.
Our oceans are overfished; there is a huge fishing industry that operates mostly unregulated and uncontrolled, resulting in our oceans being fished at an industrial scale. And as the industry is seeking large fish species, such as tuna or cod, the affected species are fished to extinction levels. To make matters worse the by-catch policy in place means that fish captured outside the quota gets thrown back, making the industry extremely wasteful.
Loss of habitat
Known as blue carbon sinks, mangrove forests, sea-grass meadows and salt marshes, play a key role in sinking carbon from the atmosphere, as well as their capacity to restore fish stocks, protect the shoreline from extreme weather events and sea level rise. However according to UNEP these coastal ecosystems are disappearing at an alarming rate, losing half of their sink capacity since the 1940s, mainly due to deforestation, uncontrolled coastal development, pollution by plastics and chemicals, overfishing, exploitation and loss of biodiversity.
So what can be done to protect our oceans?
One important step must be the establishment of large marine reserves protecting oceans from overfishing, mining and waste disposal. A first step has been taken by Australia which recently created the largest network of marine reserves in the world. Although debated in terms of efficiency and implementation, this example should be followed, especially by the United Kingdom. Adding all 14 UK Overseas Territories, and their surrounding water areas, UK ranks fifth in the world in terms of ocean territory, a huge potential for creating marine reserves. Unfortunately this aspect has been bypassed by legislation. Reserves have already been created around Chagos, South Georgia and the South Sandwich Islands, Bermuda and Pitcairn but much more can be done. At the moment marine protected areas cover less than 2% of the entire ocean surface, with fully protected areas at less than 1% (http://www.marinereservescoalition.org/conservation/uk-overseas-territories/). These figures paint a picture of a global disregard towards the safekeeping of our oceans.
By protecting and restoring coastal ecosystems we are rebuilding their carbon sink capacity while also increasing biodiversity and the capacity to adapt to climatic changes, one example is how salt marshes can prove a much better solution in adapting to sea level rise as opposed to hard defences.
So how did the protection of our oceans fair in the Rio+20 agenda? As it happens the importance and potential of our oceans has been marginalised. Greenpeace described this failure to take action as a final straw towards a “war footing”. Present almost since Earth’s formation (studies put the existence of oceans as back as the hellish Hadean era), and possibly linked to the formation of life itself, as recent studies into zircon show, it is amazing and utterly dismaying how we can destroy its basic role in just under 100 years.
Green Party Marine and Costal Policy
Mother Nature Network: What is the Great Pacific Ocean Garbage Patch?
The Guardian: Furious Greenpeace moves to ‘war footing’ at Rio+20
Marine Reserves Coalition: UK Overseas Territories
Alternative Conference for the Rio Summit