Is the heart of the planet blue?…

by Bronte Hogarth 

When you imagine the heart of our planet, what is it you think about?

For Dr. Sylvia Earle, an ocean explorer who has spent over seven thousand hours underwater, the heart of our planet is the colour blue.

I was lucky enough to hear Dr. Sylvia Earle speak recently at the International Women’s Earth and Climate Summit, where she called for the need to explore and invest in the blue heart of our planet and the millions of little guys in the water.

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Dr. Slyvia Earle at the IWECI Summit

97% of our world is ocean, but the fact is that it has been neglected greatly.

Climate change, overfishing, acidification and other human pressures are changing the fundamental nature and systems of our oceans.

The recently published Fifth IPCC Assessment Report (AR5) expressed a great need to address the state of our oceans. Since pre-industrial times around 30 percent of human induced carbon dioxide emissions have been absorbed by the ocean.

This is a massive amount of carbon dioxide and it’s changing the chemistry of the ocean. It’s causing ocean acidification, which is dangerous for many marine organisms who maintain the life-cycles under the sea, and acidification can impact on water patterns as well. The AR5 is a landmark report on this topic as it’s the only international body currently reviewing ocean acidification science.

The earths surface temperature is also heating up due to more carbon dioxide in the atmosphere, and the blue heart of our planet is feeling it the most, absorbing about 80 percent of this additional heat.

What happens when water gets warmer? It expands, and this is leading to rising sea-levels.

Rising sea-levels are also being affected by the melting of glaciers, polar ice caps and massive ice sheets in Greenland and Antarctica due to warmer temperatures. All of this brings us to one obvious conclusion that our planet is changing and “we need take care of the oceans like our lives depend on it, because they do.” (Dr. Sylvia Earle)

The report estimates a global mean sea-level rise of between 26 and 82 centimetres by 2100. The worst case scenario is for a sea-level rise of 98cm. This will impact on many low-lying Islands which are at risk of disappearing completely into the ocean, and thousands of coastal cities too, like Venice, Italy, shown in the below picture taken during an intense flood of 2008.

Can you imagine a world like this?


Photograph by Andrea Pattero/AFP/Getty Images

Or what about a world where cult favourite fish Nemo didn’t exist?

Clownfish, are greatly threatened by oceanic acidification. It affects their sense of smell making it difficult to find sea anemone homes in which they live and depend on for protection from predators. Changes in the sea-scape could greatly affect these ‘little guys’ along with countless other marine life.


Clownfish in its anemone home.

The Fifth IPCC assessment will hopefully increase the discussion around the state of our oceans, especially about the direct effects of climate change. Nature is resilient, but as Dr. Sylvia Earle said, not if we don’t give it a chance.

Follow Bronte on Twitter @brontehogarth

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