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Francesca Koe’s Blog

Scorecard for the Sea: The Ocean Health Index

Francesca Koe

Posted September 4, 2012

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Wincing from the cold of the ocean spray on his face, a fisherman hauls ice-covered crab pots from the frozen waters of the Bering Sea. Half a world away, beneath warm waves a tour guide leads her group through a maze of colorful Bahamian corals, past schools of angel fish, and the occasional giant sea turtle.

These scenarios might be as different as night and day, but both the fisherman of the frigid north and the tour guide of the tropics depend on the ocean to survive.

To feed, employ, and sustain the world, our oceans must first be in good health. It is becoming increasingly clear that humans have a substantial impact on these marine ecosystems, and that these impacts are not just threatening the high-seas, but also the humans that depend on them for their livelihoods and well-being.

The health of our oceans is, therefore, primarily a human concern. But how do we measure the health of something as vast and bewildering as an entire ocean?

 For many years, scientists have struggled to find a way to make the concept of ocean health meaningful and measureable. There have been a few breakthroughs but no real solution to allow us to concretely measure if things are good or bad, getting better or worse, and by how much? That is, until now.

Published in last week’s issue of the journal Nature The Ocean Health Index is a groundbreaking tool that allows us to take a look at how we as humans benefit from the big blue. The Index examines social, economic, and ecological factors, scaling both globally and locally to give us an accurate assessment. It finally gives us the baseline we need to measure progress.

To make things simple the Index offers categories -- benefits like “food provision”, “sense of place” and “carbon storage” are given scores from zero to 100 based on a region’s ability to provide these benefits sustainably, now and in the future. The weighted sum of these individual numbers yields an ocean health score for a given region, or when combined, the globe.

This approach makes it easy to calculate the many different ways we use, benefit from and value the ocean. It also offers a method to combine what would otherwise be apples and oranges. It is comprehensive and flexible in examining ocean health across all corners of the globe, and tracks progress over time. 

Global Index.JPG

Until we developed this tool, a lot of people talked about the importance of healthy oceans, but we had no way to measure overall ocean health in a given place,” said Dr. Karen McLeod, Director of Science at COMPASS. McLeod, who has been working on this project since its inception, believes that the tool encourages the public to ask questions about their country’s ocean health – to celebrate successes, learn from failures, and appreciate the full spectrum of benefits that the oceans provide. “The Index transforms the powerful metaphor of health into something concrete and quantitative. This understanding of the whole, not just the parts, is necessary to conserve and restore our oceans ecosystems. We can’t manage for overall health if we don’t measure it.”

Individual country and global scores were released online last week. Country scores range widely, with the highest score of 86 recorded for the nearly pristine Jarvis Island, which boasts incredible coral reef ecosystems. Globally, the oceans received a score of 60 out of 100, evidence that much work remains to be done to create a more sustainable relationship between humanity and our oceans.

Please share this article with friends to encourage a conversation about the many ways that we depend on a healthy ocean. After all, even though the individual relationships we have with the ocean may vary dramatically, we all do share a common connection to the sea -- from the food we eat to the beaches we love to the air we breathe, there is a little bit of ocean in us all.

More details on the Ocean Health Index and the scores and how they are calculated can be found on the Ocean Health Index website.  

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