We know more about the surface of the moon than we do about the ocean...
Written by Dr George McGavin
In a special feature for our upcoming event on the 3rd May, zoologist and broadcaster, Dr George McGavin, tells Love It Local magazine why we all need to look after our blue world!
It is impossible to overstate the importance of the ocean. It has been home to life on our planet for around four billion years.
Ocean covers 70% of the world’s surface and it is essential for the regulation of global temperature, the function of the water cycle, the levels of oxygen and carbon dioxide. It also makes up 90% of the biosphere – the sum total of all the parts of Earth where life exists. Without the ocean there would have been no life on Earth at all. The first life-form able to turn sunlight into energy was born here as was the first multicellular life, as well as the first organism with a brain. We, and all other animals, really are creatures from the blue lagoon.
The Mysteries of the Deep Ocean
It may seem that there is a lot ocean to explore but actually there’s not as much of it as we might imagine. In fact, compared to the thickness of the Earth’s crust, the ocean is more like a thin membrane around the planet.
Nevertheless, only around five percent of ocean has been explored and we have only described a relatively small fraction of all the species that might live there. It’s fair to say that we know more about the surface of the moon than we do about the ocean and very few people have ventured down into the deep and dark abyssal regions.
UK: A Coastal Kingdom
The UK’s coastline is over 22,000 miles long but you’re never that far from the seaside. The Ordnance Survey identifies the Derbyshire village of Coton in the Elms as the furthest place in the United Kingdom from coastal waters. Even so, it would only take you a couple of hours to drive, or a couple of days of brisk walking to cover the 70 miles or so to go paddling at the seaside. But most of
the population live a lot closer to the sea than this and a visit to the seaside is a very popular day out. I grew up in Edinburgh and the family summer holiday was often spent somewhere on the West coast of Scotland where I would study the life in rock pools using home made surveying equipment, or collect skulls and bones I found along the strand line. I never imagined that before my life ended I would think twice about swimming in the seas off our coast and much less witness a catastrophic decline in global biodiversity.
Threats facing the Ocean
There was a time when there were relatively few humans on Earth and what we did to the natural world was of little consequence. That is certainly not the case now.
Our success has come at an enormous cost to the natural world. Today the demands we have made of the ocean have far exceeded its capacity to meet them and our institutions have failed to protect it. Vast quantities of untreated wastewater and sewage, laced with the myriad drugs we take on a daily basis and agricultural fertilisers and pesticides that have run off the land, flow steadily into the ocean. Novel chemicals such as polychlorinated biphenyls – highly toxic and carcinogenic compounds used in industrial processes
and consumer electronics, whose production was eventually banned in 2001, have contaminated the environment. These and other chemicals, known as persistent organic pollutants, do not just disappear. They last for a very long time and will continue to wreak havoc in marine ecosystems for many years to come.
The devastating impact of Overfishing
We take far too much from the ocean. One third of commercially fished waters are now classified as ‘overfished’ which simply means that the fish stock is being used faster than it can be replaced. Some parts of the ocean are now considered dead zones. The ocean is warming and becoming acidified due
to the high levels of carbon dioxide we have released into the atmosphere by burning fossil fuels.
Plastic – the wonder material that came at a price
At school I learned that plastic was the wonder material of the future that would revolutionise our lives. What was left out of this rosy picture was that most plastics would stay around for a very long time after their useful life had ended. In the early 1950s just two million tonnes were
produced. Today over 450 million tonnes a year are produced
– that’s more than the weight of all the humans on Earth. Not nearly enough plastic is recycled and at least two million tonnes of it ends up in the ocean where it will slowly break up into ever smaller particles. These micro-plastics can now be found in every part of the biosphere as well as in our blood, bones and
On Christmas Eve 1968, when I was a fourteen years old (photo below), Apollo 8 astronaut William Anders took a colour photograph of Earth from the surface of the moon. Earthrise, as the image became known, showed that we live on a small and rather beautiful blue planet.
It’s high time we started looking after it.
A chance to see George McGavin on 3rd May in Wareham!
You can see George McGavin talk about his passion for the marine world in our special evening ‘Our Blue World’ on the 3rd May at Lady St Mary’s in Wareham.
George will be joined by Cellists Hugo and Jesper Svedberg, who will be performing a programme of music too.
Profits from the evening will go towards the Wild Seas Centre at Kimmeridge (Dorset Wildlife Trust).
Read more details and book tickets to for the George McGavin evening.
