Caption: Beach in Tenby, Wales

When you think of the ocean, different images might come to mind… playing at the beach… crashing waves… the many plants and animals that live in the sea!

The ocean gives us so many things. It provides life on Earth with clean air, a rich source of food and a home to thousands of diverse species. In fact, the Ocean Biodiversity Information System, state that there are 137,117 accepted species in the ocean (source). However, scientists also estimate that 91% of ocean species are yet to be classified (source).

The study of the ocean – known as Oceanography - brings together experts from a range of subject disciplines from Biology, Physics and Zoology through to Engineering and Geography. It has also been a point of fascination and curiosity to those working in the arts and humanities such as writers and artists. 

One of the first global ocean expeditions, called the Challenger Expedition, dates back to 1872- 1876 and was led by chief scientist, Wyville Thomson. H.M.S. Challenger travelled 68,890 nautical miles venturing into the North and South Atlantic and Pacific Ocean, and the polar seas. The crew took various measurements at 362 different sample/observation stations. This included: water depth, bottom water temperature, and the rate and direction of the current. They also took samples of the water and animal life (fauna) to study. Marine biologist, Sir John Murray (1895) described the Challenger’s findings as: "the greatest advance in the knowledge of our planet since the celebrated discoveries of the fifteenth and sixteenth centuries". Read more.

Since then researchers across the world have been leading many different studies to deepen our collective understanding of the ocean and the life it supports. For example, the Nekton Oxford Deep Ocean Research Institute have been working to find out more about how our ocean functions and how human activities impact it. In the short video below, Principle Scientist at Nekton, and Senior Research Fellow at University of Oxford Dr Lucy Woodall explains how the lead research on the deep sea and what these methods can tell us: 

https://www.youtube.com/watch?v=3c5tYfPD5gw

From the deepest ocean to lifesaving research 

One particularly ground-breaking discovery which continues to intrigue oceanographers and unlock secrets about the remarkable power and resilience of the natural world is that of hydrothermal vent systems. 

Hydrothermal vents are like hot springs on the ocean floor. They are mostly found in very deep waters on ocean ridges where tectonic plates (segments of the Earth’s crust) are moving apart from each other. Seawater moves deep into Earth’s crust and becomes super-heated, anoxic (without Oxygen) and acidic as it meets with the magma and very hot rock. Chemicals such as sulphur and methane leak into the water and when they come in contact with cold seawater the sulphides form large, solid chimneys.

Hydrothermal vents were first discovered in 1977 near the Galapagos Islands on the mid ocean ridge, initially sensed by a temperature spike and then from film photographs that were later processed (find out more). Scientists were shocked to see such high temperature readings in the darkest depths of the ocean! The vents were explored biologically for the first time in 1979 using specialist equipment and two ships. Since then approximately 300 have been discovered all across the world.

Due to the high temperatures, lack of sunlight, low or no oxygen and toxicity (sulphides and metals in the water), life on vents has adapted in many ways. The species differ according to the specific part of the vent they live on (on the chimney vs the sediment etc.) and whether a vent is active (discharging) or inactive (no current discharge). Notably, some of the life forms on vents have been shown to create their own energy independently of the sun. Instead, they convert the toxic vent materials into energy in a process called chemosynthesis. This process was not known about in 1977 when the vents were first discovered!

In the video below, researchers from the Natural History in London explain what hydrothermal vent systems can tell us in terms of how different species have evolved over time:

https://www.youtube.com/watch?v=fOGEuhQPKvY

Dr Woodall explains that: ‘The biological adaptation observed at vents has proved useful for humans. For example, enzymes like Pfu DNA polymerase, found in the microbes living at vent systems, have been the template to design enzymes that are now used in laboratories across the globe. They are used in a biochemical method known as polymerase chain reaction (PCR), to generate millions of copies of particular sections of DNA. This has applications in many scientific fields from conservation to medicine. More recently, PCR has been used in the test of COVID-19 to detect the Coronavirus from patients’ swab samples’.

Our ocean at risk

In addition to the unique wildlife they support, the vents are also rich in metals such as gold, copper, silver and zinc. This has attracted interest from deep-sea mining companies looking to use these materials for electronic items such as mobile phones and laptops and for galvanising products (adding a protective coating to prevent rusting).

Dr Woodall warns of the risks of this: ‘Deep-sea mining presents a major threat to vent systems as the removal of the sulphide deposits can destroy the habitat for many organisms making it difficult for them to continue living there. Other negative impacts include the disturbance caused by the introduction of artificial light (to shine the way through dark waters), noise pollution and sediment clouds in the sea water. This disturbance also affects areas much larger than the vents themselves’. To learn more about deep-sea mining. 

Because vents form in very deep ocean waters, most are found in the high seas and the activities around them are regulated by the International Seabed Authority (ISA) rather than by specific nations. ISA has approved exploration to seven mining contractors, all of which have to conduct environmental impact assessments of possible mining activities. Due to the multiple risks and unknowns, several groups including the European Union have called for a moratorium (freeze) on deep-sea mining until further research has been undertaken and we have a better understanding of the impact of such human activity (source). 

To read more about how people are treating the ocean read this article in our ‘Are humans ruining the Earth?’ Big Question. 

So, should we put our ocean first?

Dr Woodall says, ‘yes…by putting the ocean first we are helping our survival and that of the entire planet. We already know the ocean is vital to so many processes that regulate the planet and support life, however, just like with the discovery of vents, we continue to make new and important discoveries. Even if you never see the ocean, it is there in your daily life’. 

What do you think?

There are lots of things we can do to protect our environment. From recycling our newspapers and magazines to cutting down on plastic use. It’s small changes like these which can collectively help to make a big difference.

And when scientists point out these kinds of problems, it’s worth listening. That’s because once we know what the problems are, we can do things to stop them from getting bigger.

Professor Yadvinder Malhi, professor of ecosystem science at the University of Oxford, gives the example of something that happened in the late 1980s…Researchers warned the world of a ‘hole’ in the ozone layer. This was a particularly concerning discovery as the ozone layer is a thin part of the atmosphere which protects life on Earth from the sun’s harmful rays.

“It was to do with chemicals disrupting the ozone layer,” he explains, talking about CFCs (chloroflurocarbons) that were used in spray cans such as hairsprays, deodorants and more. “It was actually a success story. Everyone got together and made an agreement about [not using] those chemicals. The ozone layer is largely healing. It’s become a bit of a model.” To read more.

Problems in the ocean

Some of the issues we face today, though, are much more challenging. The ocean faces a lot of problems; many of these are linked, and all of them are created by humans.

Some of the ocean’s problems are created by climate change. This is a shift in the world’s average conditions (e.g. rainfall and temperature) largely put down to increased levels of carbon dioxide in the atmosphere through the burning of fossil fuels, agriculture, and land-use change (read more). Researchers have observed that the Earth’s surface is warming and weather patterns across the world are becoming much less predictable. Rising temperatures have resulted in Polar ice caps melting, sea levels rising and many places around the world being at greater risk of flooding in the future.

“This affects humanity”, says Prof Malhi, “as there are so many people living on the coast or coastal cities.”

“Another significant problem is the acidification of the ocean [sea water becoming more acidic] because of the extra carbon dioxide in the atmosphere. This has made it harder for coral to grow hard skeletons and other creatures such as oysters and sea snails to build and maintain their shells. It has a direct threat to aspects of life in the ocean.”

Prof Malhi thinks that although these are big problems, it wouldn’t be helpful just to think about saving the ocean. Instead, people need to think about how to change their impact on the environment more generally, which will help the ocean as well.

Below, academics from Oxford share their thoughts on the biggest environmental issues we face: 

https://youtu.be/0ZP7fWGZy-k

Where to start

Prof Malhi suggests that we need to think about two major things.

Firstly, we should think about how we generate power. The world’s primary source of energy is through the extraction of fossil fuels (coal, gas and oil), which creates lots of pollution and will eventually run out. Increasingly, we are trying to move towards ‘renewable’ energy, which relies on cleaner resources that don’t have an expiry date. These include wind, solar and water (hydro) power.

We also need to cut down on using cars and planes for our travel, and use public transport where we can. This reduces the use of fossil fuels in vehicles.

Secondly, we need to think about the food we eat.

“The dietary shift is an obvious one… to move away from heavy meat-based diets,” he says - although he doesn’t think that everyone needs to be vegetarian. Cutting down on eating meat means that fewer fields will be used for grazing animals. Keeping animals for food means lots of grain and water are needed to feed them, and eating meat also means a lot of energy is used to transport the food to shops.

Changing how we eat, travel and create energy might seem like massive tasks. And expensive too, if you’ve got to build more train lines, install more wind turbines and so on.

But Prof Malhi thinks it’s worth the investment.

“A lot of studies show now in some ways the transition pays for itself, partly because you avoid all the damage that climate change will do,” he says. “Plus, you create new technologies and new forms of employment.”

In fact, he thinks that the global coronavirus pandemic is an ideal time to start talking about making these changes as we all think about how we go about our daily lives.

“This might be an opportunity to do some ‘rewiring’,” he says. “This is an opportunity to create jobs and potentially regenerate the economy after the pandemic.”

Are there any lifestyle changes you could make to help protect the environment? 

What do you think governments should be doing to solve some of the problems that Prof Malhi points out?