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Ocean acidification is a major threat to coastal marine life

Scientists believed marine ecosystems could adapt to warming waters. However, ocean acidification of seas is posing another threat to this process.

Here at Thred, we’ve showcased several projects which have been designed to deal with one of the ocean’s biggest man-made problems – plastic pollution.

Lately though, scientists have been seriously concerned about one of the ocean’s natural processes, particularly its ability to absorb carbon dioxide, or greenhouse gases.

The vast blue regions of our planet naturally absorb at least one-quarter of all carbon emissions that come from burning fossil fuels.

In the early days, researchers viewed this as a positive finding. Surely it means less carbon in the atmosphere, which could ultimately help slow the warming of our planet?

Unfortunately, they were wrong. We now know that continuously emitting such large quantities of carbon is causing the ocean to become not just warmer, but more acidic.

For a short time, our oceans were coping. Rivers would carry minerals and chemicals from rocks nearby and eventually empty them into the sea, where they’d keep the water’s pH levels stable.

But as we inch nearer to global temperature limits, and carbon emissions aren’t decelerating, the ocean is struggling to stay balanced. The window for recovery has narrowed completely.

Researchers remained initially optimistic about the reality of warmer oceans.

They believed that as a result of warming waters, animals which lived in temperate areas might die. However, the possibility that tropical species would migrate to populate empty coastal regions seemed like a decent solution.

But nature is unpredictable, and this forecast wasn’t correct. In fact, what scientists have found is that warmer waters combined with acidification is causing whole ecosystems to collapse.

In the past 200 years, acidity levels have increased by 30 percent. This altering of environmental chemistry has happened faster than any other biological change in over 50 million years.

Some of the hardest hit areas are coastal regions. They are quite literally being ‘burned’ by warmer sea temperatures, in a process called ‘tropicalisation’.

Habitats such as seaweeds and anemones can’t adapt fast enough, so when they die, the fish which rely on them for safety and breeding also begin disappearing.

Shells of molluscs such as oysters, mussels, snails, and crabs are unable to form, as the acids eat away at them in their softer, developing stages.

Home to lobsters, fish, and dolphins are delicate kelp forests. Dotted around the world, many are turning to slimy graveyards at the ocean floor, harmed by warm waters and acidic environments.

Scientists hope for a positive wave of ‘tropicalisation’ – where coral reefs would replace cool water kelp forests – is dwindling.

The growth of reef-forming corals depends on stable water pH levels. If this environment isn’t available, we risk losing marine life in all areas.

It’s not all doom and gloom though. In-depth awareness of the direct causes and effects should be enough to motivate prevention.

We can no longer deny that CO2 emissions are responsible for the destruction of basically every natural ecosystem on our planet, even in the undersea areas that most don’t give much thought to in day to day.

The only way to save these environments is to reach net zero carbon goals, which would stabilise ocean temperatures and provide time for levels of acidification to balance out.

With Cop26 and The UN Ocean Conference coming up, the pressure is on. Carbon companies and major world leaders, we’re looking at you! It’s time to make some changes.


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