The ocean plays a major role in regulating the Earth’s climate. It produces half the oxygen we breathe and absorbs vast amounts of carbon dioxide and excess heat from the atmosphere. And just as climate change climate is effecting our land, climate change is effecting our oceans.
Oceans are becoming warmer, sea levels are rising and the increase in carbon dioxide has started a process of acidification in our ocean.
The blue truth is, the process the ocean uses to protect us (absorbing carbon dioxide and heat) is destroying it.
For decades, the ocean has been acting as a buffer, soaking in the carbon dioxide dumped into the atmosphere by burning fossil fuels. It has absorbed most of the extra heat produced by elevated atmospheric carbon dioxide levels.
Ocean heat not only determines sea surface temperature, but also affects sea level and currents. It affects flooding, which becomes more frequent as sea levels rise. Changes in sea temperature affect habitats and the behaviour of marine life as they are forced to adapt or die.
Safe levels of CO2 in the atmosphere is considered to be 350 parts per million (ppm) but in September 2016 we reached 400 ppm
Blue carbon is carbon captured by oceans and coastal ecosystems. Ocean plants take in carbon dioxide and give off oxygen, just like land plants, but they are even more effective. Ocean vegetation can absorb four times more carbon than forests. Blue carbon sinks - mangroves, saltmarshes, seagrasses and estuaries - capture 1 billion metric tons of carbon every year.
If not for the ocean, we’d be choking on our own CO2. Yet we are destroying its ability to help us combat these ever increasing CO2 levels by degrading wetland ecosystems, prioritising instead urban expansion and coastal development. This will accelerate climate change.
Unsustainable infrastructure (such as port expansion) in marine sensitive areas creates the double whammy- increasing CO2 levels by pumping fossil fuels into the air and destroying the ecosystems which could absorb it. Big business is giving us the disease and denying us the cure.
Coral reefs are one of the most diverse ecosystems on the planet and one of the most useful. They shelter coastlines from waves and storms, they provide homes for one quarter of the world’s sealife and are breeding grounds and nurseries for many more. The reef provides nitrogen and nutrients for the food chain and assists in carbon and nitrogen fixing.
To date, we have lost 27% of the world’s coral reefs. If present rates of degradation continue, it may be too warm for coral reefs to exist.