The Great Barrier Reef is destined to die
The Great Barrier Reef is dying; in fact, it is destined to die. Two-thirds of the Great Barrier reef is without the vital photosynthetic algae it needs to live and thrive.
Coral reef, Lizard Island National Park, Great Barrier Reef, Australia: Image Source: Conservation Planning
If you didn’t know, algae is vital to corals as they produce sugars that the corals need to metabolize and grow during the day. Marine algae are a type of phytoplankton (aquatic photosynthesizing microbes). At night, coral polyps eat a variety of plant and animal plankton. Phytoplankton are vital to the entire planet as they alone produce half of the Earth’s oxygen. If they die, we lose half of our supply of oxygen. Continued land clearing and deforestation also contribute. In fact, our oxygen levels have declined since the beginning of the industrial revolution and they continue to fall.
CO2 concentrations from Mauna Loa, Hawaii (black) and and Baring Head, New Zealand (blue). In bottom right corner is atmospheric oxygen (O2) measurements from Alert, Canada (pink) and Cape Grim, Australia (cyan) (IPCC AR4 2.3.1 adapted from Manning 2006).
What’s Happening?: Phytoplankton are sensitive to acid levels in aquatic environments. Carbon dioxide, as a result of fossil fuel burning, is increasing in our global environment. The oceans absorb much of this CO2. This makes the oceans more acidic (think carbonated water). This acidification creates problems for many species of phytoplankton as many can no longer build their bodies properly so they die.
Coral dying / bleaching out,
Corals are hit with a triple whammy:
1.) No algae, no food during the day.
2.) Less food during the day means less food for that coral ecosystem at night.
3.) Acid levels retard the growth of corals as well.
Our oceans are caught in a dangerous spiral that is becoming more and more improbable to correct with every passing minute.