Acid Oceans Could Drastically Cut Down One of The World's Biggest Oxygen Producers

As our oceans acidify, the tiny floating organisms that supply our world with as much as a fifth of its oxygen will be in dire straights.

The creatures, called diatoms, will be deprived of the building blocks they need to build their protective shells, which come in all sorts of dazzling shapes.

Researchers found that this could reduce their numbers by up to 26 percent by the end of the century.

Diatoms are one of the most important plankton groups in the ocean.

Their decline could lead to a significant shift in the marine food web or even a change for the ocean as a carbon sink.

40 percent of the ocean's photosynthesis is made up of single-celledalgae, which is one of the main components of the biological pump that takes CO 2 out of our atmosphere.

They are one of the reasons the oceans have been able to absorb the excess CO 2.

The CC BY-SA 4.0 is written by Samarpita Basu.

The biological carbon pump has a role in it.

Our excess CO 2 reacts to form more hydrogen ion, increasing the water's acidity. Since industrialization, carbonate concentrations have decreased by 10 percent.

Calcium carbonate is a vital molecule for most marine animals because it is part of their shells.

If the concentration of carbonate drops too low, calcium carbonate can be dissolved. Some animals are dissolving their shells.

It was thought that diatoms, who build their intricate glass houses out of completely different materials, would not be affected by ocean acidification, and possibly even benefit from the increases in CO 2.

The frustules are the outer shells of the phytoplankton, which are made out of the silica that floats in the ocean.

The new research shows that a factor was missed in previous studies. As the water's pH drops, the vital building blocks will start dissolving more slowly, meaning more of them will sink into the ocean before it becomes light enough to stay afloat.

This leads to more silica on the ocean floor, far out of reach of the diatoms floating in the light they use to turn CO 2 into oxygen, water and carbohydrates, making it hard for them to build their frustule homes.

The frustule is under 1,500x magnification. Massimo brizzi is a member of the CC BY-SA 4.0.

The researchers discovered this by adding different concentrations of CO 2 to simulations of future warming scenarios.

They evaluated the samples from different depths. Modelling and previous studies show that the amount of floating silica could decline by up to a quarter by 2200.

The other life on our planet will be affected by a huge loss of these organisms.

The team states in their paper that it is more difficult to assess the consequences of carbon cycling and the functioning of the food web.

The findings show how unexpected feedback mechanisms in Earth's systems can drastically alter environmental and biological changes that we may think we understand.

The complexity of the Earth system and the difficulty in predicting the consequences of man-made climate change are highlighted in the study.

If we don't counteract climate change swiftly and decisively, we will be running incalculable risks.

The research was published in Nature.