Ocean acidification could reach levels not seen for millions of years

In the pages of the journal „Earth and Planetary Science Letters”, syndromeoł scientistow from Cardiff University reconstructed ocean acidity levelsoin and atmospheric CO2 over the past 22 millionoin years. Researchers have noted that we may be approaching levels thatory has not been visible for a millionoin years.

Ocean acidificationow occurs when carbon dioxide from the atmosphere is absorbed by seawater, making the water more acidic – it has a lower pH. About one-third of the CO2 released by burning coal, oil and gas dissolves in the oceans. Since the beginning of the industrial era, the oceans have absorbed about 525 billionow tons of CO2, equivalent to about 22 million tons per day.

Scientists based their study on analysis of fossils of tiny sea creatures thatore once lived near the surface of the ocean. The chemical composition of the shells gave researchers an indication of theowks regarding the acidity of water, in whichothe creatures lived.

Based on this information, scientists were able to put new data on the level of theoin pH and CO2 in the context of a series of roof carbon dioxide emission scenarios recognized by the International Team ofoł ds. The report of the Intergovernmental Panel on Climate Change (IPCC). If current levels of carbon dioxide emissions continue, CO2 levels in the atmosphere will reach nearly 930 parts per million (ppm) in 2100, cfownaniu to about 400 ppm currently.

In the same scenario of maintaining CO2 emissions, the pH of the oceanoin 2100 will drop to less than 7.8, in porownaniu to about 8.1 today. This is very important because the pH scale is logarithmic, meaning that a decrease of just 0.1 pH units represents an increase of 25 percent. acidity.

British scientists have found that similar levels of atmospheric carbon dioxide concentration and ocean acidityoin the last time Earth was seen in the middle Miocene – which is about 14 millionoyears ago, when global temperatures were about 3 degrees Celsius. Celsius higher than at present. Scientists stress, however, that in theotime it was the result of the natural geological cycle of our planet. Currently influenced by human activities.

– The new geological documentation of ocean acidification that we have developedow shows us that on our current emission trajectory, ocean conditions will be different than marine ecosystems have experienced for the past 14 millionoin years – said study leader Sindia Sosdian of Cardiff University.

– The current pH is already probably the lowest in the last 2 millionoin years. A thorough understanding of what this means for the ecosystemoin the sea, requires long-term laboratory and field studies, as well as additional observations from the recordoin fossil – explained wspoauthor of the study Carrie Lear. It should be noted that a decrease in pH means an increase in acidity.

Although Lear mowi o additional research, we are already able to say that an increase in acidity is nothing good for the marine ecosystemow. Rapid flow of carbon dioxide into the oceanow seriously threatens marine life.

Shells someorich animals, those most sensitive to pH changes, may simply dissolve in more acidic water. We are talking about clams, corals, abortedoThe marine snails or someorych types of plankton, whichore are food for other, larger creatures. This means that with an increase in acidity will be plantedocony food chain.

Acidification of the oceanoin means roAlso a greater energy expenditure for the bodyoin marine, whichore will have to maintain the proper chemical composition of their comorek. This may result in a lack of energy for other biological processes, such as growth or reproduction.