Climate change and sea ph – The vents of Ischia studied by Shawna Foo


I dedicate this post to my two friends Shawna Foo and Danny Ormay with whom we shared amazing moments, wonderful talks about drawing a world of people living in harmony and respect with Nature, with whom we cleaned the sea bed from garbage and that unfortunately left Ischia after six wonderful months together. Alessandro Mattera

Climate change is affecting our oceans. One of the most important changes that we are seeing is the decrease in ocean pH. Currently, the oceans are at a pH of 8.1, but as the ocean absorbs excess CO2 gas from the atmosphere, we can expect the oceans to decrease to a pH of 7.6 by the end of the century.

For the many microscopic animals that live in the ocean, this could be harmful for their development.  

Here follows the research of Doctor Shawna Foo conducted at the Anton Dohrn Station of Ischia thanks to the Supervision of Doctor Maria Cristinaantono-dohrn Gambi.

Shawna Foo

“I have come from Australia to work in Ischia, as it is a very unique site. Around the Castello Aragonese, due to volcanic activity, there are carbon dioxide (CO2) gas seeps where the CO2 gas bubbles from the seabed creating a ‘champagne sea’.”

The CO2 dissolves into the surrounding water, lowering the pH to levels that we can expect to see with continuing climate change. This means that we have a glimpse into the future, as we can see the long term effects of low pH on the marine biodiversity.

Adult sea urchin, Paracentrotus lividus (photo: Shawna Foo)



My work focuses on sea urchins.

Sea urchins develop through a fragile ‘larval’ stage (Photo 2). To understand how sea urchins will be affected in the future, we grew sea urchin larvae in the CO2 gas sites at the Castello Aragonese. As the larvae are microscopic, we had to use special containers with a fine mesh, which allowed water to flow through, but also retained the larvae to look at under the microscope.

By looking at the development of the larvae at these sites, we can understand how their development will be affected by low pH, and whether they are still able to grow a skeleton.

Climate change is affecting the oceans, and a decrease in pH is only one of the problems. You can see for yourself.

48 hour old sea urchin larvae. The length of the arms are only 200 micrometres!! (photo: Shawna Foo).
The experiment underwater at the Castello Aragonese. The larvae are contained in the white ‘homes.’ You can also see the CO2 bubbles which lower the pH of the water. In the bottom right is the pH meter which continuously monitors the pH of the water. (Photo: Maria Cristina Gambi)

Go for a swim at the Castello Aragonese and follow the bubbles. The greater the amount of bubbles there are, the lower the pH level is. You will see as the pH lowers, there is a huge decrease in the number of species, and the sea turns from a beautiful, diverse environment to one dominated by brown/green algae. If we can reduce our emissions of carbon dioxide by choosing more sustainable methods, we can help prevent a future scenario like this.”



To visit the volcanic area with emissions of CO2 click

Article by PlatypusTour


Leave your comment