When you hear about the problem with carbon dioxide, the first thing that comes to mind is probably global warming caused by the greenhouse effect. Another important aspect of the carbon dioxide problem is “ocean acidification.” In fact, there are a number of observation stations on the oceans to monitor the global marine environment. The topic of discussion at this Forum concerned ocean acidification, which is an issue of common concern for scientists, marine policymakers and industry professionals around the world.

On Monday, May 23^rd, the school hosted the 124^th GRIPS Forum, where a talk was given on the subject of “Another problem of CO₂: Ocean acidification and its impact on marine organisms.” The speaker was Dr. Naomi Harada, Deputy Director of the Research & Development Center for Global Change at the Japan Agency for Marine-Earth Science and Technology (JAMSTEC). Holding a Doctorate of Science, she is among the researchers in Japan investigating this problem with observation stations in the western sub-arctic of North Pacific and western Arctic Ocean.

Dr. Harada began her lecture by explaining the scientific aspects of the mechanisms behind the oceans’ acidification. She then talked about what real-world effects ocean acidification has on marine organisms, then traced back and analyzed the Earth’s history. Lastly, Dr. Harada presented a quantitative analysis of ocean acidification’s effects which she is working on at her research center.

Carbon Dioxide and the Mechanisms of Ocean Acidification

Dr. Harada showed an animation representing changes in carbon dioxide levels over the years. She emphasized that the gas’ current atmospheric concentration (400 ppm) is a level the Earth has not seen in the past 3 million years. When this carbon dioxide dissolves in the oceans and reacts with water, it creates a higher concentration of hydrogen ions and lowers the pH balance of the oceans, which normally maintain a steady alkalinity. This reaction is an acidification of the oceans. As it progresses, the oceans respond by trying to return to their original state due to buffer effect. In the process, an effect is exerted on the organisms dwelling in the seas, especially those that produce calcium carbonates, like plankton, coral and urchins.

Learning from the Earth’s History: An Era of Extreme CO₂ Concentrations

As a case study to find out how organisms react to this ocean acidification, Dr. Harada covered a period when the Earth experienced carbon dioxide levels comparable to today’s. The Paleocene-Eocene Thermal Maximum (PETM), which occurred approximately 55 million years ago, lasted a lengthy 1,000 years. It was a time when releases of methane gas produced extremely high concentrations of carbon dioxide. The results of an analysis on the seafloor sediment record show that negative damage was inflicted upon organisms that produce calcium carbonates, including the extinction of species in each of their ocean habitats. The findings also show that baseline production levels for organisms without calcium carbonate shells fell. Dr. Harada emphasized that it required an enormous amount of time–100,000 years–for the oceans to recover. Moreover, considering that carbon dioxide levels today are increasing at a terrible speed that is faster than any the Earth has ever experienced in its history, and that present conditions differ from the PETM period, as exemplified by changes in plankton communities due to their evolution, Dr. Harada explained the need for vigorous monitoring of how a great variety of species are responding to acidification.

Quantitative Analysis: The Impact on Calcium Carbonate Producers

In Dr. Harada’s group current research, her colleague is using x-rays to measure changes in the thickness and surface area of plankton shells in order to quantitatively analyze the impact that ocean acidification is having on the marine environment. An analysis to determine whether organisms which we call calcium carbonate producers will continue to make the chemical compound on into the future is the key to predicting the effect that ocean acidification will have on human society.

The strongest point that Dr. Harada made was that while ocean acidification gets little recognition among the public, it is a problem that will very directly affect the lives of individual people. At the conclusion of her talk, Dr. Harada provided sushi, a favorite dish among the Japanese, as an example to show that more than global warming or overfishing, ocean acidification will cause a greater drop in catches of shell fish used as toppings for sushi. This caught the interest of the audience. The impact will be immeasurable, affecting not only consumers, but also societies that will lose the services provided by the oceans, including those who work in the fishing and tourism industries.

Acidification is a fundamental problem for the oceans, which have no physical borders. Therefore, it is clear that cross-border cooperation is essential. GRIPS Vice President and Professor Atsushi Sunami, the facilitator for this Forum, noted that at the G7 Science and Technology Ministers’ Meeting held a few days prior, the member states reached an agreement to cooperate in monitoring the oceans, and he stressed that it is an international issue necessitating a greater policy response than at present.

When you hear about the problem with carbon dioxide, the first thing that comes to mind is probably global warming caused by the greenhouse effect. Another important aspect of the carbon dioxide problem is “ocean acidification.” In fact, there are a number of observation stations on the oceans to monitor the global marine environment. The topic of discussion at this Forum concerned ocean acidification, which is an issue of common concern for scientists, marine policymakers and industry professionals around the world.

On Monday, May 23^rd, the school hosted the 124^th GRIPS Forum, where a talk was given on the subject of “Another problem of CO₂: Ocean acidification and its impact on marine organisms.” The speaker was Dr. Naomi Harada, Deputy Director of the Research & Development Center for Global Change at the Japan Agency for Marine-Earth Science and Technology (JAMSTEC). Holding a Doctorate of Science, she is among the researchers in Japan investigating this problem with observation stations in the western sub-arctic of North Pacific and western Arctic Ocean.

Dr. Harada began her lecture by explaining the scientific aspects of the mechanisms behind the oceans’ acidification. She then talked about what real-world effects ocean acidification has on marine organisms, then traced back and analyzed the Earth’s history. Lastly, Dr. Harada presented a quantitative analysis of ocean acidification’s effects which she is working on at her research center.

Carbon Dioxide and the Mechanisms of Ocean Acidification

Dr. Harada showed an animation representing changes in carbon dioxide levels over the years. She emphasized that the gas’ current atmospheric concentration (400 ppm) is a level the Earth has not seen in the past 3 million years. When this carbon dioxide dissolves in the oceans and reacts with water, it creates a higher concentration of hydrogen ions and lowers the pH balance of the oceans, which normally maintain a steady alkalinity. This reaction is an acidification of the oceans. As it progresses, the oceans respond by trying to return to their original state due to buffer effect. In the process, an effect is exerted on the organisms dwelling in the seas, especially those that produce calcium carbonates, like plankton, coral and urchins.

Learning from the Earth’s History: An Era of Extreme CO₂ Concentrations

As a case study to find out how organisms react to this ocean acidification, Dr. Harada covered a period when the Earth experienced carbon dioxide levels comparable to today’s. The Paleocene-Eocene Thermal Maximum (PETM), which occurred approximately 55 million years ago, lasted a lengthy 1,000 years. It was a time when releases of methane gas produced extremely high concentrations of carbon dioxide. The results of an analysis on the seafloor sediment record show that negative damage was inflicted upon organisms that produce calcium carbonates, including the extinction of species in each of their ocean habitats. The findings also show that baseline production levels for organisms without calcium carbonate shells fell. Dr. Harada emphasized that it required an enormous amount of time–100,000 years–for the oceans to recover. Moreover, considering that carbon dioxide levels today are increasing at a terrible speed that is faster than any the Earth has ever experienced in its history, and that present conditions differ from the PETM period, as exemplified by changes in plankton communities due to their evolution, Dr. Harada explained the need for vigorous monitoring of how a great variety of species are responding to acidification.

Quantitative Analysis: The Impact on Calcium Carbonate Producers

In Dr. Harada’s group current research, her colleague is using x-rays to measure changes in the thickness and surface area of plankton shells in order to quantitatively analyze the impact that ocean acidification is having on the marine environment. An analysis to determine whether organisms which we call calcium carbonate producers will continue to make the chemical compound on into the future is the key to predicting the effect that ocean acidification will have on human society.

The strongest point that Dr. Harada made was that while ocean acidification gets little recognition among the public, it is a problem that will very directly affect the lives of individual people. At the conclusion of her talk, Dr. Harada provided sushi, a favorite dish among the Japanese, as an example to show that more than global warming or overfishing, ocean acidification will cause a greater drop in catches of shell fish used as toppings for sushi. This caught the interest of the audience. The impact will be immeasurable, affecting not only consumers, but also societies that will lose the services provided by the oceans, including those who work in the fishing and tourism industries.

Acidification is a fundamental problem for the oceans, which have no physical borders. Therefore, it is clear that cross-border cooperation is essential. GRIPS Vice President and Professor Atsushi Sunami, the facilitator for this Forum, noted that at the G7 Science and Technology Ministers’ Meeting held a few days prior, the member states reached an agreement to cooperate in monitoring the oceans, and he stressed that it is an international issue necessitating a greater policy response than at present.