Ocean acidification: a climate change issue

The vast expanse of icy white stretches over the horizon as Brad Seibel and his National Science Foundation team of scientists step out of their shelters to begin the new day.

Seibel is a professor of Biological Sciences at the University of Rhode Island. He is also a comparative animal physiologist and specializes in the physiology of marine animals in extreme environments.

The four-person team has traveled to Antarctica to study the “trade-off between aerobic capacity and locomotory activity in an Antarctic pteropod.”

In other words, the team observes how sea snails—also known as sea butterflies because of their ability to “fly” through the water—adapt to cold temperatures, low oxygen levels or high carbon dioxide levels. Cold waters accelerate the dynamic between their respiratory functions and physical activity, which makes the −1.8 °C Antarctic waters an optimal research location.

This study was prompted by increasing evidence and research that the ocean’s acidity level or pH is changing drastically due to the excessive amount of carbon dioxide emissions produced by human interference and influence. This process is known as ocean acidification and holds severe ramifications for the future of both the oceans and its vibrant, yet fragile residents.

Since the Industrial Revolution in the mid-eighteenth century, human’s agricultural and industrial activities have caused carbon dioxide concentrations in the atmosphere to increase from 280 to 387 parts per million (ppm). Almost half of this rise has occurred in the last 30 years.

Most scientists agree that this problem is mostly derived from human emissions. By 2050, atmospheric carbon dioxide levels are estimated to reach more than 500 ppm and possibly 800 by 2100. Earth’s history confirms that oceans have acidified in the past but the main difference from past acidic events is the rate of change. The last time ocean’s acidification levels were this high was 56 million years ago.

Oceans, rivers, lakes and other major bodies of water absorb about 25 percent of the carbon dioxide in the atmosphere each year, roughly 22 million tons a day. Interestingly, this has helped curb the effect of climate change by removing some of the carbon dioxide that would have ended up in the air and instead storing it in the oceans.

However, this extra carbon dioxide in the water has increased the acidity of global waters to an unnatural point. Acidity is measured by the pH scale, which determines the acidity or alkalinity of an aqueous solution on a scale between 0 and 14.

A lower pH level means more acidic. Current and future continued acidification of the ocean will increase the current pH level by 0.3 to 0.4 by the end of the century.

If environmental changes happen slowly enough, species have the chance for their evolutionary processes to catch up with these changes. Evolutionary adaptation used to be enough for marine organisms to keep up with environmental changes but now humans have expediated the process to the point that marine organisms can no longer keep up.

“When things happen really rapidly, big extinction happens,” says Chris Langdon, Professor of Marine Biology and Fisheries at University of Miami. Langdon specializes in tropical marine ecology, which includes going out into the field and studying mangroves, coral reefs and sea grass.

Langdon believes these ecosystems are especially sensitive to climate change. He spends most of his time out in the reefs of the Florida Keys, bringing back test samples to his laboratory at the Rosenstiel School of Marine and Atmospheric Science.

Here, he puts them in the aquarium tanks where he can control the temperature and pH of the water to simulate present day conditions that he and his fellow scientists think will be experienced in the next 50 to 100 years.

Laura Sanchez Ubanell, Voxxi, 21 December 2013. Full article.

1 Response to “Ocean acidification: a climate change issue”

  1. 1 Jean-Pierre Gattuso 23 December 2013 at 13:09

    The title of this article is misleading because ocean acidification is not a climate change issue. Ocean acidification and climate change share the same cause, the increase in CO2 in the atmosphere, but are (almost) independent processes.

    Jean-Pierre Gattuso

Comments are currently closed.

  • Reset


OA-ICC Highlights

%d bloggers like this: