Sunday, February 28, 2016

Osteoporosis of the Ocean

This is a before and after picture due to Ocean Acidification. 

Ocean Acidification is a chemical process that denatures organisms like the corals. In chemistry, we learn that chemical processes are happening everywhere! In the ocean, higher pH near coral reefs help create chemical processes that form a calcium carbonate which is the process that coral grows and is built in such beautiful ways. Just as our body depends on calcium in our bones to hold us together for support, corals also need this calcification to become hard, stable, and sturdy. 

Now that we know why calcium carbonate is so important to corals, we can now discuss what ocean acidifcation is and why it is harming coral reefs. Ocean acidification denatures organisms like coral by decreasing the pH and basically dissolves the carbonate on corals by chemical processes irreversible because the water is too acidic to have a calcium carbonate coral. How can acidification occur in the ocean? What changes the pH to make it more acidic?

Increase in carbon dioxide in the atmosphere

An increase in carbon dioxide is all over the news in reference to climate change. Humans are burning fossil fuels and it is increasing the greenhouse gases in our atmosphere. A lot of those gases end up swallowed by the ocean and begins to change the chemistry in aquatic ecosystems. For example, the coral reefs are having a negative effect from increased carbon dioxide and increased acidity. 

In this study, they engineered a habitat replica of a coral reef (the Great Barrier to be specific) and mimicked the same alkalinity to test the results of increased or decreased alkalinity. One question they have been struggling to find a conclusion on is...

How much of an impact is ocean acidification having on coral reefs compared to warming of the ocean, pollution, or over-fishing?

They sought to decrease the alkalinity to a level that may have been present in coral reefs in the pre-industrial period. As they performed this test they found that a decrease in alkalinity in the manipulated reef was having a directly positive affect on the calcification rates in the corals. This study shows that acidification is having a direct affect on coral reefs quality of life and calcification rates. 

Many people argue about whether climate change is real, if carbon dioxide levels in the atmosphere are increasing, if it is caused by humans, or if it has potential to affect future generations. It is hard to see pictures like the one above and think that the earth just goes through cycles. The only way to help coral reefs increase in their calcification rates is by decreasing carbon dioxide levels in the atmosphere and in the ocean. Coral reefs no longer have the potential of dying, they are dying. Not only do coral reefs support a very bio-diverse marine ecosystem but they also prohibit waves swallowing islands, economic success from tourism and fishing. 

Below is a youtube video that touches on a lot of human related impacts on ocean biodiversity.


Carnegie Institution. "Ocean acidification already slowing coral reef growth." ScienceDaily. 24 February 2016.

1 comment:

  1. One topic we can explore further in class, or someone can cover in a presentation, is the physiological mechanism behind how corals accrete calcium carbonate and how this process is slowed by acidic waters.