By, Rudy Bonn
Reef Relief’s Director of Marine Projects
When most people consider Climate Change, they fail to realize that most of Earth’s climate is significantly influenced by the salt water ocean that covers approximately 72% of the Earth’s surface to an average depth of over two miles. Winds, currents, precipitation, and other natural phenomenon are produced by the interaction of the Sun and its unique properties, and the world ocean and its unique properties.
For a simplified example, the hydrological cycle begins with the sun’s heating of oceanic waters; evaporation; rising and cooling; transport; condensing to form clouds; falling as rain; the water is then absorbed as groundwater or it runs off eventually reaching the ocean again, or it is released back into the atmosphere through transpiration and the cycle repeats itself.
Also, when people think of Climate Change, they think of carbon dioxide emissions, but fail to realize that the world ocean serves as a major carbon sink for all that carbon dioxide we are putting into the atmosphere. The world ocean absorbs 1/3 of all carbon dioxide presently being emitted into the atmosphere via man-made (anthropogenic) sources. The ocean is, at present, the largest carbon sink on the planet and it is becoming out of balance due to increasing levels of carbon dioxide.
In other words, the pH level in the world ocean is demonstrating an alarming trend towards becoming more acidic. pH, stands for potential hydrogen, and is the measure of hydrogen ion concentration. Fresh water as a pH of seven and is considered neutral, anything above 7 is considered to be more basic; anything below 7 is trending towards becoming more acidic.
In fact, a recent study suggests that by the year 2100, the pH of oceanic waters could fall by 0.5 units representing a three-fold increase in hydrogen ion concentrations; something that has not been observed for hundreds of millennia! The average pH of the world ocean is about 8; back in 1791, before the industrial age, the average pH was about 8.179. With the dawn of the 21st century, the net change was about -0.11, representing a 30% increase in hydrogen ion concentrations.
What does this mean? It means that ocean acidification is climate change’s evil twin. Animals like corals, pteropods, coccolithophores, diatoms, foraminiferans, and other calcifying organisms could be negatively impacted by dissolution as the result of falling pH levels in the world ocean.
Some of these organisms form the basis of marine food webs; others such as coral reefs provide habitat and food for as much as 25% of all ocean dwellers. Many nations, including ours and especially our own state of Florida depend upon healthy coral reef ecosystems.
It is even suggested that decreases in the pH of seawater could have an effect upon cloud cover over the surface of the Earth due to loss of coccolithophores in the surface waters and the effect that would have on the Earth’s albedo.
In case you are wondering, albedo is the measure of how strongly an object (earth in this case) reflects light from a light source such as the Sun!
What can we do? Well, we as individuals can learn ways to reduce our carbon footprints, and there are many ways in which to do so.