Here are the basic points relating to the chemistry of ocean acidification.
Cartoon illustration of ocean acidification processes by Pacific Marine Environmental Lab
You can think of pH as standing for the “Power of Hydrogen”. The lower the pH, the more hydrogen ions and the fewer hydroxide ions there are. Remember that this is a logarithmic scale, so small changes in number reflect big changes.
Carbon dioxide and temperature variations over the past 800,000 years.
Recent trends observed in atmospheric carbon dioxide (red), oceanic carbon dioxide (dark blue) and pH (light blue) observed at Hawaii’s Mauna Loa and Aloha observatories
Per-person uptake of carbon dioxide by the oceans.
Our current unprecedented rate of marine ecosystem change.
Coral reefs are tremendously valuable natural assets, which protect coastal zones from damaging storms and act as the nurseries of the sea.
Carbon dioxide concentration levels at which coral reefs stop growing and start dissolving, in context of various projected trends in carbon dioxide emissions.
The past and two possible futures for oceanic pH.
The past and possible future maps of ocean pH.
Past and possible future maps of Aragonite saturation state. Values below 1 were corrosive to corals and shellfish.
Map of past Aragonite saturation state. Values below 1 are corrosive to corals and shellfish.
Possible future map of Aragonite saturation state. Values below 1 were corrosive to corals and shellfish.
Varieties of cocolithophore phytoplankton raised at 300 parts per mission of carbon dioxide (upper row) and 800 parts per million (lower row).
Pteropods, also known as butterfly snails, are an important part of the marine food web.
If we don’t change course, pteropods will dissolve in conditions predicted for the Southern Ocean by the end of this century.
One day old oyster from the same parents hatched in favourable and unfavourable pH environments.
Magnified images of some of the many varieties of plankton that could be affected by changes to ocean pH.
Porcelain crabs metabolism and behaviours changed when exposed to predicted higher levels of pH and low-tide temperatures.
Global economic impacts of losing shellfish aquaculture may amount to $130 billion / year by 2100 — if we don’t change course.
Changes to phytoplankton communities may have significant and unpredictable impacts on global fisheries.
We’re changing the basic rules for everything, and because of this, many marine organisms may not survive.
Words of warning by Dr. James Hanson.
There are some very powerful entrenched interests that wish to keep the fossil fuel status quo, but the power of the people is rising.
Dwight Owens – “Sour Seas: ocean acidification explained”
by Andrew Bryant, 21 February 2016
Dwight Owens works for Ocean Networks Canada, where he serves as a “user engagement officer”. Although not a scientist himself, Dwight’s mandate is to help make recent scientific research accessible to the general public. This he did – in spades!
He spoke to us about ocean acidification, which has been called “global warming’s evil twin”. Using graphics gleaned from a wide variety of sources, Dwight provided a lively introduction to a very sobering topic.
Why are oceans becoming more acidic, and what impacts can we expect? Dwight discussed recent and projected changes, examining impacts on marine ecosystems and human society.
For those interested in learning more about this fascinating, although frightening, topic, Dwight also provided a help link to many on-line sources, which can be found here.
