Ocean Acidification

In this video Paul Andersen shows how carbon dioxide in the atmosphere is causing a decrease in the pH of the oceans. The carbon dioxide combines with the water to create carbonic acid which dissociates into bicarbonate and carbonate anions. Decreased pH leads to lower metabolism and immune response in marine species. Increased bicarbonate makes it difficult to form shells and reefs of calcium carbonate.

Music Attribution

Intro
Artist: CosmicD
Creative Commons Atribution License

Outro
Title: String Theory
Artist: Herman Jolly

All of the images are licensed under creative commons and public domain licensing:

[katedwek]

You just explained the chemistry part of Ocean Acidification in a way I understand and will actually remember. Please never stop teaching.

[BigCumDaddy-Incher]

I unironically watched this video when i was in high school. Now Im watching it again for an Ecology presentation! Youre the best!

[henrygao]

Took a selfie with you when you came to Shanghai. Glad to see that you are making videos again!

[seanallen]

So pumped you just came out with this. I just taught my ocean acidification lab on it to my class earlier today.

[wildlifeanimated]

It's great to see videos like this bringing ocean acidification into the public's eye. Once people are aware of what's happening, they can take action. Communities that support public transport systems, alternative energy sources, and other projects like bike sharing programs provide awesome examples of what can be done to reduce CO2 emissions!

[cvolpano]

Thank you for your breakdowns of topics. Looking at scientific literature is much easier with a broad understanding to start.

[Cgraseck]

This is the best explanation of the carbonate bicarbonate balance being shifted by carbon dioxide that I have ever seen.
Thanks,
Chris

[CopingsCorner]

This is problem cannot be overestimated. I addressed that even though we could hypothetically build orbital solar shades to cool down the planet (implicit ofc solar dimming), this would not prevent ocean acidification, and so CO2 has to be dealt with regardless.
So glad I found this channel again after changing accounts, but even more glad to see how large it has grown. 1mill coming soon :D

[dmartinezkc]

Clarification question: In the Bjerrum graph, it depicts Carbonic acid at its peak when oceans are more acidic, and carbonate when oceans are more basic. However if it's an increase in H+ ions that causes oceans to become more acidic, should we get an very acidic ocean when carbonate is at its peak, rather than carbonic acid? I would have thought that lots of carbonate means lots of dissociated H+ ions floating around making the ocean more acidic. I'm sure I'm just missing something here.

Thanks, great video!

[klarissasimpson]

So helpful! Thankyou so much, the diagrams of the loss of H+ ions really helped.

[OldScientist]

As regards ocean acidification, it is estimated that the ocean’s global mean surface pH may have declined (i.e., become less alkaline and thus more “acidic”) by -0.07 to -0.08 in the last 200 years — from pH8.12 during pre-industrial times to 8.04 to 8.05 today (Wei et al, 2015). N.B. The decline in pH occurred before 1930.
However, and very importantly when you look the data after CO2 emissions began rising precipitously in the 1930s, the oceans have become less “acidic”!!!
By way of comparison, from one season to the next, or over the course of less than 6 months, pH levels naturally change by ±0.15 pH units, or twice the overall rate of the last 200 years. On a per-decade scale, the changes are even more pronounced. Oceanic pH values naturally fluctuate up and down by up to 0.6 U within a span of a decade, with an overall range between 7.66 and 8.40. This is decadal rate of pH change is larger than the overall 200-year span (0.07-0.08) by a factor of 8.

[dismantledbrain]

If anyone is wondering how does more CO2 mean less CO3 when it's the final result of the equation, you have to remember that CO3 plays a role in the buffer system, and along with H+ will give HCO3.
That means the more CO2 you add, you will also be losing more CO3 in favor of HCO3.

Hope this is helpful.

[bradkeen]

The pH of the oceans in 1751 was 8.25? How do you know that? The concept of pH wasn't discovered till 1909 and reliable testing till 1924. Trouble is that pH can only be measured in real time.

Second, the solubility of CO2 in water decreases as water temp increases. To take his soda stream experiment, chilled water keeps bubbles longer.

Third, the experiments you see with sea shells disolving in water don't tell you one thing. They adjust pH down by adding hydrochloric acid. Of course sea life and this chlorine compound don't mix.

[sebastianjovancic]

Increased carbon dioxide will lead to increased surface temperature which decreases solubility of carbon dioxide on oceans, so I believe we are missing pieces here, and saying CO2 decreases alone are a solution is reductionist, I'd imagine

[leonstenutz]

Outstanding! A masterpiece of science communication. Thank you!

[operator]

"This is often termed “ocean acidification” because it describes the process of decreasing pH. Current projections of ocean acidification suggest that the pH of surface ocean waters will continue to decline. However, the term can also lead to confusion when it is wrongly assumed that the oceans will become acidic, when in reality, ocean pH is never expected to fall below 7.0; i.e., the oceans are becoming less basic, but not acidic. Such a phenomenon could only occur in the unlikely event that CO2 emissions reach more than 10, 000 Pg C (Caldeira and Wickett, 2005)"

[alexs.]

Thanks for making this video! It is pretty surprising how ocean acidification is never talked about despite it being a large issue.

[fhksr]

You are really good teacher. You give me inspiration for learning about the science
and every student should be aware of this videos. Thank you. :)

[Louis]

Three relevant points:
1. The pH scale was created in 1909 by Danish chemist S. P. L. Sørensen. We have no idea of the pH of the oceans in 1751.
2. The solubility of CO2 in water is strictly/rigidly controlled by temperature. Cold water holds 5x as much as warm. Our cold oceans (from the last ice age) are saturated with CO2, and are gradually releasing it as they warm. This is the primary cause of rising CO2 levels today.
3. Human activities only account for ~3.6% of the total amount of CO2 released annually.

[leahb]

Hi! your videos get me through every science subject I need to go through and to even enjoy it more! Impacts of the animal industry in relation to global warming and ocean acidification would be a great topic to speak about. Sharing ideas on how to lower our impact through our actions relating it to the science would promote great awareness to all of your watchers! Thanks for you great work!!