Carbonated Oceans (2021 Version)
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- Опубліковано 5 вер 2021
- For an introductory college-level oceanography class. Review of the sources, sinks, and impacts of carbon dioxide dissolved in the oceans.
**This video comes near the middle of the semester, so there may be terms with which the audience is unfamiliar. For a full playlist, refer to the Oceanography playlist on the Earth Rocks! UA-cam Channel.
Content within this video is based on information available in any standard introductory college oceanography textbook, such as Essentials of Oceanography -- Trujillo and Thurman - Pearson Publishing.
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2021 Version. Revisions were necessary because the data on carbon dioxide levels in the oceans has improved -- we have a better idea now of how carbon dioxide varies with depth worldwide. Also, the amount of carbon dioxide in our atmosphere went from 350 ppm when video was first published in February 2015 to over 400 ppm in 2021.
An excellent presentation. Warmer oceans will hold less CO2. Land plants will benefit... if we stop destroying their water availabilty by removing forests.
I'm glad you liked it. Thanks for letting me know. Yes, whenever resources are diverted from one location to another, there are both benefits and harms -- it all depends which area you look at.
I really would like to see you revisit minerals and rocks etc... I love your videos and that area particularly seems to be a strong suit of yours in views. Whatever you do, keep posting content! The time is now for information!
I can’t believe I’m so interested in the stuff I was so unenthusiastic to learn when I was actually taking the class, and now I love learning it
Awesome! :)
A question: during the Cretaceous period a lot of limestone was laid down (ie. White Cliffs of Dover,), due to an abundance of coccoliths a calcium carbonate based critter, yet there was apparently high levels of Co2 in the atmosphere. Should this have not made the oceans very acidic hence destroying any calcium based organism. I have never figured out this conundrum.
Good question. I'm not sure, but let me throw out some ideas.
Firstly: CO2 in the atmosphere in the Cretaceous was higher than during the ice age times, but much lower than it is today (we've surpassed anything we've seen in Earth's history). Also the oceans would have been warmer as overall global temperatures were 10°C higher than today. So that would have meant over lower CO2 values in the oceans than we see today.
Secondly: pH is the oceans, on average, is 8.1, but the highest numbers are in the warmer surface waters where CO2 is lowest, and the smallest numbers (most acidic) is in the deeper waters that are colder and higher pressure.
Coccolithophores and other calcium-carbonate-shelled organisms living in surface waters would have done just fine. Their shells would have accumulated in large amounts in any waters shallower than probably 5-6,000 m. That gave them plenty of space to accumulate on the ocean floor and continental shelves.
I hope that helps! :)
This is very good. In the beginning, I had trouble visualizing the H2O combining with the CO2. The manual removal of the atoms made the structural chemical changes much more clear. A small point for me was that I had trouble mentally maintaining the data of which color was which atom. I know that the color was arbitrary. But for a demo, it would add to my understanding to use a marker to draw the letters C, H, O on the atoms so it could always be seen. I have a more visual memory than verbal memory. Thanks.
Good feedback. Thanks! :)
Excellent video!!
Glad you liked it!
The pH scale is log so every whole number is a power/factor of ten.
By definition pH is the negative exponent of the hydrogen ion concentration.
For instance, pH 9 is 10^-9 or 1 part per billion, 0.000000001.
pH 8 is 10^-8 or 10 parts per billion, 0.000000010.
To go from pH 9 to pH 8 is factor of 10 or 1,000%!!!! Makes 26% look trivial.
Ocean “acidification” of pH 8.2 to pH 8.1 is a decrease in alkalinity equal to 1 ppb of H ions.
I’m fairly certain the ocean flora and fauna don’t even notice.
As far as I can tell from current research, some fauna are noticing -- but in localized areas, and it's not yet clear how much of an impact it's having. Work has been done on populations of oysters in the Puget Sound and Blue Crab larvae in Chesapeake Bay.
Very well done. May I make a couple of observations? First, the most important gas dissolved in the ocean is not carbon dioxide. That's a political statement. If CO2 were to rise in the ocean, the excess would quickly combine with calcium ions and precipitate as lime . . . hence all the mountains of the earth made of limestone, dolomite and marble. Oxygen is the most important gas dissolved in ocean water. Without oxygen all fish would die within minutes. Second, calcium carbonate (the stuff shells are made of) as well as much of the ocean floor "sand", acts as a buffer or regulator of the ocean's acid or pH. Carbon dioxide is simply along for the ride, which is a short ride because of the huge amount of calcium ions in ocean water (again, ready to combine with the carbonic ions and form lime and quickly settle to the ocean floor and become limestone). Most mountain ranges on earth's dry land areas are made of limestone. That means these rocks were once atmospheric carbon dioxide combined with dissolved calcium (limestone and marble are made of calcium carbonate) sitting at the bottom of the oceans. And that's earth's natural buffer and "filter", naturally removing carbon dioxide from the atmosphere and storing it for eons of time as rocks (limestone, dolomite and marble) with no governmental subsidies or fossil fuel pipeline disruption. Thanks for posting, and . . . YES . . .I am a new subscriber.
Richard -- good point on the "most important" gas -- I should have said "most abundant" and left any judgment off. I'll make that note for next version. Each gas in the oceans is important, for a variety of reasons. Good editing note. Thanks.
@@EarthRocks Thanks for the response. I fully understand that your posts must contain supportive comments about "climate change" and the evils of carbon dioxide, otherwise it may be deleted by YT "Fact Checkers".
that's a lot to take in for a laymen but I think I get it ,thank you
Indeed it is! The video requires a lot of previous knowledge as it comes midway through an Oceanography class. Glad you got something out of it. :)
"(AMOC) has weakened by 15-20% in 200 years", that's the flow and vertical churn of ocean waters.
Doesn't ocean slowing mean warmer upper waters that absorb less heat and leaving more CO2 in the air or even emitting CO2 into the air more often?
The world uses 745,162 pounds of fertilizer on farms per minute (worldfoodclock), and since much of it is nitrogen fertilizer which acidifies and is running off into the oceans eventually, shouldn't we be expecting to see a really dramatic ocean pH change to far less alkaline than the current pH 8.11 vs historical values going back hundreds and thousands of years?
Good questions.
Yes on first part. As the surface waters of the world's oceans warm, it does mean less CO2 can be absorbed.
As for your other question: nitrogen fertilizers in the water systems leads to increased phytoplankton and seaweed/algae growth because it's a nutrient. It is true that in the atmosphere, you can get nitrous oxides and acid rains, but that doesn't have a noticeable impact on the oceans, likely because the high amounts of CO2 act as a buffer and undo any additions of H+. I'm not aware of any nitrogen in the oceans leading to pH changes.
@@EarthRocks Hold on. CO2 alkalinizes oceans? I'm sure you didn't mean that in ... "likely because the high amounts of CO2 act as a buffer and undo any additions of H+".
Nitrogen fertilizer runs off of expanding farmlands into oceans, increasing algae, creating dead zones (reduced oxygen). I presume we're on the same page so far. " _Between 1970 and 2005 the amount of nitrogen fertilizer alone, applied globally, increased by almost a factor of three_ " [one thousand times higher]. (worldoceanreview) That article doesn't mention CO2. Plenty of sources talk about acidification by nitrogen fertilizer but it is complex, maybe worth a video itself. pH up or down? Yes and no. Confused? Somewhat. By the way I'm talking runoff of applied fertilizers, like even from irrigation, 745,162 pounds per minute, not air pollution.
But if we carbonate a quart of water, adding CO2, it's going to be--what--maybe pH 4 (acidic), like soda pop, no? Then add nitrogen fertilizer to another quart of water and perhaps it might be pH 2? Mix them together and get pH 3? Thus CO2 has buffered the fertilizer from 2 to 3? Perhaps that is what you're saying, I don't know. [Edit: More in the direction of 2.5 (from 2.0) due to the logarithmic scale I guess]
Meanwhile it would not surprise me if ocean mammals seek refuge from dead zones where at least they can get some oxygen from the air -- on beaches. Frankly I think we humans are more interested in fertilizing impressions of our chosen narratives than connecting dots in reality, sorry to say. So we come along and push them back out into the dead zone.