It really shows the importance impact of even the Slightest differences in a given environment. Temperature, density, pressure, salinity, charge, etc. Etc.
I welcome increased knowledge of earth’s inherent mechanisms particularly in concern to atmospheric change which changes all of our lives. Thank you for this excellent presentation.
This is really excellent, I learned a lot, many kind thanks! Ocean salinity is crucial for accurate climate modeling e.g. freshwater inputs, as salinity influences ocean circulation patterns. This is still not well known and may be an interesting future topic. Again many thanks, keep going!
I love how you reinforce previous concepts by quickly and succinctly defining them again (e.g. how earth got its oceans--I was starting to forget it but that one slide brought it all back). Spaced repetition for the win 👍🏻
Thank you Dr.Rachel for such an incredible knowledge share I have a question from your past videos "Given the prevalence of large-sized pisovoids and ovoids in Precambrian ages due to the closer proximity of the moon to Earth, what factors contributed to their abundance in Jurassic rocks".
Love your videos and have been learning a lot. I was hoping to see a chart of how much the ocean chemistry has changed over geologic time scales, and maybe something of how that affected life. You also had me expecting some quantification of the Co2/O2/N2 ratios in the surface ocean to compare to the atmospheric ratios you quoted. Still, I learned a ton. Thank you!
The ocean composition and concentrations of O2 CO2 and N2 are very hard to put a global average on since they vary super drastically, both spatially in coastal vs open ocean regions (due to coastal algal blooms) and also in depth (due to CO2 uptake and O2 release at the surface from photosynthesis, and O2 uptake and CO2 release at depth from decomposition), so there any 'averages' really mean nothing on a local or even regional scale since it depends so heavily on the biological productivity of the region, and that's why I didn't quantify them ;) Hope that makes sense! That said: I do have videos discussing ocean chemistry through time (specifically ocean oxygen concentrations, if you want to check them out!). See below videos on: Ocean oxygenation and its relation to animal evolution: ruclips.net/video/nhKYFjNpDLM/видео.html How continental rearrangement affects ocean oxygen concentrations: ruclips.net/video/G_T7xYu6Smc/видео.html The great oxidation event (first major rise in oxygen): ruclips.net/video/LK6X3EGEdOY/видео.html The neoproterozoic oxygenation event (a second major oxygen rise): ruclips.net/video/vcCkU2qtBQU/видео.html Paleozoic oxygen fluctuations & their effects: ruclips.net/video/oPX0rBTYG8g/видео.html
At about 9:36 you mention manganese a couple of times. I think you meant magnesium. I only mention this because calcite can also contain trace amounts of manganese, but I think not enough to affect aragonite/calcite biochemical processes throughout time.
I fear the oceans may be reaching their breaking point in the ability to absorb excess heat and CO2 from the atmosphere as a result of our fossil fuel use. 'Tipping point' comes to mind. I enjoy these Sunday Geography lessons. Very well presented for the layman. The link between past volcanism and Mg/Ca ratios in marine organisms was particularly interesting. The clues available for determining paleoclimate are just fascinating.
Yes! Oceans absorb 93,4% of global warming ans ~25% of the CO2 we emit. When we say the globe has warmed by 1,5°C, we actually ignore 97,7% of the warming, IPCC AR4 from 2007 had a cartoon of the components of global warming qhich shows that the atmosphere (actually the troposphere) takes up only 2,3% of the warming.
I think it only locally affects where the salt is dumped, unless they gather and sell the salt to sell it. I actually don't know what they do with it. 🤷♂ Interesting question though 👍
Since phytoplankton are responsible for more than 50% of co2 to oxygen I am really Looking forward to a video about phytoplankton and Nasa Pace mission
Inquiring about the eutrophication of oceans during the Cretaceous strata, could the smaller distance between the Earth and the Sun due to Milankovitch cycles have been a contributing factor?
You mentioned percentages of gases in the air (N, O2, CO2), but you didn't mention the concentration of CO2 in the upper levels of the ocean. Does the concentration differ in different parts of the world so that there's no one percentage that truly defines CO2 in the upper ocean?
Yes absolutely! The upper ocean CO2 concentrations vary widely depending on whether there are algal blooms in that region, whether there is upwelling (vertical mixing) bringing CO2 from the deep water to the surface or if it stratified so that the surface water is relatively depleted in CO2, etc. There are so many local and regional factors that affect CO2 in the upper ocean that is not really possible to put an average on it in terms of global concentration ;)
Thank you for great science. I would like to see more videos on the science (ie iron oxide, isotopes,ect.) on determining ancient climates,atmosphere, extinction events. Thanks
Thanks! Check out my 'how we study Earth's past' video: ruclips.net/video/J9Te_sGZ_c0/видео.html in which I cover a whole bunch of ways (isotopes & other chemical, physical and biological signatures in rocks) that we reconstruct ancient climates, conditions, and extinctions! ;)
A question... It sounds like there's some ability to date limestones based on how much Mg is in them. Is this new, or is it limited, or am I over-guessing how much can be determined? I had the impression that limestone can't normally be dated. (I'm thinking partly of some of the way it's hard to tell Kaskaskia sequence limestones apart from Tippecanoe sequence ones, partly just in general about the possibility of direct dating for more stratigraphic layers in general)
"Considering the shift from high Mg: Ca ratios favoring calcite in the Permian to low Mg: Ca ratios favoring aragonite today, what geological processes might explain this transition?"
It would be great to get a video from you on the carbonate system of the ocean, which buffers its pH. We wonder if the ocean was really that much more acidic hundreds of millions of years ago when atmospheric CO2 was a multiple of today’s concentration, i.e. ~2000 parts per million. As you said in this video there is a lot of interaction between the rocks and the ocean, and microbes weather that rock, especially serpentine which contains hydrogen. We are rather baffled by the idea promoted by most oceanographers that atmospheric CO2 determines ocean pH, and not the ocean crust which is full of convection currents.
My other question is "Exploring the paradox of BIF (Banded Iron Formation) formation during the Snowball Earth event, considering its reddish Fe-rich nature typically associated with intense chemical weathering processes".
I'm not sure that would be predominantly chemical weathering. Having a large number of glaciers/ice sheets on Earth would I think cause a lot of mechanical weathering and erosion. (The ice grinds down the surface and caries that to the oceans.)
Dear @@jimthain8777 Could the reddish tint seen in Banded Iron Formations be linked to periods of Snowball Earth, suggesting a connection between extreme glaciation events and alterations in iron mineral composition?
I always enjoy your content, Rachel, thank you. However, I wonder why your references are only books, instead of supplemented by research papers 🗞️ as well? I think that complementing textbook references with research would provide more depth, novelty, and perspective to your content.
Excellent DR GEO GIRL
It really shows the importance impact of even the Slightest differences in a given environment. Temperature, density, pressure, salinity, charge, etc. Etc.
Thank you Rachel for your videos and sharing your knowledge.
Thanks!
Thank you so much!
Another superb video!
I welcome increased knowledge of earth’s inherent mechanisms particularly in concern to atmospheric change which changes all of our lives. Thank you for this excellent presentation.
Very well done and explained wonderfully. Thanks for doing what you do.
This is really excellent, I learned a lot, many kind thanks! Ocean salinity is crucial for accurate climate modeling e.g. freshwater inputs, as salinity influences ocean circulation patterns. This is still not well known and may be an interesting future topic. Again many thanks, keep going!
I love how you reinforce previous concepts by quickly and succinctly defining them again (e.g. how earth got its oceans--I was starting to forget it but that one slide brought it all back). Spaced repetition for the win 👍🏻
I had to pause and back-track a number of times to sort those competing relational interactions Ms GG.
Thanks for another spectacular vid.
Thank you Dr.Rachel for such an incredible knowledge share I have a question from your past videos "Given the prevalence of large-sized pisovoids and ovoids in Precambrian ages due to the closer proximity of the moon to Earth, what factors contributed to their abundance in Jurassic rocks".
Sigh, poor corals can't catch a break! Informative and sobering as usual, thanks Rachel.
Love your videos and have been learning a lot. I was hoping to see a chart of how much the ocean chemistry has changed over geologic time scales, and maybe something of how that affected life. You also had me expecting some quantification of the Co2/O2/N2 ratios in the surface ocean to compare to the atmospheric ratios you quoted. Still, I learned a ton. Thank you!
The ocean composition and concentrations of O2 CO2 and N2 are very hard to put a global average on since they vary super drastically, both spatially in coastal vs open ocean regions (due to coastal algal blooms) and also in depth (due to CO2 uptake and O2 release at the surface from photosynthesis, and O2 uptake and CO2 release at depth from decomposition), so there any 'averages' really mean nothing on a local or even regional scale since it depends so heavily on the biological productivity of the region, and that's why I didn't quantify them ;) Hope that makes sense!
That said: I do have videos discussing ocean chemistry through time (specifically ocean oxygen concentrations, if you want to check them out!). See below videos on:
Ocean oxygenation and its relation to animal evolution: ruclips.net/video/nhKYFjNpDLM/видео.html
How continental rearrangement affects ocean oxygen concentrations: ruclips.net/video/G_T7xYu6Smc/видео.html
The great oxidation event (first major rise in oxygen): ruclips.net/video/LK6X3EGEdOY/видео.html
The neoproterozoic oxygenation event (a second major oxygen rise): ruclips.net/video/vcCkU2qtBQU/видео.html
Paleozoic oxygen fluctuations & their effects: ruclips.net/video/oPX0rBTYG8g/видео.html
"Water: the universal solvent" (given enough time of course)
If I'm here, it's because you do excellent work Doctor Rachel 👍
Awesome!👍
Where was this in my college oceanography class? 😂
Love this❤
Thanks! great lesson! cheers from Brasil!
Please Dr.Rachel make a video on the Biomarker analysis TEX86 and how they are related to the proxy for Paleoclimate analysis.
At about 9:36 you mention manganese a couple of times. I think you meant magnesium. I only mention this because calcite can also contain trace amounts of manganese, but I think not enough to affect aragonite/calcite biochemical processes throughout time.
My bad! I always accidentally say Mn when I mean Mg 😅 thanks for catching that!
Rachel ⛳,
Thank you 🙏 for this fascinating video 🎬. Keep up the good work!
Thanks a lot!
I fear the oceans may be reaching their breaking point in the ability to absorb excess heat and CO2 from the atmosphere as a result of our fossil fuel use. 'Tipping point' comes to mind. I enjoy these Sunday Geography lessons. Very well presented for the layman. The link between past volcanism and Mg/Ca ratios in marine organisms was particularly interesting. The clues available for determining paleoclimate are just fascinating.
Yes! Oceans absorb 93,4% of global warming ans ~25% of the CO2 we emit.
When we say the globe has warmed by 1,5°C, we actually ignore 97,7% of the warming, IPCC AR4 from 2007 had a cartoon of the components of global warming qhich shows that the atmosphere (actually the troposphere) takes up only 2,3% of the warming.
😁 Nice!
Thanks again.
I can only imagine your classes full of very happy students.
Haha! I think some of them are very happy! I think others are indifferent lol, but just as long as none of them are unhappy that's my goal! ;)
How does Dr. Geogirl know im in Oceanography right now 😮
great content!
Thank you! ;D
🐰 Thanks Doc
doc, great video. what about the massive purification of sea water in the middle east is trying do? how does affect the sea water chemistry?
I think it only locally affects where the salt is dumped, unless they gather and sell the salt to sell it. I actually don't know what they do with it. 🤷♂
Interesting question though 👍
@@a.randomjack6661 tyvm. a very good answer.
In regards to salinity of inland seas, Rachel, there are parts of the Baltic Sea where the salinity is so low the water is drinkable.
Since phytoplankton are responsible for more than 50% of co2 to oxygen I am really Looking forward to a video about phytoplankton and Nasa Pace mission
Seconded!
Thirded 👍
Fourthed!
Inquiring about the eutrophication of oceans during the Cretaceous strata, could the smaller distance between the Earth and the Sun due to Milankovitch cycles have been a contributing factor?
Knowledge is good, try a little bit of good editing, and boom you go viral ❤
Haha, yea I know I am not the best editor, but I just try to get a little better with each video, so maybe someday I'll be good lol ;)
@@GEOGIRLdo-learn-do! Love the thoughtful effort you put in to targeting young people.
You mentioned percentages of gases in the air (N, O2, CO2), but you didn't mention the concentration of CO2 in the upper levels of the ocean. Does the concentration differ in different parts of the world so that there's no one percentage that truly defines CO2 in the upper ocean?
Yes absolutely! The upper ocean CO2 concentrations vary widely depending on whether there are algal blooms in that region, whether there is upwelling (vertical mixing) bringing CO2 from the deep water to the surface or if it stratified so that the surface water is relatively depleted in CO2, etc. There are so many local and regional factors that affect CO2 in the upper ocean that is not really possible to put an average on it in terms of global concentration ;)
Thank you for great science. I would like to see more videos on the science (ie iron oxide, isotopes,ect.) on determining ancient climates,atmosphere, extinction events. Thanks
Thanks! Check out my 'how we study Earth's past' video: ruclips.net/video/J9Te_sGZ_c0/видео.html in which I cover a whole bunch of ways (isotopes & other chemical, physical and biological signatures in rocks) that we reconstruct ancient climates, conditions, and extinctions! ;)
A question... It sounds like there's some ability to date limestones based on how much Mg is in them. Is this new, or is it limited, or am I over-guessing how much can be determined? I had the impression that limestone can't normally be dated. (I'm thinking partly of some of the way it's hard to tell Kaskaskia sequence limestones apart from Tippecanoe sequence ones, partly just in general about the possibility of direct dating for more stratigraphic layers in general)
"Considering the shift from high Mg: Ca ratios favoring calcite in the Permian to low Mg: Ca ratios favoring aragonite today, what geological processes might explain this transition?"
It would be great to get a video from you on the carbonate system of the ocean, which buffers its pH. We wonder if the ocean was really that much more acidic hundreds of millions of years ago when atmospheric CO2 was a multiple of today’s concentration, i.e. ~2000 parts per million. As you said in this video there is a lot of interaction between the rocks and the ocean, and microbes weather that rock, especially serpentine which contains hydrogen. We are rather baffled by the idea promoted by most oceanographers that atmospheric CO2 determines ocean pH, and not the ocean crust which is full of convection currents.
My other question is "Exploring the paradox of BIF (Banded Iron Formation) formation during the Snowball Earth event, considering its reddish Fe-rich nature typically associated with intense chemical weathering processes".
I'm not sure that would be predominantly chemical weathering. Having a large number of glaciers/ice sheets on Earth would I think cause a lot of mechanical weathering and erosion. (The ice grinds down the surface and caries that to the oceans.)
Dear @@jimthain8777 Could the reddish tint seen in Banded Iron Formations be linked to periods of Snowball Earth, suggesting a connection between extreme glaciation events and alterations in iron mineral composition?
Just “How Salty” is the “Ocean?” 😅
Seawater is usually somewhere between 33 and 37 ppt, which means that a 1-liter bottle of seawater would have 33-37 grams of salt inside
The pointy finger saga continues
Just a thought - what if the photo in the lower right was updated with a current "Doctor Rachel" photo?
That's a wonderful idea, thank you!
Manganese and magnesium sound so similar
Super video. Subscribers +1.
Thank you! ;D
2:07 sorry but can you tell me of these early scientists attempts to date the earth like this?.
Absolutely! I actually have a whole video about that! :D -> ruclips.net/video/suUX9-JAwNM/видео.htmlsi=7YRKPXxPQdvr_Yl0
Nodule Formation?
Soft rocks (like Shale, clay, etc.) interbedded. A tectonic plays compression due to which nodules formed.
What is off camera that is so fascinating?
Loved the video, I do wish they would stop putting the global warming propaganda link on this channel, it makes no sense.
I always enjoy your content, Rachel, thank you.
However, I wonder why your references are only books, instead of supplemented by research papers 🗞️ as well?
I think that complementing textbook references with research would provide more depth, novelty, and perspective to your content.
I have paper refs as well, but haven't put them in the description yet, sorry! I will add them soon! ;)