It is found that the global salinity variations associated with the thermohaline circulation may have a tendency to make the circulation increasingly asymmetric with respect to the equator. As a consequence the salinity difference between the Pacific and the Atlantic Ocean may be slowly increasing. Such a process could have a time scale long enough to be comparable with the time span between major glaciations. A speculative glaciation cycle is proposed which involves the above mentioned property of the thermohaline circulation. In this cycle the role of a Northern Hemisphere glaciation is to bring excess freshwater from the Pacific to the Atlantic.
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Atlantic Ocean Circulation During the Last Ice Age
There is strong evidence that the circulation of the deep Atlantic during the peak of the last Ice Age, or the Last Glacial Maximum (LGM; ~22,000 to 19,000 years ago) was different from the modern circulation (Boyle & Keigwin 1987, Duplessy et al. 1988, Marchal & Curry 2008). Compilations of deepwater δ13C and CdW for the LGM (Figure 5) show several features that contrast with their modern distributions. Whereas much of the modern deep western Atlantic has similar δ13C values because it is filled with NADW, during the LGM, the range of δ13C values was larger than today, with higher values in NADW and lower values in AABW. The main core of high-δ13C, low-CdW NADW was at least 1000 meters shallower than today, probably because the density difference between surface waters and deep water was reduced — surface salinity may have decreased as a result of less evaporation due to colder glacial temperatures, and as a result of input of freshwater from glaciers surrounding the North Atlantic (Boyle & Keigwin 1987). In the western Atlantic, depths below ~2 km were filled with AABW. Radiocarbon data suggest that deepwater was older (Keigwin & Schlegel 2002), consistent with less NADW and more AABW as indicated by the δ13C and CdW of benthic foraminifera. Glacial δ13C data from the eastern Atlantic suggest that the boundary between glacial AABW and glacial NADW may have been shallower than in the western Atlantic (Sarnthein et al. 1994), although the difference may be the result of local effects caused by increased glacial productivity and higher rates of remineralization of low-δ13C organic carbon in the eastern basin. Inferences using other kinds of proxy data of deep Atlantic circulation are consistent with the changes inferred from δ13C, Cd/Ca and 14C of benthic foraminifera (Lynch-Steiglitz et al. 2007).
Deep Atlantic Circulation During the Last Glacial Maximum and Deglaciation
How has deep ocean circulation changed in the past, and how have the changes affected Earth's climate? Reconstructing ocean circulation and climate history using geological records.
www.nature.com
No offense but your reply was so dumb that it doesn't really merit a response. It's not about salt transport and maybe read up on the factors which contribute to ocean currents and where the majority of the heat is stored. I'll leave it at that.
This article is from 1985. The idea doesn't seem to have taken off.
And you claim to have an ocean engineering degree.
ReinyDays
Platinum Member
Water flow rate has nothing to do with water flow rate ... well done, my friend, well done ...
Surface currents are around 300 million m^3/s of water ... the thermohaline currents closer to 15 million m^3/s of water ...
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And your point is?
I don't just claim, I do.
If mainstream science - or any science at all - agreed with you that changes in ocean heat transport were responsible for global warming, then it would have been mentioned here. But it is NOT.
Really? What job did you have where you used it? Because you seem quite ignorant about how the ocean drives the climate of the planet. In fact, you seem to be disputing that the ocean drives the climate of the planet.
Then mainstream science - which has become corrupted by politics - is wrong.
There is a much more obvious solution: you're contentions concerning what drives glacial cycles and what is the cause of the current warming are all completely incorrect.
Orbital cycles have no mechanism for triggering or ending a glacial period. None, nada, zip, zilch.
There is ample evidence from the geologic record that says heat circulation from the ocean does. Tons.
All the world's scientists disagree. You need to figure out why.
Not one scientist has explained the mechanism for orbital forcing to trigger glacial periods and trigger the end of glacial periods. Feel free to explain how orbital forces have caused glacial cycles.
That last time you tried that (the day before yesterday I think) I put up the first five articles from a Google search on the topic ALL stating that glacial cycles were driven my Milankovitch orbital forcing. You didn't forget that. You're simply lying now.
What's the mechanism? Can't you state it? Because I never saw stated in any of your links. So if it's really in those links, then explain how it works. How much do these orbital cycles lower and raise earth's surface temperatures and how does it do it?
Open Google and put this in: "How do Milankovitch cycles affect the climate?" If you find that difficult, you could tack on "...explained for the scientifically illiterate". But this is what you should see:
Milankovitch (Orbital) Cycles and Their Role in Earth's ...
NASA Science (.gov)
https://science.nasa.gov › science-research › earth-science
Feb 27, 2020 — The small changes set in motion by Milankovitch cycles operate separately and together to influence Earth's climate over very long timespans, ...
Why Milankovitch (Orbital) Cycles Can't Explain Earth's ...
NASA Science (.gov)
https://science.nasa.gov › science-research › earth-science
Mar 18, 2024 — Second, Milankovitch cycles are just one factor that may contribute to climate change, both past and present. Even for Ice Age cycles, changes ...
Milankovitch cycles: What are they and how do they affect ...
Space.com
https://www.space.com › ... › Solar System › Earth
Jun 14, 2022 — Scientists think that Milankovitch cycles cause periodic changes in Earth's climate. Periodic changes in Earth's orbital parameters called the ...
‎What drives the Milankovitch... · ‎Do Milankovitch cycles have...
How do the Milankovitch cycles affect climate change?
Socratic
https://socratic.org › ... › Models of the Solar System
I think it is true that Milankovitch cycles have some impact on climate, but it is dwarfed (currently) by human induced climate change due to CO2 , methane and ...
2 answers · They clearly have little impact, or climatologists would have seen a repetitive 26 000 year ...
Milankovitch Cycles, Paleoclimatic Change, and Hominin ...
Nature
https://www.nature.com › scitable › knowledge › library
Milankovitch: Milutin Milankovitch (1879–1958), a Serbian mathematician who proposed that climatic changes, particularly ice ages, were the result of variations ...
Milankovitch Cycles and Climate Change
climatedata.info
http://www.climatedata.info › forcing › milankovitch-c...
Milankovitch cycles describe the changes in the way the earth orbits the sun. These changes define the sequence of ice ages and warm periods.
Milankovitch cycles
Wikipedia
https://en.wikipedia.org › wiki › Milankovitch_cycles
Milankovitch cycles describe the collective effects of changes in the Earth's movements on its climate over thousands of years. The term was coined and ...
Milankovitch Cycles - Climate Change & Nature: New Zealand
climateandnature.org.nz
https://climateandnature.org.nz › climate-wiki › causes
Video 1: The Milankovitch Cycles are changes in the Earth's orbit and rotation that cause the Earth's climate to change over hundreds of thousands of years.
Milankovitch-cycles-Wikipedia.pdf
Harvard University
https://courses.seas.harvard.edu › eli › Glacial-cycles
This article shows the influence of Milankovitch cyles on climate variation during the late. Oligocene and early Miocene, around 20-25 million years ago.
9 pages
So, when you suggested that no one was explaining the mechanism, you were simply lying. Again.
How? How do they do it? You can't explain it because no one knows or has explained it because there is no mechanism that can explain it because it has nothing to do with triggering glacial cycles unless it is due to changing wind patterns which disrupt heat circulation from the Atlantic to the Arctic which is an obvious and well understood mechanism for not only triggering glacial periods but ending glacial periods as well.
So walk me through it or shut up about them.
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I have gone well above and beyond what USMB and common courtesy require of me to explain to you how they work.
Another Ding mistake.
Actually you haven't. You can't explain the mechanics. Because none exist. There are no known mechanics.
But there are for AMOC switch off.
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