Exactly. It's not discernible. Hence it's not a catastrophe. You think 1.5C over 174 years is significant. I say it's normal. You say 1.5C is due entirely to 120 ppm of incremental CO2. I say that only 0.22C to 0.5C is due to an incremental 120 ppm of CO2 with the rest being do to natural warming from ocean currents.
Record Cold In Australia
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You are really good at playing dumb.
How lucky for you it comes so naturally.
This is your level of discourse cause it sure ain't ocean engineering.
Who ever said it was? The point of our discussion is that I believe your ideas as to the cause of the glacial-interglacial cycle and the current warming are complete nonsense. I'm not sure what you think about the fact that the opinion I put out here on both those topics is the conclusion of the vast, vast majority of active, published research scientists - you've criticized them on a few occasions - but aside from "its political", you've never explained why you think the world's scientists would all be wrong when you - with whatever qualification you actually have - are not. You have made many, very fundamental errors in fluid dynamics, thermodynamics, oceanography and numerous bits and pieces of really, really basic science. So, you tell me what you think this discourse is all about.
https://www.sciencedirect.com/science/article/abs/pii/S0031018285800201
Deep Atlantic Circulation During the Last Glacial Maximum and Deglaciation
https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/PA005i004p00469
Collapse and rapid resumption of Atlantic meridional circulation linked to deglacial climate changes - Nature
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2010PA002032
None of those provide ANY support for your idea that changes in ocean circulation were responsible for the glacial-interglacial cycle or the current greenhouse warming. None. If you disagree, let's see some excerpts, because I'm tired of wasting my time reading your irrelevant links.https://www.sciencedirect.com/science/article/abs/pii/S0031018285800201
Deep Atlantic Circulation During the Last Glacial Maximum and Deglaciation
https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/PA005i004p00469
Collapse and rapid resumption of Atlantic meridional circulation linked to deglacial climate changes - Nature
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2010PA002032
Depending on the circulation pattern ocean currents can cause the planet to warm or cool in abrupt fashion.
In other words, changing ocean currents are responsible for warming trends and cooling trends up to and including triggering glacial and interglacial periods.
Climate fluctuations and environmental uncertainty increased after the ice age (bipolar glaciation) began 3 million years ago and it is due to the planet's unique landmass distribution and changing ocean currents which is driven by uneven heating of the oceans.
That's what these scientific papers say.
https://www.sciencedirect.com/science/article/abs/pii/S0031018285800201
Deep Atlantic Circulation During the Last Glacial Maximum and Deglaciation
https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/PA005i004p00469
Collapse and rapid resumption of Atlantic meridional circulation linked to deglacial climate changes - Nature
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2010PA002032
Show us an actual quote from a published study that states what you've just stated. That's what I just asked you for but, once again, you just give us links to articles that do NOT support your claims. Prove my ass wrong.
So you don't believe that changing ocean currents can cause warming and cooling trends? You don't believe that changing ocean currents can cause abrupt warming and abrupt cooling?
Really? Is that your position?
My position is that I have YET to see you post a single word from a published, peer-reviewed study that offers that slightest glimmer of support for your contentions. You've put up links, but not one of those I've read supports your claims and when I ask for quotes of text from those linked studies specifically doing so, you whine. You present nothing. Three guess as to what conclusion that leads me.
Then you haven't read these papers very closely.
https://www.sciencedirect.com/science/article/abs/pii/S0031018285800201
Deep Atlantic Circulation During the Last Glacial Maximum and Deglaciation
https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/PA005i004p00469
Collapse and rapid resumption of Atlantic meridional circulation linked to deglacial climate changes - Nature
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2010PA002032
Depending on the circulation pattern ocean currents can cause the planet to warm or cool in abrupt fashion.
In other words, changing ocean currents are responsible for warming trends and cooling trends up to and including triggering glacial and interglacial periods.
Climate fluctuations and environmental uncertainty increased after the ice age (bipolar glaciation) began 3 million years ago and it is due to the planet's unique landmass distribution and changing ocean currents which is driven by uneven heating of the oceans.
That's what these scientific papers say.
Show us some quotes or I will.
Here are things they say:
At times in the past, rapid melting of ice sheets surrounding the North Atlantic was great enough to alter surface salinities, likely reducing the density of deep water formed, and slowing the export of deep water from the North Atlantic. Broecker et al. (1990b) hypothesized that natural oscillations in the rate of water vapor exchange between the Atlantic and the Pacific during the last glacial period were responsible for the rapid, short term fluctuation ocean circulation linked to the abrupt millennial-scale Dansgaard-Oeschger Events seen in the Greenland ice cores
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).
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.
The melting of the vast continental ice sheets, which began ~20,000 years ago due to gradual changes in the seasonal and spatial distribution of the Sun's energy (Broecker & Von Donk 1970), was interrupted by several abrupt cold climate events. The two largest deglacial events in the North Atlantic — known as Heinrich Stadial 1 and the Younger Dryas — occurred approximately 17,500–14,600 and 13,000–11,500 years ago respectively (Figure 6) (Heinrich 1988, Bond et al. 1992, Grootes et al. 1993).
Evidence from marine sediment cores suggests large changes in deep ocean circulation associated with these events.
What these and many more tell us is that ocean currents were altered by changes in the Earth's climate, not vice versa.
Please do. I'd love to see what you think these papers are showing.
You've probably still got time to delete this.
No, what these quotes are showing is how the ocean changed the climates. You just left out the quotes which explained it.
Why would I want to do that? You already know the ocean controls the planet's climate. It's only your political allegiance which prevents you from speaking the truth.
The role of the ocean in storing, distributing and establishing climate is well known and well understood. Change the currents and you change the climate. Some regions are more sensitive to change than others and have more of a global impact than others. The Arctic is that region. The Little Ice age was triggered by a disruption of the ocean's heat circulation to the Arctic and that when that heat circulation was restored, the planet returned to it's natural interglacial warming trend. The contribution of the Industrial Revolution isn't nothing but all warming is not due to it. 0.22C top 0.5C is the contribution of 120 ppm of CO2.
The following are excerpts from papers explaining the science behind the climate changes of the past 3 million years.
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.
https://www.sciencedirect.com/science/article/abs/pii/S0031018285800201
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).
As shown by the work of Dansgaard and his colleagues, climate oscillations of one or so millennia duration punctuate much of glacial section of the Greenland ice cores. These oscillations are characterized by 5°C air temperature changes, severalfold dust content changes and 50 ppm CO2 changes. Both the temperature and CO2 change are best explained by changes in the mode of operation of the ocean. In this paper we provide evidence which suggests that oscillations in surface water conditions of similar duration are present in the record from a deep sea core at 50°N. Based on this finding, we suggest that the Greenland climate changes are driven by oscillations in the salinity of the Atlantic Ocean which modulate the strength of the Atlantic's conveyor circulation.
https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/PA005i004p00469
Warren (1983) first noted that the difference in salinity between the North Pacific and the North Atlantic (Figure 1) was the principal reason deep water formation occurs today only in the North Atlantic. Salty water, when cooled, achieves a higher density and is thus able to sink to greater depth in the water column. Wintertime cooling occurs in both the North Atlantic and North Pacific, but since the surface waters of the North Atlantic are much closer in salinity to the mean of the ocean's deep water, they achieve a density high enough to sink to great water depths. Warren (1983) noted that the salinity of the North Pacific was low because of relatively low evaporation, little exchange with salty tropical waters, and an influx of fresh water from precipitation and river runoff. Emile-Geay et al.(2003) reevaluated the Warren (1983) results and fundamentally confirmed his thesis, noting that atmospheric moisture transport from the Asian monsoon was also an important source of fresh water to the North Pacific not originally considered by Warren. Interestingly, Warren also noted that the North Atlantic had much greater river runoff than the North Pacific, so its higher surface salinities must be the result of greater evaporation in the Atlantic basin.
Broecker et al. (1990a) noted that higher Atlantic salinities are the result of a net transfer of water vapor from the Atlantic to the Pacific over the Isthmus of Panama, equivalent to approximately 0.35 Sverdrup (106 m3 per second). In the absence of other processes, this would raise the salinity of the Atlantic by about 1 salinity unit each 1000 years. If the Atlantic salinity is in balance, then it must be exporting the excess salt (enough to compensate for the lost fresh water) through ocean circulation processes. Today this is occurring through the production and export of North Atlantic Deep Water.
At times in the past, rapid melting of ice sheets surrounding the North Atlantic was great enough to alter surface salinities, likely reducing the density of deep water formed, and slowing the export of deep water from the North Atlantic. Broecker et al. (1990b) hypothesized that natural oscillations in the rate of water vapor exchange between the Atlantic and the Pacific during the last glacial period were responsible for the rapid, short term fluctuation ocean circulation linked to the abrupt millennial-scale Dansgaard-Oeschger Events seen in the Greenland ice cores (Figure 9).
- The ocean stores the majority of heat the earth receives from the sun
- The ocean holds 1000 times more heat than the atmosphere
- The ocean distributes that heat to the rest of the globe using currents
- Without ocean currents the polar regions would be colder and the equator would be hotter such that much of the planet would be inhospitable for life
- Ocean currents are affected by density (salinity and thermal expansion) and wind.
- Wind patterns are affected by the sun
- If heat circulation from the Atlantic to the Arctic were disrupted it would lead to catastrophic cooling
The following are excerpts from papers explaining the science behind the climate changes of the past 3 million years.
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.
https://www.sciencedirect.com/science/article/abs/pii/S0031018285800201
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
As shown by the work of Dansgaard and his colleagues, climate oscillations of one or so millennia duration punctuate much of glacial section of the Greenland ice cores. These oscillations are characterized by 5°C air temperature changes, severalfold dust content changes and 50 ppm CO2 changes. Both the temperature and CO2 change are best explained by changes in the mode of operation of the ocean. In this paper we provide evidence which suggests that oscillations in surface water conditions of similar duration are present in the record from a deep sea core at 50°N. Based on this finding, we suggest that the Greenland climate changes are driven by oscillations in the salinity of the Atlantic Ocean which modulate the strength of the Atlantic's conveyor circulation.
https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/PA005i004p00469
Water Masses in the Deep Atlantic Ocean
The Atlantic Ocean is the only ocean basin that features the transformation of surface-to-deepwater near both poles. Warm salty tropical surface waters flowing northward in the western Atlantic cool in transit to and within the high-latitude North Atlantic, releasing heat to the overlying atmosphere and increasing seawater density. Once dense enough, these waters sink and flow southward between ~ 1000 and 4000m. This North Atlantic Deep Water (NADW), as it is called, flows from the Atlantic to the Southern Ocean where much of it upwells — or rises to the surface — around Antarctica, and some of it circulates Antarctica before entering the rest of the world's deep oceans. Antarctic Bottom Water (AABW), which is formed close to Antarctica, is denser than NADW, and flows northward in the Atlantic below NADW. AABW is confined to water depths below 4000 meters in the tropical and North Atlantic. Antarctic Intermediate Water (AAIW) flows northward above NADW. The presence of these three water masses in the Atlantic Ocean is evident in cross-sections of many water properties, including salinity, phosphate concentration and carbon isotope ratios (Figure 2). The residence time of deepwater in the western Atlantic is approximately 100 years (Broecker 1979), meaning that the average water parcel spends about a century in the deep Atlantic.Why is Deep Water Formed in the Atlantic and not the Pacific?
Warren (1983) first noted that the difference in salinity between the North Pacific and the North Atlantic (Figure 1) was the principal reason deep water formation occurs today only in the North Atlantic. Salty water, when cooled, achieves a higher density and is thus able to sink to greater depth in the water column. Wintertime cooling occurs in both the North Atlantic and North Pacific, but since the surface waters of the North Atlantic are much closer in salinity to the mean of the ocean's deep water, they achieve a density high enough to sink to great water depths. Warren (1983) noted that the salinity of the North Pacific was low because of relatively low evaporation, little exchange with salty tropical waters, and an influx of fresh water from precipitation and river runoff. Emile-Geay et al.(2003) reevaluated the Warren (1983) results and fundamentally confirmed his thesis, noting that atmospheric moisture transport from the Asian monsoon was also an important source of fresh water to the North Pacific not originally considered by Warren. Interestingly, Warren also noted that the North Atlantic had much greater river runoff than the North Pacific, so its higher surface salinities must be the result of greater evaporation in the Atlantic basin.
Broecker et al. (1990a) noted that higher Atlantic salinities are the result of a net transfer of water vapor from the Atlantic to the Pacific over the Isthmus of Panama, equivalent to approximately 0.35 Sverdrup (106 m3 per second). In the absence of other processes, this would raise the salinity of the Atlantic by about 1 salinity unit each 1000 years. If the Atlantic salinity is in balance, then it must be exporting the excess salt (enough to compensate for the lost fresh water) through ocean circulation processes. Today this is occurring through the production and export of North Atlantic Deep Water.
At times in the past, rapid melting of ice sheets surrounding the North Atlantic was great enough to alter surface salinities, likely reducing the density of deep water formed, and slowing the export of deep water from the North Atlantic. Broecker et al. (1990b) hypothesized that natural oscillations in the rate of water vapor exchange between the Atlantic and the Pacific during the last glacial period were responsible for the rapid, short term fluctuation ocean circulation linked to the abrupt millennial-scale Dansgaard-Oeschger Events seen in the Greenland ice cores (Figure 9).
Deep Atlantic Circulation During the Last Glacial Maximum and Deglaciation
What Replaces the Deep Water that Leaves the Atlantic?
There are three main pathways for water to return to the North Atlantic and renew NADW, a warm-water route and two cold water routes (Figure 3). The "warm-water route" begins with the flow of surface and thermocline water from the Pacific to the Indian Ocean through the Indonesian Seas. Both colder return flows involve Antarctic Intermediate Water (AAIW), described above. AAIW enters the southern South Atlantic through the Drake Passage between Antarctica and South America, with some flowing into the Atlantic and some flowing into the Indian Ocean. AAIW also enters the Indian Ocean from south of Tasmania and flows westward towards Africa, where it joins the warm-water flow and the other branch of AAIW before rounding southern Africa, entering the South Atlantic, and flowing northward (Gordon 1985, Speich et al. 2002). Along its transit to the North Atlantic, AAIW from the Drake Passage, flowing above Tasman AAIW, mixes with overlying water and contributes to the "warm-water route" (Gordon 1986). These return flows provide a significant source of heat to high northern latitudes. Together, southward flow of water in the deep Atlantic and its shallower return flows are a large component of what is known as the global Meridional Overturning Circulation (MOC).Deep Atlantic Circulation During the Last Glacial Maximum and Deglaciation
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