Orbital Variations Effects on Interglacial Behavior and Paleohydrological Events during the Quaternary Ice Age: A Compilation of MOTM editorial pieces
January 14, 2019
January 14, 2019
We are currently in an inter-glacial period that started about 11,500 years ago. Our current inter-glacial period is part of the Pleistocene that started 2.5 million years ago. This time period was marked by advancing and retreating of ice glaciers that were close 1,500 and 3,000 meters thick. At the full extent the glaciers average temperature along the edge of the ice was 21 degrees Fahrenheit and the ice covered close to 30% of all the land mass in the world as compared to 10% right now. These climatic changes often led to a 300 ft drop in the sea level compared to current sea level.
However, it has been observed that about every 40,000-100,000 years ago the glaciers would retreat. Modern science has discovered that orbital variation known as the Milankovitch cycle have been causing these milder events known as interstadials. Climate change driven by Orbital variation may not be limited to the Ice Age. It has been observed that orbital variation may have been a very important driver for climate change for 1.4 billion years .
"We report geochemical and sedimentological evidence for repeated, short-term climate fluctuations from the exceptionally well-preserved ∼1.4-billion-year-old Xiamaling Formation of the North China Craton. We observe two patterns of climate fluctuations: On long time scales, over what amounts to tens of millions of years, sediments of the Xiamaling Formation record changes in geochemistry consistent with long-term changes in the location of the Xiamaling relative to the position of the Intertropical Convergence Zone."
"We report geochemical and sedimentological evidence for repeated, short-term climate fluctuations from the exceptionally well-preserved ∼1.4-billion-year-old Xiamaling Formation of the North China Craton. We observe two patterns of climate fluctuations: On long time scales, over what amounts to tens of millions of years, sediments of the Xiamaling Formation record changes in geochemistry consistent with long-term changes in the location of the Xiamaling relative to the position of the Intertropical Convergence Zone."
A recent example of an interstadial that has been well documented is an inter-glacial event that happened roughly 115,000 to 130,000 years ago known as the Eemian. During the Eemian the global temperature was several degrees Celsius higher than it is today and the oceans were somewhere 20-30 feet deeper. This of course is not even considered an anomaly, it is estimated that all the inter-glacial periods might have had similar climate conditions as the Eemian. There is even evidence that Greenland may have been ice free for 280,000 years about 1.1 million years ago. What is even more remarkable is that many ice age mega fauna that went extinct 11,000 years ago survived the previous interstadials even though the oceans were higher and the temperatures were warmer; forests reached North Cape, Norway.
Moving into the realm of humankind’s recorded history, many scientists in the world believe that carbon dioxide is currently the main contributor to a recently modest increase in temperature. The word modest is used loosely in the sense that there are many who believe that large climatic changes are happening as seen through the eyes of modern human beings and through recorded history. If you discount warming periods observed by Romans and Vikings.
Current climate conditions compared to climate changes over hundreds of millions of years, nothing probably seems out of the ordinary. And current shrinking glaciers do not even compare to the disappearance of ice that covered a large extent of North America and Eurasia. Matter of fact, current climatic trends might be so shocking to people because we have no personal experience to relate to the massive changes on earth that occurred only 10,000 years ago. It is believed that Tagalog sea level rose by a total of more than 120 meters as the vast ice sheets receded. This melt-back lasted from about 19,000 to about 6,000 years ago, meaning that the average rate of sea-level rise was roughly 1 (39.4 inches) meter per century. It also believe that during some periods the ocean may have risen close to 5 (196.85 inches) meters a century. This rate was an order of magnitude larger then the estimated 4-8 inch rise observed during the twentieth century. To give you an idea of how much faster the oceans were rising 10,000 years ago compared to the twentieth century; 450% to 900% meter/century rate faster using the average estimated rate and 2,250% to 4,500% meter/century using the accelerated rate. However, there is no doubt that carbon dioxide concentrations are increasing across the board. And many studies show that ocean temperatures are increasing faster then the surface temperature and temperature magnification at the poles. However, lets compare this to data from the past and present.
We do see a small modest increase in the average global temperature. However, as a rough estimate, the last glacial advance was 9-12 degrees Fahrenheit cooler than the temperatures of the 20th Century. That means that the temperature increased 20-28% before human beings started to record and measure temperatures. It also has to be taken into account most of that temperature change happened in a very short period of time over 11,000 years ago. This compared to a 2-3% temperature increase in the last century . This does not even take into account that over half of the current temperature increase might be natural, back ground noise, or hyper sensitivity from technological advances in temperature detection.
Plus, during the Emmian period Earth saw temperatures higher then our current global averages. And it has been observed that temperatures in the Antarctica were higher in the last two inter-glacial periods then the current temperatures. What they are also finding is that the global temperatures spiked and went up towards the end of several inter-glacial periods. This suggest that an increase in temperature might be normal, including an additional sea level rise of another 20-30 feet. This might be a common occurrence that drives the earth into a glacial period. A research paper from 2009 showed Antarctica in a previous inter glacial may have been 6 degrees Celsius higher then today. In a recent lecture by Ayako Abe-Ouchi, Atmosphere and Ocean Research Institute at The University of Tokyo, lectures on Modeling the 100,000-year Glacial-interglacial Cycles, says, "carbon dioxide is a very important amplifier, but not a driver."
And some accuracy in predicting climate change can be lost in background noise and variation caused by forest, aerosols, sun spots, and natural occurrence. A recent statement about deforestation reads as the following.
"When the impacts on biogenic SOA, O3 and CH4 are combined, global deforestation exerts an overall positive RF of between +81.1 and +135.9 mW m−2 through changes to short-lived climate forcers (SLCF). Taking these additional biogeochemical impacts into account increases the net positive RF of complete global deforestation, due to changes in CO2 and surface albedo, by 7-11%. Overall, our work suggests that deforestation has a stronger warming impact on climate than previously thought."
"When the impacts on biogenic SOA, O3 and CH4 are combined, global deforestation exerts an overall positive RF of between +81.1 and +135.9 mW m−2 through changes to short-lived climate forcers (SLCF). Taking these additional biogeochemical impacts into account increases the net positive RF of complete global deforestation, due to changes in CO2 and surface albedo, by 7-11%. Overall, our work suggests that deforestation has a stronger warming impact on climate than previously thought."
Other variations in climate could be Chaotic Solar system, sun spots, climate inertia, and ultra-hypersensitive collection of new data by new technological means that did not exist 50 years ago. Recently CLOUD said that aerosols may be underestimated in modeling attempts for climate change and suggest that the scientific community reduces it's "climate sensitivity." There statement below reads as the following.
"Early this year, CLOUD reported in Nature the discovery that aerosol particles can form in the atmosphere purely from organic vapors produced naturally by the biosphere (CERN Courier July/August 2016 p11). In a separate modelling paper published recently in PNAS, CLOUD shows that such pure biogenic nucleation was the dominant source of particles in the pristine pre-industrial atmosphere. By raising the baseline aerosol state, this process significantly reduces the estimated aerosol radiative forcing from anthropogenic activities and, in turn, reduces modelled climate sensitivities.
“This is a huge step for atmospheric science,” says lead-author Ken Carslaw of the University of Leeds, UK. “It’s vital that we build climate models on experimental measurements and sound understanding, otherwise we cannot rely on them to predict the future. Eventually, when these processes get implemented in climate models, we will have much more confidence in aerosol effects on climate. Already, results from CLOUD suggest that estimates of high climate sensitivity may have to be revised downwards.”
Recently, a scientist named Dr. John Bates has been the topic of many viral stories, alleging that he is a whistle blower of sorts exposing falsified data on climate change. Though much of these stories were not entirely true,. what his recent blog illustrates is that climate change might be science, but it is not black and white and many people argue and differ in opinion on everything. People forget how messy science can be, and sometimes the right answer is the least wrong until a better theory replaces it. You can read his blog here (Climate scientists versus climate data)
"The most serious example of a climate scientist not archiving or documenting a critical climate dataset was the study of Tom Karl et al. 2015 (hereafter referred to as the Karl study or K15), purporting to show no ‘hiatus’ in global warming in the 2000s (Federal scientists say there never was any global warming “pause”). The study drew criticism from other climate scientists, who disagreed with K15’s conclusion about the ‘hiatus.’ (Making sense of the early-2000s warming slowdown). The paper also drew the attention of the Chairman of the House Science Committee, Representative Lamar Smith, who questioned the timing of the report, which was issued just prior to the Obama Administration’s Clean Power Plan submission to the Paris Climate Conference in 2015.
"Early this year, CLOUD reported in Nature the discovery that aerosol particles can form in the atmosphere purely from organic vapors produced naturally by the biosphere (CERN Courier July/August 2016 p11). In a separate modelling paper published recently in PNAS, CLOUD shows that such pure biogenic nucleation was the dominant source of particles in the pristine pre-industrial atmosphere. By raising the baseline aerosol state, this process significantly reduces the estimated aerosol radiative forcing from anthropogenic activities and, in turn, reduces modelled climate sensitivities.
“This is a huge step for atmospheric science,” says lead-author Ken Carslaw of the University of Leeds, UK. “It’s vital that we build climate models on experimental measurements and sound understanding, otherwise we cannot rely on them to predict the future. Eventually, when these processes get implemented in climate models, we will have much more confidence in aerosol effects on climate. Already, results from CLOUD suggest that estimates of high climate sensitivity may have to be revised downwards.”
Recently, a scientist named Dr. John Bates has been the topic of many viral stories, alleging that he is a whistle blower of sorts exposing falsified data on climate change. Though much of these stories were not entirely true,. what his recent blog illustrates is that climate change might be science, but it is not black and white and many people argue and differ in opinion on everything. People forget how messy science can be, and sometimes the right answer is the least wrong until a better theory replaces it. You can read his blog here (Climate scientists versus climate data)
"The most serious example of a climate scientist not archiving or documenting a critical climate dataset was the study of Tom Karl et al. 2015 (hereafter referred to as the Karl study or K15), purporting to show no ‘hiatus’ in global warming in the 2000s (Federal scientists say there never was any global warming “pause”). The study drew criticism from other climate scientists, who disagreed with K15’s conclusion about the ‘hiatus.’ (Making sense of the early-2000s warming slowdown). The paper also drew the attention of the Chairman of the House Science Committee, Representative Lamar Smith, who questioned the timing of the report, which was issued just prior to the Obama Administration’s Clean Power Plan submission to the Paris Climate Conference in 2015.
In the following sections, I provide the details of how Mr. Karl failed to disclose critical information to NOAA, Science Magazine, and Chairman Smith regarding the datasets used in K15. I have extensive documentation that provides independent verification of the story below. I also provide my suggestions for how we might keep such a flagrant manipulation of scientific integrity guidelines and scientific publication standards from happening in the future. Finally, I provide some links to examples of what well documented CDRs look like that readers might contrast and compare with what Mr. Karl has provided."
One thing is for sure; our future civilization will face global sea rises or another glaciation period. And it is possible they may face both. But if current climate conditions were compared to the past, earth is relatively stable, all considering snowball, asteroids, volcanic activity, continental shifts, carbon dioxide concentrations, and more. Also, current temperatures are relatively low compared to temperatures that occurred over Earth the last 500 million years. So, maybe rising temperatures is more normal then we think? Most people reading this are more likely to see major global calamities caused by war, famine, pestilence, economic upheaval, humanitarian crisis; which is usually caused by over population, micro cyclic weather patterns, economic stagnation, and various forms of human conflict. But you never know, a small foot rise in the ocean might be the thing that pushes our modern civilization over the precipice. But all this means is that there is a lot more to learn about our Climate.
One thing is for sure; our future civilization will face global sea rises or another glaciation period. And it is possible they may face both. But if current climate conditions were compared to the past, earth is relatively stable, all considering snowball, asteroids, volcanic activity, continental shifts, carbon dioxide concentrations, and more. Also, current temperatures are relatively low compared to temperatures that occurred over Earth the last 500 million years. So, maybe rising temperatures is more normal then we think? Most people reading this are more likely to see major global calamities caused by war, famine, pestilence, economic upheaval, humanitarian crisis; which is usually caused by over population, micro cyclic weather patterns, economic stagnation, and various forms of human conflict. But you never know, a small foot rise in the ocean might be the thing that pushes our modern civilization over the precipice. But all this means is that there is a lot more to learn about our Climate.
Since 1880 the ocean began to rise briskly, climbing a total of 210 mm (8.3 in) through 2009- about 7 inches a century. However, if you put that in a historical perspective; 19,000 to 6,000 years ago the sea level raise rate was roughly 529% to 2814% higher then today. Oceans during this time raised close to 120 metres (4,724 inches), this would be 56,915% percent larger then the 8.3 inch sea level raise since 1880. This all happened from 18,000 to 4,000 years before the birth of Jesus.
National Oceanography Centre
"Global sea level rose by a total of more than 120 metres as the vast ice sheets of the last Ice Age melted back. This melt-back lasted from about 19,000 to about 6,000 years ago, meaning that the average rate of sea-level rise was roughly 1 metre (37 inches) per century. Previous studies of sea-level change at individual locations have suggested that the gradual rise may have been marked by abrupt ‘jumps’ of sea-level rise at rates that approached 5 (197 inches) metres per century. Their analyses indicate that the gradual rise at an average rate of 1 metre per century was interrupted by two periods with rates of rise up to 2.5 metres (98 inches) per century, between 15 and 13 thousand years ago, and between 11 and 9 thousand years ago."
However, this is not the whole story. Recent data pulled from the NASA website suggests that the sea level fluctuated very little since September 16, 2015. In other words, no observable data in the last 2 years can show a discernible sea level rise at all.
"Global sea level rose by a total of more than 120 metres as the vast ice sheets of the last Ice Age melted back. This melt-back lasted from about 19,000 to about 6,000 years ago, meaning that the average rate of sea-level rise was roughly 1 metre (37 inches) per century. Previous studies of sea-level change at individual locations have suggested that the gradual rise may have been marked by abrupt ‘jumps’ of sea-level rise at rates that approached 5 (197 inches) metres per century. Their analyses indicate that the gradual rise at an average rate of 1 metre per century was interrupted by two periods with rates of rise up to 2.5 metres (98 inches) per century, between 15 and 13 thousand years ago, and between 11 and 9 thousand years ago."
However, this is not the whole story. Recent data pulled from the NASA website suggests that the sea level fluctuated very little since September 16, 2015. In other words, no observable data in the last 2 years can show a discernible sea level rise at all.
Nor is the current shrinking of Greenland's Glaciers Unique. D Dahl-Jensen 2013showed that Greenland's glaciers 122,000 years ago, during the Eemian, reached surface elevations 130 ± 300 metres lower than today. Is the Arctic Ocean's shrinking summer ice concentrations unique?
One of the arguments that exists why the Eemian is not a good analogy for what is happening right now is that the Arctic sea still had summer ice coverage as compared to current conditions. The argument also suggests that the current conditions are unique because the Arctic ocean was cooling during the late Eemian. Recent observations by Stein en al 2017 show that there is discrepancies in these widely held opinions. Their data showed that the Arctic Ocean may have been close to ice free from 116,000 to 120,000 years ago.
"There, planktic δ18O records from cores MD95-2010 and MD99-2304 (for core locations see Fig. 7e) document a climatic optimum in the early-middle part of the LIG between about 126 and 116 ka, related to a strong poleward extension of warm Atlantic Water. These conditions are quite similar to those also described for the Early Holocene at cores MSM5/5-712-2 and NP05-11-70GC (Fig; see Fig. 7e for core locations), i.e., very low PIP25 values of 0.2 and less, interpreted as almost ice-free conditions triggered by increased Atlantic Water inflow."
One of the arguments that exists why the Eemian is not a good analogy for what is happening right now is that the Arctic sea still had summer ice coverage as compared to current conditions. The argument also suggests that the current conditions are unique because the Arctic ocean was cooling during the late Eemian. Recent observations by Stein en al 2017 show that there is discrepancies in these widely held opinions. Their data showed that the Arctic Ocean may have been close to ice free from 116,000 to 120,000 years ago.
"There, planktic δ18O records from cores MD95-2010 and MD99-2304 (for core locations see Fig. 7e) document a climatic optimum in the early-middle part of the LIG between about 126 and 116 ka, related to a strong poleward extension of warm Atlantic Water. These conditions are quite similar to those also described for the Early Holocene at cores MSM5/5-712-2 and NP05-11-70GC (Fig; see Fig. 7e for core locations), i.e., very low PIP25 values of 0.2 and less, interpreted as almost ice-free conditions triggered by increased Atlantic Water inflow."
Also, during the Eemian, "the mean air temperatures in Northeast Siberia that were about 9 °C higher than today air temperatures above the Greenland NEEM ice core site of about 8 ± 4 °C above the mean of the past millennium North Atlantic sea-surface temperatures of about 2 °C higher than the modern (PI) temperatures and a global sea level 5–9 m above the present sea level (Stein en al 2017)". Further more an addition paper from Stein el al 2017 shows that there was a significant increase in ice in the Chukchi Sea and the East Siberian Sea the last 4,500 years as compared to the early Holocene. These new findings are excellent science work and engaging to the reader. The reader will be left with many mysteries and the papers themselves only open doors to more questions and provide a direction for research to head in.
We would also like to state we are not suggesting that Carbon Dioxide levels are not rising or ocean and surface temperatures have trended up lately. It is widely held in the science community that Carbon Dioxide levels are rising and there has been observable temperature increases globally on the surface and in the ocean. We are only suggesting that Climate Sensitivity be dialed down and let these people continue to do their research on the Eemian, Penultimate, and other earlier interglacial undisturbed by global warming hysteria...
Everybody is talking about the oceans rising and the ending of the world. But what would happen if the glaciers blanketed Canada and Eurasia. In a world looking for more certainty this recent research only leads to more questions.
Everybody is talking about the oceans rising and the ending of the world. But what would happen if the glaciers blanketed Canada and Eurasia. In a world looking for more certainty this recent research only leads to more questions.
6,000 to 500 years ago
Since the last interglacial, Eemain 115kya, the earth has experienced several catastrophic paleohydrological events toward the end of Pleistocene 30kya-11kya and the Holocene 11kya to 1500AD driven by the glaciers advancing and retreating and Orbital Variations. In an earlier article by MOTM, it has been pointed out that, “However, if you put that in a historical perspective; 19,000 to 6,000 years ago the sea level raise rate was roughly 529% to 2814% higher than today. Oceans during this time raised close to 120 metres (4,724 inches), this sea level raise would be 56,915% percent larger than the 8.3 inch sea level raise observed 1880. This all happened from 18,000 to 6,000 years.” This article introduces sea level rise from retreating glaciers responding to orbital variations and the conundrum of increased ice near East Siberia in the late Holocene. That is not the end of the story, some have often said that we live in one of the most extreme and fast changing climate periods in earth history. This argument does not give credit and respectful appreciation for all the massive climate change events that happened 30,000 to 500 years ago. The current climate seems rather stable and calm compared to many of the events that happened 18,000 to 500 years ago.
Since the last interglacial, Eemain 115kya, the earth has experienced several catastrophic paleohydrological events toward the end of Pleistocene 30kya-11kya and the Holocene 11kya to 1500AD driven by the glaciers advancing and retreating and Orbital Variations. In an earlier article by MOTM, it has been pointed out that, “However, if you put that in a historical perspective; 19,000 to 6,000 years ago the sea level raise rate was roughly 529% to 2814% higher than today. Oceans during this time raised close to 120 metres (4,724 inches), this sea level raise would be 56,915% percent larger than the 8.3 inch sea level raise observed 1880. This all happened from 18,000 to 6,000 years.” This article introduces sea level rise from retreating glaciers responding to orbital variations and the conundrum of increased ice near East Siberia in the late Holocene. That is not the end of the story, some have often said that we live in one of the most extreme and fast changing climate periods in earth history. This argument does not give credit and respectful appreciation for all the massive climate change events that happened 30,000 to 500 years ago. The current climate seems rather stable and calm compared to many of the events that happened 18,000 to 500 years ago.
Recently, newly discovered evidence from tree rings, from 1300 -1900, showed multi-decade megadroughts in North America Griffin et al 2007. One of these droughts, in 1550, has been speculated that it may have led to the death of more indigenous people in the region that is now called Mexico then even compared to the death toll caused by the introduction of small pox Therrell et al 2002.
This drought increased the frequency of certain epidemics, Cocliztli, that may have led to the death of over 80% of the population of indigenous people living in Mexico Elliot and Hunt 2002. Nor were these megadroughts unique to North America, during the same time Europe was having its own warm period and megadrought. During 1540 Europe saw temperatures that were significantly elevated compared to temperatures recorded from 1966 to 2015 Rene Orth et al 2016. This heat wave was also accompanied by an 11-month-long Megadrought that covered 2 to 3 million km2 Spring et al 2014.
This drought increased the frequency of certain epidemics, Cocliztli, that may have led to the death of over 80% of the population of indigenous people living in Mexico Elliot and Hunt 2002. Nor were these megadroughts unique to North America, during the same time Europe was having its own warm period and megadrought. During 1540 Europe saw temperatures that were significantly elevated compared to temperatures recorded from 1966 to 2015 Rene Orth et al 2016. This heat wave was also accompanied by an 11-month-long Megadrought that covered 2 to 3 million km2 Spring et al 2014.
Furthermore Tree rings analysis from Europe show chaotic weather patterns in Europe over the last 2,500 years that even coincide with the ending of the Western Roman Empire and the great migration phase in Europe during 250-600 CE Esper et al 2011. These climatic ecosystem alternating events are not limited to North America or Europe. 6,000 years ago Sahara Desert was covered in grass and shrubs and supported a savannah like ecosystem covering millions of square miles. Due to a slight change in the orbital variation of earth the Sahara started to dry up and the level of precipitation begin to decline NOAA. Within an abrupt short period; by 5,000 years ago the Sahara Desert was almost completely reduced to an ever growing desert.
Could early climate change be the result of human influence of deforestation and human related grazing? It is speculated by some groups that Sahara Desertification might have been due to heavy grazing 6,000 years ago. However, scientific evidence shows a very strong correlation with weather pattern changes caused by orbital variation of earth. However, it has been widely accepted that over half of Europe’s forests have been removed by human activity within the last 6,000 years. Could this have had a strong enough impact to cause the drought and heat waves of 1540 AD? Many of the current heat waves accompanied by a megadrought have not reached the same level of intensity. However, there is no doubt that Humankind is having some micro or maco level effects on the ecosystems and climate. Are they as extreme as we think?
30,000 to 15,000 years ago
Let’s make a trip back to North America 30,000 to 15,000 years ago. The oceans are close to a 120 meters lower, the majority of Canada is covered by glaciers, and the landscape was significantly cooler. The extinct mega fauna such as the Western Horse, North American Lions, Short faced bears, Columbian Mammoth, Giant bison, American Mastodons (5mya-8.5kya), Jefferson’s ground sloth, Dire Wolves, Camelops (7ft at shoulder, 4mya-11kya), North American Cheetah, Stag-Moose, Saber-tooth cat, Shrub ox, American Mountain Deer, Beautiful Armadillo (1.2m length, 1.8mya-11kya), Pygmy Mammoth (8.5 kya, Channel Islands, CA), Giant Beaver, Woolly Mammoth, and etc dot the landscape. What is really unique about these animals is that many of them existed for several million years before their extinction?
Let’s make a trip back to North America 30,000 to 15,000 years ago. The oceans are close to a 120 meters lower, the majority of Canada is covered by glaciers, and the landscape was significantly cooler. The extinct mega fauna such as the Western Horse, North American Lions, Short faced bears, Columbian Mammoth, Giant bison, American Mastodons (5mya-8.5kya), Jefferson’s ground sloth, Dire Wolves, Camelops (7ft at shoulder, 4mya-11kya), North American Cheetah, Stag-Moose, Saber-tooth cat, Shrub ox, American Mountain Deer, Beautiful Armadillo (1.2m length, 1.8mya-11kya), Pygmy Mammoth (8.5 kya, Channel Islands, CA), Giant Beaver, Woolly Mammoth, and etc dot the landscape. What is really unique about these animals is that many of them existed for several million years before their extinction?
They have crossed the land bridge between continents; they survived over a dozen interglacial periods. The last two interglacials had temperatures even slightly warmer then current temperatures. Even more, during the Eemian the oceans were over 20-30 feet higher then present sea level. This time represented extraordinary natural wildlife living in a world with extraordinary hydrological events that dwarf current events. As you can see in the picture below shows that the full extent of the glaciers in North America was reached about 18,000 years ago. The glaciers then started to retreat North East for the next 12,000 years until 6,000 years ago. Coincidentally, 6,000 years ago is when the Sahara Desert started to become a desert.
To imagine the full extent of this, these glaciers covered Canada (3.84 million square miles). To give you a proper prospective, the Malaspina Glacier, which is the largest piedmont glacier in North America covers 850 square miles. That is about .02% of the glaciers covering Canada 18,000 years ago due to a small tilt in the earth’s orbit of the sun. Not to mention the glaciers where often nearly 2 miles thick. From 18,000 years ago until 6,000 years ago Canada would lose roughly 300 square miles of glacier surface a year. To give you an idea of how huge this was, all the glaciers in Montana cover about 26 square miles.
This entire area is about 8 percent surface area of the annual glacier retreat from 18,000 years ago until 6,000 years ago. It is also estimated that these glaciers in Montana may have lost 39% of their size in the last 50 years. Which means these glaciers may have covered around 42 square miles over 50 years ago. That gives them a retreating rate of about .85 square miles a year, which is about 3% of the glacier retreat 18,000 to 6,000 years ago. However, that is only surface area and not volume.
Today’s glaciers in Colorado are about .13 miles to .29 miles thick. If you use this average of Colorado glacier thickness as a rough estimate to calculate the volume of ice lost in Montana you get about a loss of about .18 cubic square miles of ice retreat each year. If you average the Canada glaciers to have about an one mile thickness, the annual volume loss of ice in Montana is about 0.06% of the annual volume loss of ice in Canada 18,000 to 6,000 years ago. I am certain there is more precise estimates available to compare the glaciers of that time to current events, but the take home message is that there was massive climatic changes happening 18,000 to 6,000 years ago that dwarf current events. Here is what California would have looked like 18,000 years ago. Notice an extended cost line, massive mountain glaciers, and huge lakes covering the eastern side of the state.
Nor were the Ice Age lakes isolated to California, here is a picture of Lake Lahontan in modern day Nevada as it may have existed 12,700 years ago. This lake receded until it was gone 9,000 years ago. This lake also teamed with Lahontan Trout that filled the lake and its tributaries. The picture below illustrates massive lakes that covered the western landscape throughout California, Nevada, Utah, Montana, Oregon, Idaho, and Washington 17,000 years ago. The red arrows shows the path of a paleo megaflood’s referred to the Bonneville flood. These massive lakes were the result of the ice age’s cooler temperatures and ice melt. Around 17,400 years ago the waters of Bonneville ripped through a sedimentary bedrock dam which
was 5,000 feet tall and 340 feet thick releasing 850 cubic square miles of water at a rate almost 4,000 times higher than the average flow of the Colorado River.
was 5,000 feet tall and 340 feet thick releasing 850 cubic square miles of water at a rate almost 4,000 times higher than the average flow of the Colorado River.
But, this flood was not even the biggest, the Lake Missoula flood happened about 15,000 years ago when an ice dam breached. All of this might be very impressive to most people. The amazing part is; may of these massive ancient paleohydrological events were a feed back response to orbital variations in how the earth rotates around the sun. As we go into the future, scientist are trying to understand our past to understand our future. As the tilt of the earth is currently shifting back, what should we expect? Could we see droughts, animal migration or behavior changes, and increase in precipitation in places due to orbital variation? Is this being factored in enough in current climate modeling?
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An example of an interstadial similar to current climate events is an inter-glacial event that happend roughly 130,000 to 115kya years ago known as the Eemian. During the Eemian the global temperature were several degrees Celsius higher than it is today and the oceans were 20-30 feet deeper. This of course is not even considered an anomaly, it is estimated that all the inter-glacial periods might have had similar climate conditions as the Eemian during the Pleistocene. In attempts to understand the current interglacial period, known as the Holocene, scientists have observed that the Eemian period is not quite like the Holocene because it had a sharper temperature increase with no Younger Dryas effect, higher temperatures, and a temperature peak lasting less then 10,000 years. Some of the reasons for this are explained by eccentricity,
“The orbital eccentricity of an astronomical object is a parameter that determines the amount by which its orbit around another body deviates from a perfect circle. A value of 0 is a circular orbit, values between 0 and 1 form an elliptic orbit, 1 is a parabolic escape orbit, and greater than 1 is a hyperbola.”
“Eccentricity is important because it regulates the strength of polar maximum summer insolation caused by precession of the equinoxes every 21,000 years. Precession determines the distance from the sun during a Polar summer. If summer coincides with the earth’s perihelion then summer insolation can be up to 20% higher than average. However if the earth’s orbit is nearly circular, as it is today, then precession has little effect at all. That is why we have about 12000 years left before cooling begins.” October 4, 2016 by Clive Best, When is the next ice age due?
“The orbital eccentricity of an astronomical object is a parameter that determines the amount by which its orbit around another body deviates from a perfect circle. A value of 0 is a circular orbit, values between 0 and 1 form an elliptic orbit, 1 is a parabolic escape orbit, and greater than 1 is a hyperbola.”
“Eccentricity is important because it regulates the strength of polar maximum summer insolation caused by precession of the equinoxes every 21,000 years. Precession determines the distance from the sun during a Polar summer. If summer coincides with the earth’s perihelion then summer insolation can be up to 20% higher than average. However if the earth’s orbit is nearly circular, as it is today, then precession has little effect at all. That is why we have about 12000 years left before cooling begins.” October 4, 2016 by Clive Best, When is the next ice age due?
In order to compare current climate changes to the past we need to look at an interglacial period with a similar eccentricity. Two observations from these charts come to play. The first is the current interglacial period, Holocene, is only half over. And if the Holocene is anything like the Anglian interglacial period temperatures are set to continue to rise if they correlate with EPICA (European Project for Ice Coring in Antarctica) temperatures reported for the Anglian interglacial period.
"We can argue about how warm the peak temperature will get and CMIP5 models vary about this roughly between 2 and 5 degrees. However this manmade climate disturbance should last for not much more than 3000 years so long as our emissions are reduced before 2100. The real question is what level we should then try to keep CO2 to avoid another devastating glaciation in 13,000 years time? If we want to survive long term then probably we should never let CO2 fall below 300ppm ever again!"October 4, 2016 by Clive Best, When is the next ice age due?
"We can argue about how warm the peak temperature will get and CMIP5 models vary about this roughly between 2 and 5 degrees. However this manmade climate disturbance should last for not much more than 3000 years so long as our emissions are reduced before 2100. The real question is what level we should then try to keep CO2 to avoid another devastating glaciation in 13,000 years time? If we want to survive long term then probably we should never let CO2 fall below 300ppm ever again!"October 4, 2016 by Clive Best, When is the next ice age due?
NOAA shows a modest 3.2 mm sea level rise over the last year. How significant is the current sea level raise from a geological perspective? May 26 2018-Recently in the Meeting minds article, “A Climate Change Perspective – Relating Things to the Early Holocene and Eemian”, we reported that the last 2 years the oceans have suspended rising. However, recently from NOAA has reported a modest sea rise increase.
Exactly how fast are the oceans rising? Reported in, “A Climate Change Perspective – Relating Things to the Early Holocene and Eemian"
Since 1880 the ocean began to rise briskly, climbing a total of 210 mm (8.3 in) through 2009- about 7 inches a century. However, if you put that in a historical perspective; 19,000 to 6,000 years ago the sea level raise rate was roughly 529% to 2814% higher then today. Oceans during this time raised close to 120 metres (4,724 inches), this would be 56,915% percent larger then the 8.3 inch sea level raise since 1880. This all happened from 18,000 to 4,000 years before the birth of Jesus.
National Oceanography Centre
"Global sea level rose by a total of more than 120 metres as the vast ice sheets of the last Ice Age melted back. This melt-back lasted from about 19,000 to about 6,000 years ago, meaning that the average rate of sea-level rise was roughly 1 metre (37 inches) per century. Previous studies of sea-level change at individual locations have suggested that the gradual rise may have been marked by abrupt ‘jumps’ of sea-level rise at rates that approached 5 (197 inches) metres per century. Their analyses indicate that the gradual rise at an average rate of 1 metre per century was interrupted by two periods with rates of rise up to 2.5 metres (98 inches) per century, between 15 and 13 thousand years ago, and between 11 and 9 thousand years ago."
The Graph below represents estimated sea level over the last 500 million years. You will see in the left hand side where the current Holocene is located. Sea level heights over the last 25 million years compared to the last 500 million years is roughly lower then ninety percent of time. Slightly different estimates exist based on different sources of analysis and evidence. So, the graphs in this article should be taken as rough estimates.
Since 1880 the ocean began to rise briskly, climbing a total of 210 mm (8.3 in) through 2009- about 7 inches a century. However, if you put that in a historical perspective; 19,000 to 6,000 years ago the sea level raise rate was roughly 529% to 2814% higher then today. Oceans during this time raised close to 120 metres (4,724 inches), this would be 56,915% percent larger then the 8.3 inch sea level raise since 1880. This all happened from 18,000 to 4,000 years before the birth of Jesus.
National Oceanography Centre
"Global sea level rose by a total of more than 120 metres as the vast ice sheets of the last Ice Age melted back. This melt-back lasted from about 19,000 to about 6,000 years ago, meaning that the average rate of sea-level rise was roughly 1 metre (37 inches) per century. Previous studies of sea-level change at individual locations have suggested that the gradual rise may have been marked by abrupt ‘jumps’ of sea-level rise at rates that approached 5 (197 inches) metres per century. Their analyses indicate that the gradual rise at an average rate of 1 metre per century was interrupted by two periods with rates of rise up to 2.5 metres (98 inches) per century, between 15 and 13 thousand years ago, and between 11 and 9 thousand years ago."
The Graph below represents estimated sea level over the last 500 million years. You will see in the left hand side where the current Holocene is located. Sea level heights over the last 25 million years compared to the last 500 million years is roughly lower then ninety percent of time. Slightly different estimates exist based on different sources of analysis and evidence. So, the graphs in this article should be taken as rough estimates.
Below is a graph the shows the estimated sea level over the past 450 thousand years. The Red circle shows where the Holocene is and where the modern human era is located. What stands out when you look at this graph is that over the last 450 thousand years there are potentially 7 peaks where the sea level was slightly higher than the current conditions. Also, what is intriguing is the sea level raised 120 meters increase, starting 20 thousand years ago, before human beings started altering the climate.
As you look over the data above you may wonder what is causing the peaks and troughs following a repeating sequence? We show in “Glaciers or Rising Oceans; Damned if you do, damned if don’t, And Maybe Both” that these peaks are caused by
“Modern science has discovered that orbital variation known as the Milankovitch cycle have been causing these milder events known as interstadials. Climate change driven by Orbital variation may not be limited to the Ice Age. It has been observed that orbital variation may have been a very important driver for climate change for 1.4 billion years .”
Below we show two graphs. The top graph compares sea level over the last one million years and the bottom graph compares sea level rise over the last 140 thousand years.
“Modern science has discovered that orbital variation known as the Milankovitch cycle have been causing these milder events known as interstadials. Climate change driven by Orbital variation may not be limited to the Ice Age. It has been observed that orbital variation may have been a very important driver for climate change for 1.4 billion years .”
Below we show two graphs. The top graph compares sea level over the last one million years and the bottom graph compares sea level rise over the last 140 thousand years.
Even though the graph above only shows one million years the current Pleistocene started roughly 2.5 million years ago. We just transcribed in this article above that the current sea level may have been higher at potentially 7 or more peaks the last 450 thousand years depending on source of information. However, if you look at the graph below you will observe that the sea level was potentially higher than current conditions almost 16 times between 2.5 million years ago and 1 million years ago. Not only that; we report in "Glaciers or Rising Oceans; Damned if you do, damned if don’t, And maybe both”
Remarkably,
“There is even evidence that Greenland may have been ice free for 280,000 years about 1.1 million years ago. What is even more remarkable is that many ice age mega fauna that went extinct 11,000 years ago survived the previous interstadials even though the oceans were higher and the temperatures were warmer; forests reached North Cape, Norway….”
It is astounding to think that 1.2 million years ago Greenland may have been ice free for 280 thousand years…
Remarkably,
“There is even evidence that Greenland may have been ice free for 280,000 years about 1.1 million years ago. What is even more remarkable is that many ice age mega fauna that went extinct 11,000 years ago survived the previous interstadials even though the oceans were higher and the temperatures were warmer; forests reached North Cape, Norway….”
It is astounding to think that 1.2 million years ago Greenland may have been ice free for 280 thousand years…
Below is a graph the shows the sea level over the last 20 thousand years in relation to current conditions in meters. Below is a graph that shows the increase of the sea level as a rate measured in centimeter per century. As you can see in the graph below the large blue box is the natural variation and the small red circle is recent history where modern humans started to alter the environment.
Below is a similar graph as above, showing the sea level rise as a rate measured by cm per century? If you look at the bottom right hand corner you will see the arrow that leads to another graph that shows the sea level rise over the last 140 years. It is estimated that the oceans have risen about 8 inches since 1880. One may be concerned if an eight inch sea level rise happened in the last 20 years, but the sea has only risen roughly 3.5 inches in the last 30 years.
Meeting Minds does not deny climate change or the fact that humans are altering the ecosystem of the world. However, one of the most asked question is; what percent of the ocean rise in the last 30 years is natural vs human caused. MOTM reported in “Glaciers or Rising Oceans; Damned if you do, damned if don’t, And Maybe Both”
In the graph below we would like to draw your attention to the small red circles. These circles represent potential glacier peaks over the last 450 thousand years; including 20 thousand years ago. If you follow the arrows from those circles to the next picture you will see an illustration of what North America potentially looked like during those time periods. You will notice that almost half of North America was covered in glaciers during these time periods. These huge extreme climatic changes most likely happened because of very small orbital variations in earth’s rotation around the sun.
In the graph below we would like to draw your attention to the small red circles. These circles represent potential glacier peaks over the last 450 thousand years; including 20 thousand years ago. If you follow the arrows from those circles to the next picture you will see an illustration of what North America potentially looked like during those time periods. You will notice that almost half of North America was covered in glaciers during these time periods. These huge extreme climatic changes most likely happened because of very small orbital variations in earth’s rotation around the sun.
We would like to conclude in this article by asserting our stance that Humankind is altering many ecosystems in the world, degrading natural reference state habitats, and having an unknown effect on the climate. And it is almost beyond a shadow of doubt that Carbon Dioxide Emissions have increase about 50% from 280 ppm to about 410 ppm. However, we would like to point out that this number is not set in stone and is in flux due to; seasonal variations, loss of natural carbon sequestration sinks from deforestation, and thawing of the permafrost in the arctic. However, as we pointed out above, with the Anglian Glacier Analog, temperatures might continue to moderately increase naturally. Furthermore, some warming may be related to urbanization, deforestation, orbital variation cycles, natural weather cycles, and etc. But, how does this compared to temperature changes at the beginning of the current interglacial period? We recently reported in ,” Glaciers or Rising Oceans; Damned if you do, damned if don’t, And Maybe Both”