Research provides new theory on cause of ice age 2.6 million years ago

From Royal Holloway, University of London

New research published today (Friday 27th June 2014) in the journal Nature Scientific Reports has provided a major new theory on the cause of the ice age that covered large parts of the Northern Hemisphere 2.6 million years ago.

The study, co-authored by Dr Thomas Stevens, from the Department of Geography at Royal Holloway, University of London, found a previously unknown mechanism by which the joining of North and South America changed the salinity of the Pacific Ocean and caused major ice sheet growth across the Northern Hemisphere.

The change in salinity encouraged sea ice to form which in turn created a change in wind patterns, leading to intensified monsoons. These provided moisture that caused an increase in snowfall and the growth of major ice sheets, some of which reached 3km thick.

The team of researchers analysed deposits of wind-blown dust called red clay that accumulated between six million and two and a half million years ago in north central China, adjacent to the Tibetan plateau, and used them to reconstruct changing monsoon precipitation and temperature.

“Until now, the cause of the Quaternary ice age had been a hotly debated topic”, said Dr Stevens. “Our findings suggest a significant link between ice sheet growth, the monsoon and the closing of the Panama Seaway, as North and South America drifted closer together. This provides us with a major new theory on the origins of the ice age, and ultimately our current climate system.”

Surprisingly, the researchers found there was a strengthening of the monsoon during global cooling, instead of the intense rainfall normally associated with warmer climates.

Dr Stevens added: “This led us to discover a previously unknown interaction between plate tectonic movements in the Americas and dramatic changes in global temperature. The intensified monsoons created a positive feedback cycle, promoting more global cooling, more sea ice and even stronger precipitation, culminating in the spread of huge glaciers across the Northern Hemisphere.”

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68 Responses to Research provides new theory on cause of ice age 2.6 million years ago

  1. JimS says:

    New theory, eh? Why is that I have known about this theory long before this paper was published?

  2. milodonharlani says:

    It has long been known that the onset of the Pleistocene glaciations was associated with the formation of the Isthmus of Panama, but rearrangement of ocean currents was thought the main culprit behind ice sheet formation.

  3. Taphonomic says:

    A link to the full article (not paywalled!).

    http://www.nature.com/srep/2014/140627/srep05474/full/srep05474.html

  4. JimS says:

    I think I will dig up well known but rarely discussed climate theories and sell them off to universities to recycle. I get paid for them, and the universities and/or scientific organizations get the grants from the government. Everyone is satisfied and rich. Is this the American way, now?

  5. Since North and South America are still joined (Panama canal could have little effect) why aren’t we still in an ice age if this was the cause for the one 2.6 million years ago?

  6. mkelly says:

    Myron Mesecke says:

    June 27, 2014 at 9:48 am

    … why aren’t we still in an ice age if this was the cause for the one 2.6 million years ago?

    ==================

    We are still in an ice age.

  7. FerdinandAkin says:

    See! See! The activities of man are causing global warming. We dug the Panama Canal and the planet started to heat up. The only solution to this is to raise taxes, fill in the canal, end the commerce of all products transported by ship, and raise taxes. The prices for food and consumer products will necessarily skyrocket because of this, but it will be compensated for by raising taxes.

  8. Jimbo says:

    Surprisingly, the researchers found there was a strengthening of the monsoon during global cooling, instead of the intense rainfall normally associated with warmer climates

    It’s always a surprise isn’t it.

  9. philjourdan says:

    The positive feedback loop has been found! Unfortunately it does not portend more warming.

  10. JimS says:

    The Panama Canal uses an internal lake and waterway system for the route between the two oceans. The Pacific and Atlantic are not really joined by the canal. A large portion of the Isthmus would have to be completely removed, and the water would probably have to be at least at a 200 metre depth to have a positive effect of stopping this present Ice Age. There is a mountain range on the Isthmus, so it is not a practical engineering feat even with our current resources, knowledge and energy. However, if such a feat was ever achieved, it would probably initially affect the ocean currents and send the planet into another glaciation period for thousands and thousands of years until equilibrium was established again. It would eventually end this Ice Age, but the SA plate is still pushing northward so the Isthmus would form again.

  11. My first visceral reaction was, “Dept. of Geography…” [red alert! it is either nonsense or very old news]
    Yep. Closing of the Isthmus is very old news.

    Now the idea the increased monsoons can change the surface salinity of the surface waters of Northern Pacific is an interesting idea in that it at once makes the ocean surface easier to freeze and the increased moisture increases snow accumulation rates.

    HOW monsoons can do this to the North Pacific, the critical hypothesis, doesn’t get the focus it needs.

    Until now, the cause of the Quaternary ice age had been a hotly debated topic”, said Dr Stevens

    Wrong. It still is. Dr. Stevens hasn’t changed it much.

  12. Latitude says:

    Surprisingly….good grief

  13. JimS says:

    <>

    Oh please, Dr. Stevens, it is hardly a discovery. It makes me wonder how scientists get their credentials these days being so absolutely clueless regarding previous scientific research and published papers.

  14. evanmjones says:

    Well, you have to cut these guys some slack. There are always new papers out on old subjects, some of which (may) represent a valuable contribution. (After all, they re still paying for papers that show that men are not — or are — exactly the same as women.)

  15. Barbara Skolaut says:

    “It makes me wonder how scientists get their credentials these days being so absolutely clueless regarding previous scientific research and published papers.”

    I’d say “out of a Cracker Jack box,” but I don’t want to insult caramel popcorn.

  16. mpainter says:

    I agree with Meseke above. Conditions have not changed, the isthmus is still there, so why no glaciation? The answer to the puzzle lies elsewhere. The most important fact is the sudden onset of warming. Any theory that does not explain this plausiblly does not work. And please, do not shift the ocean currents around like pieces on a chessboard.

  17. Speaking of changing ocean current…
    Is there today any appreciable ocean current heat transport through the Bering Straits? If there is, then because of the broad area and shallow depth, a small change in sea level radially alters the heat flow. I think the situation has some strong elements of positive feedback, at least until the Arctic Ice Cap is attenuated.

    Beware of assumptions in models: from: On the Flow Through Bering Strait: A 1 Synthesis of Model Results and Observations by Kinney and Maslowski, et. al. (post 2008)

    In an effort to
    176 balance the net flow of Pacific Ocean water into the Arctic Ocean, a U-shaped 500 m
    177 deep, 162 km (18 grid point) wide channel was created through North America
    178 connecting the Atlantic Ocean to the Pacific Ocean. A westward wind forcing of 1.75
    179 dyne cm-2 is prescribed along the channel (see Maslowski et al. 2004 for further details).
    180 Flow through the Bering Strait and the channel is not prescribed.

    Square peg, round hole, meet hammer.
    Figure 10b has some data on measured Heat Flux based on ?one? bouy from 1979 to 2004. on the order of 4*10*20 J/yr (or 0.4 ZJ/yr)

  18. D. Cohen says:

    “The Panama Canal uses an internal lake and waterway system for the route between the two oceans. The Pacific and Atlantic are not really joined by the canal. A large portion of the Isthmus would have to be completely removed, and the water would probably have to be at least at a 200 metre depth to have a positive effect of stopping this present Ice Age. There is a mountain range on the Isthmus, so it is not a practical engineering feat even with our current resources, knowledge and energy. ”

    I’m not suggesting we do anything like this, understand, but I’m not convinced that obliterating the isthmus of panama is beyond our present technological capabilities. Take one — or several — moderate sized asteroids, deflect their orbits so they are aimed at Panama cutting across the isthmus, and wait for them to hit. Repeat as necessary. I think that would do it, and at surprisingly little cost — if no one worries about compensating present-day Panamanians for losing their country…

  19. G. Karst says:

    mkelly says:
    June 27, 2014 at 9:55 am

    We are still in an ice age.

    How easy it is for some to forget this salient fact. We should be grateful for every little bit of warming, we can muster. GK

  20. Katou says:

    The kids used to make me feel the same way as the Pro AGW proponents do .I just want to give up and shut my mouth, because no amount of arguing or reason will convince them that that triple dip cone from Dairy Queen will have a effect on their supper . Some times it sure feels that the battle will be lost no matter what .

  21. tadchem says:

    Now how do we say that rising CO2 is causing plate tectonic movement???

  22. Pam Uphoff says:

    Ice Ages, sometimes referred to as Ice Epochs, are time periods, millions of years long, that have ice caps on polar landmasses (see Antarctica and Greenland). They are marked by long periods (100,000 yrs) of extensive ice and glaciers advancing well beyond the arctic circle, also frequently referred to as “ice ages,” interspersed with brief (12,000 yrs) warm periods, called interglacials, when the ice retreats toward the poles. We are currently in an interglacial.

    Just because NYC isn’t being threatened by glaciers doesn’t mean the Ice Age is over. There’s still _plenty_ of ice. As we’re 11,500 years into the interglacial, warming is not my biggest worry.

  23. Matt Skaggs says:

    JimS is right. From wikipedia:

    “The closing of the Isthmus of Panama about 3 million years ago may have ushered in the present period of strong glaciation over North America by ending the exchange of water between the tropical Atlantic and Pacific Oceans.[48]

    Reference [48] dates from 1996 (secondary source, don’t bother).

  24. phlogiston says:

    Notice again the myopic focus on the atmosphere – monsoons etc., and fear of mentioning ocean currents. Mentioning the ocean to in-vogue climate scientists seems to be like mentioning the war to Germans – the result is stony silence.

    Guys – there’s an ocean out there that determines our climate. Come on in – don’t be scared of the water!

    “Strengthening of monsoons during global cooling” – that’s curious, normally folks consider coolness to equal dryness.

  25. D.J. Hawkins says:

    @JimS says:
    June 27, 2014 at 10:08 am

    @D. Cohen says:
    June 27, 2014 at 10:50 am

    Google “Operation Plowshare” and “Pan Atomic Canal”. There is no doubt in my mind that a sea-level canal is technically feasible. Politically feasible is an entirely different kettle of fish.

  26. Sun Spot says:

    @mkelly says:June 27, 2014 at 9:55 am
    @G. Karst says:June 27, 2014 at 10:52 am

    Why are there inter-Glacial s and why are we in one now ?

  27. JimS says:

    @Sun Spot

    The glacial and inter-glacial periods of this present Ice Age, which have been going on for about 3 million years seem to be controlled by the Milankovitch cycles. We are in an inter-glacial episode now because 3 of these cycles, about 12,000 years ago gave close to maximum insolation to the earth, AT THE Northern Hemisphere LATITUDES. The key is what happens in the northern hemisphere, because that is where two huge ice sheets grow during a glacial episode. Such episodes last for 90,000 years or more. Look up the “Laurentide Ice Sheet” to see how extensive the ice sheet on North America can be – 5 million square miles at its peak.

  28. JimS says:

    @ D J Hawkins
    ‘Google “Operation Plowshare” and “Pan Atomic Canal”. There is no doubt in my mind that a sea-level canal is technically feasible. Politically feasible is an entirely different kettle of fish.’

    Thanks. I will look these up. The reason for my interest is because I had to research this area for a short story I was writing a couple of months ago. Whatever more I can learn, I am very grateful. Thanks again.

  29. Tom G(ologist) says:

    Duh!!!!!!! Who are they kidding? Everyone has known about that and its impacts on global circulation and sea chemistry changes for DECADES.

    But of course I know who they are kidding – everyone who is NOT a geologist.

  30. milodonharlani says:

    mpainter says:
    June 27, 2014 at 10:44 am

    We are still a glacial epoch. The Holocene, ie the past ~11,000 years, is just the latest of many interglacial intervals. The glacial phases last much longer than interglacials, averaging about 100,000 years. The cycles (named after Milankovitch) of longer glacials & shorter interglacials are largely controlled by orbital & rotational parameters, such as the eccentricity of earth’s orbit.

    Earth has been in an “Icehouse” for about 38 million years. Before then, the planet was largely ice free. During the Oligocene, ice sheets formed over Antarctica. They contracted a bit during the following Miocene, but with the closure of Panama, they not only grew bigger there, but occurred in the Northern Hemisphere. Greenland of course still has its ice sheet, but during interglacials the North American, European & Asian ice sheets melt. During the longest, warmest integlacials, like MIS 11, even the southern dome of the Greenland ice sheet thaws.

    The northern continental ice sheets will return in a few thousand to at most some tens of thousands of years.

    Icehouse & “Hothouse” intervals alternate in earth history. Most of the Mesozoic & the early Cenozoic (Paleocene & Eocene Epochs) were a Hothouse world, without ice at the poles. The Late Carboniferous & Early Permian Periods were an Icehouse, & in the middle of the Mesozoic there was a mild Icehouse (around the Jurassic/Cretaceous boundary). That cold snap was followed by amazingly warm times in the mid-Cretaceous.

    Climate is cyclic & self-regulating.

  31. Gary Pearse says:

    What is a geographer doing tackling the cause of the ice age. People with a knowledge of science have been trying to figure this all out for 150 years since Louis Agassiz first recognized that there had been ice ages at all. Changed salinity? Which way did it go? Now let me do some research:

    http://en.wikipedia.org/wiki/Pliocene

    “The formation of the Isthmus had major consequences on global temperatures, since warm equatorial ocean currents were cut off and an Atlantic cooling cycle began, with cold Arctic and Antarctic waters dropping temperatures in the now-isolated Atlantic Ocean.”

    Hmmm….probably the same source that our grapher of the geo got his inspiration. But note, this cooled the Atlantic waters because of the “..cold Arctic and Antarctic waters”. So it was already cold in the Arctic and Anarctic. And, with the Isthmus still joining us, what made the ice go away again. With the big names’ ‘hiatus’ in climate research, we are getting a lot of bottom feeders getting into the act.

  32. Robert W Turner says:

    “The team of researchers analysed deposits of wind-blown dust called red clay” HAHA, that IS what a geographer would call it.

    @Jim, why do you presuppose that if a manmade seaway were dug in Panama that the world would immediately enter a glacial period?

    The area where the canal is built appears to be a major syncline, hence the large lake, and elevations are around 200 m at most in the area. Looking at a detailed motion of the plates it appears that area may be wrenching apart, giving Panama its shape and topography.
    http://peterbird.name/publications/2003_PB2002/2003_PB2002.htm

    Considering how difficult it was to build a canal through panama, building a seaway that allowed sufficient circumequatorial currents to exist seems impossible.

  33. JimS says:

    @Robert W Turner
    “@Jim, why do you presuppose that if a manmade seaway were dug in Panama that the world would immediately enter a glacial period?”

    It is more than likely that if the Pacific and Atlantic oceans were once again united as one ocean in the tropical zone, that this would greatly upset the current thermohaline circulation. The result could mean a destabilization of the entire world climate for a few thousand years or more. It is my guess that when the world’s climate becomes upset, it reverts to its default, and currently its default position is a glaciation period since we are currently living within an Ice Age – nothing scientific here – just a hunch.

  34. James McCown says:

    milodonharlani says:

    Earth has been in an “Icehouse” for about 38 million years. Before then, the planet was largely ice free.

    I thought the pleistocene ice age began about 3 million years ago? Please forgive me if I am missing something.

    Also, weren’t there earlier “Icehouses” such as the Huronian and Cryogenian ice ages during the proterozoic?

  35. milodonharlani says:

    Gary Pearse says:
    June 27, 2014 at 1:06 pm

    Not all the ice has gone away. Because we’re in a warmer interglacial, the Laurentide, Scandinavian & Siberian ice sheets have retreated or melted, but the ice sheets will return, as they periodically have done for about 2.6 million years.

    The Pleistocene & Holocene are just a colder episode in the already cooler than the Phanerozoic average Icehouse that began at the Eocene/Oligocene boundary, when Antarctica was fully cut off by deep ocean channels from South America & Australia.

  36. milodonharlani says:

    James McCown says:
    June 27, 2014 at 1:32 pm

    As I just wrote above, the Pleistocene began about 2.6 million years ago, but earth was already in an Icehouse, which basically means a time in geologic history during which ice sheets exist, plus any montane glaciers grow bigger. The Pleistocene & Holocene Epochs have been colder than the Oligocene, Miocene & Pliocene, but all count as an Icehouse, since before the Quaternary (Pleistocene & Holocene) glaciations of the northern hemisphere, Antarctica was already covered by extensive ice sheets.

    The present Icehouse (from c. 38 Ma to now) followed a very warm Hothouse during the Cretaceous Period & Paleocene & Eocene Epochs of the Paleogene Period (replacing the Tertiary) the Cenozoic Era. Peak warmth during that Hothouse occurred during the mid-Cretaceous & at the Paleocene-Eocene Thermal Maximum (PETM), when alligators thrived in Alaska.

  37. milodonharlani says:

    PS: Yes, there have been Icehouses more serious than our current one, including the Huronian (2.4 to 2.1 Ba) & at least three other “Snowball Earth” episodes during Cryogenian (850 to 635 Ma). The current Phanerozoic Eon has seen at least three major & one minor intervals of glaciation, ie at the Ordovician/Silurian boundary (when CO2 was in the thousands of parts per million), the Late Carboniferous & Early Permian, the lesser episode at the Jurassic/Cretaceous border, & the present Cenozoic one.

  38. emsnews says:

    Anything to hide the truth!

    The yo-yo from very cold to somewhat warm has been happening repeatedly. ALL Ice Ages begin suddenly and all go into Interglacial melting SUDDENLY, too.

    The only mechanism that can do this trick is the sun. When the sun is shedding lots of heat, we heat up here on earth. When it ceases and there are virtually no sun spots, it gets really really cold.

    End of story. The configuration of the landmasses may amplify the surges and withdrawal of energy from the sun but they don’t cause the instability itself.

  39. DocMartyn says:

    The idea that the movements of continents can make a difference to the global average temperature makes a mockery of the whole energy budget cartoons.

  40. Philip Mulholland says:

    D. Cohen says: June 27, 2014 at 10:50 am

    Take one — or several — moderate sized asteroids, deflect their orbits so they are aimed at Panama cutting across the isthmus, and wait for them to hit. Repeat as necessary.

    Nature has already done this experiment for us.
    The Chicxulub Impact
    The results were not nice.

  41. JohnTyler says:

    Weren’t there several ice ages?
    How many times did North and South America marry and get divorced?
    What about the Medieval Warm Period? Did that occur when N. and S. America decided to take some time apart to find themselves?

  42. JimS says:

    @JohnTyler

    There were several ice ages. The one we are in now has lasted from 2.5 to 3 million years.

    At one time South America was joined with Antarctica, but the South American plate drifted north and broke from Antarctica and pushed into North America. To my knowledge, the South American plate is still pushing north, so Brazil may butt into the Gulf of Mexico in 50 million years or so. Who really knows.

    The Medieval Warm Period occurred just 1,000 years ago. There are warm and cool periods within any interglacial period like the one we are in today. Right now, we are experiencing another warming period as we did 1,000 years ago. These are “minor” warming periods on the larger geological scale without the need for major geological changes to initiate them. We really do not know what controls the climate, but we can only guess. It is a good bet though, that the formation of the Isthmus of Panama started this present Ice Age.

  43. thingadonta says:

    Continental configuration, who’d a thought?

    By the way, ever noticed that Africa, South America, North America, Australia are all upright N-S? Chances of this at random is very low. Only few places which aren’t upright are volcanic New Zealand, Japan, Central America, Indonesia etc.

    Centrifugal force?

  44. James the Elder says:

    D.J. Hawkins says:
    June 27, 2014 at 11:16 am
    @JimS says:
    June 27, 2014 at 10:08 am
    @D. Cohen says:
    June 27, 2014 at 10:50 am
    Google “Operation Plowshare” and “Pan Atomic Canal”. There is no doubt in my mind that a sea-level canal is technically feasible. Politically feasible is an entirely different kettle of fish.
    ===========================================================================
    We may know soon enough.

    http://www.washingtontimes.com/news/2013/jul/15/chinese-tycoon-plans-to-rival-panama-canal-with-40/?page=all

  45. I have no idea how old the theory about how the joining of the North and South America continents changed the climate enough to start up the current ice age we’re in, but one of my geology professors in the late 70s was tossing around the same concept to us undergrads.

  46. cynical_scientist says:

    They figured all that out by digging up some clay in Northern China? Impressive. Seldom have such large conclusions been drawn from so little data since the days when little old ladies calculated how many kids you were going to have by looking at tea leaves.

  47. thingadonta says:

    Walt Stone
    “I have no idea how old the theory about how the joining of the North and South America continents changed the climate enough to start up the current ice age we’re in,”

    I think you will find that it’s part of a general pattern: the temperature differential between the poles and equator has a lot to do with ice ages.

    If the continents are joined, there is less heat exchange between the pole and equator, meaning greater temperature differential and more ice at the poles. If North and South America join, this is part of that process I suspect.

    Restrictive ocean circulation is one of the factors reducing heat exchange. It also helps if you have a lot of continent about the poles to build up ice to begin with and restrict circulation, meaning once again, you get more ice. Antarctica, Greenland and North America as well as Russia is a lot of land about the poles. Africa is slowly joining Europe (as well as Arabia, both joining Eurasia) meaning oceanic circulation is decreasing there also, the Mediterranean will close entirely in a few million years. Australia moving north is closing the circulation with Indonesia and SE Asia as well, as well as setting up the circumpolar current in the southern ocean. India has joined Asia closing the Tethys Ocean. All these factors have likely cooled the earth over the last 50 million years or so, because they all reduce heat exchange between the tropics and the poles, as well as allowing ice to build up over continents near the poles.

    If the poles are cooler and the tropics warmer, the earth is the same average heat as if the temperature was all the same the world over, except that with extra ice at the poles this reflects sunlight so it will actually be slightly cooler on average when the temperature differential is high.

    This process is self reinforcing, as they also think one of the triggers into an ice age is when ice doesn’t melt in summer, so its cooler summers that trigger an ice age and not so much cooler winters, because of the ice albedo effect. Ice that doesn’t melt in summer keeps building up and up causing runaway cooling, whereas if it even just melts this doesn’t occur, so it is indeed one of nature’s tipping points.

    Other possible factors include: the tropics are buffered against heating due to excess water vapour, meaning that isn’t so much how warm the tropics are, but how cool the poles are that triggers an ice age, the tropics will only be so warm and not much more, the poles can keep cooling indefinitely. Some have also suggested the Himalayas might have cooled the earth with the extra weathering going on (removing C02), as well as blocking heat from the Indian Ocean to central Asia.

    So we have:
    -continents which are joined tend to reduce ocean circulation and heat exchange, meaning more ice at the poles increasing ice albedo and reducing overall earth temperature,
    - more continents near the poles are able to build up ice (particularly where ice over land doesn’t melt in summer) as well as restrict heat exchange with the tropics,
    -oceans and seas which close generally reduce heat transfer (Tethys, Mediterranean, SE Asia, N and S America),
    -a circum polar current also reduces heat exchange (meaning we have both a lot of land at the poles as well as a circum polar current in different hemispheres, which might be ideal for an ice age to develop)
    -possible excessive high mountain ranges also reduce heat transfer as well as increase ice albedo.

    It seems the earth has been gradually getting cooler due to many convergent factors over the last 50 million years or so, but if you ask an alarmist they get it round the wrong way-they will answer that c02 has reduced in the atmosphere over the last 50 million years, which is an effect, not a cause.

  48. TomRude says:

    The relation with atmospheric circulation as described on their figure 1 does not inspire any confidence in their conclusion.

  49. michael hart says:

    So how often does an IPCC model produce an ice age?

  50. Larry Fields says:

    Perhaps the study by Stevens et. al. (together with similar earlier work) is news that we can use. How so?

    Suppose that 500 years from now, we find ourselves descending into the next major glacial advance, aka ‘ice age’. One rational response would be a massive geo-engineering project to resurrect the Panama Seaway, in order to affect oceanic circulation. This should warm the planet enough that Canadians, Chicagoans, and Northern Europeans would not become climate refugees.

    Of course, geo-engineering on this scale would not be cheap. There would be obvious secondary costs. We’d need to construct nice condos in Florida, to expedite U.S. citizenship, and to provide ESL classes and job training for approximately half of all Panamanian families.

    Nicaragua is considering the construction of a secondary canal. We should encourage and partially fund such a project, albeit on a much larger scale than was originally proposed.

    Funding for environmental mitigation may also be needed in both countries.

  51. Lars P. says:

    Myron Mesecke says:
    June 27, 2014 at 9:48 am
    Since North and South America are still joined (Panama canal could have little effect) why aren’t we still in an ice age if this was the cause for the one 2.6 million years ago?

    We are in an interglacial Myron:
    http://climate4you.com/GlobalTemperatures.htm#An%20overview%20to%20get%20things%20into%20perspective

    I think the salinity part is interesting also in view of the global salinity reduction that must have resulted from:
    https://en.wikipedia.org/wiki/Messinian_salinity_crisis

  52. david says:

    Talk about re-inventing the wheel!! This diminishes the excellent role that some geographers have and are making. Is Stevens a geographer? Many geography departments thee days are packed with geologists who cannot get jobs elsewhere.

  53. kadaka (KD Knoebel) says:

    From emsnews on June 27, 2014 at 4:14 pm:

    The only mechanism that can do this trick is the sun. When the sun is shedding lots of heat, we heat up here on earth. When it ceases and there are virtually no sun spots, it gets really really cold.

    Oh.

    You’re one of them.

    Why didn’t you provide your definitive evidence days ago? There are long pleasant discussions wrapping up now at another post where such evidence was explicitly requested. You could have changed the entire course of the investigation. As it was, no conclusive evidence of solar minimums causing cold periods on Earth was presented.

    http://wattsupwiththat.com/2014/06/23/maunder-and-dalton-sunspot-minima/

    There are still people keeping watch, you could take your strongest piece of evidence and present it for consideration.

    Instead all we currently have is your unbacked claims here, a drop-off posting without substantiation.

    Sadness.

  54. Bill Illis says:

    I think the closure of the Panama Isthmus should have, technically, made ice ages less likely.

    The closure diverted the equatorial current from flowing into the Pacific to flowing into the Gulf Stream (warming up the far northern Atlantic). And it also made the Atlantic more salty which provides for less sea ice development (perhaps half a degree equivalent).

    The only way I see the closure of the Isthmus causing the ice ages is that it reduced the strength of the ocean flow into the Arctic from the Pacific side (less inflow at the Panama Isthmus, less outflow into the Arctic ocean from the Pacific ocean side). This would have then reduced the outflow from the Arctic ocean into the north Atlantic through the Fram strait.

    ie. more ocean stays in the Arctic ocean for a longer period of time allowing more sea ice to build up and not just getting flushed out every year, resulting in sea ice in the summer, lowering Albedo etc.

    A more likely explanation is that continental drift moved Greenland and Ellesmere Island just that little bit farther north, so that they became succeptible to the downturns of summer solar insolation in the Milankovitch Cycles. Before 2.7 million years ago, Greenland was too far south to build up large glaciers. Greenland is drifting northwest at 3.3 cms per year (1.9 cms to the north and 1.4 cms to the west) and has been doing so for about 55 million years since splitting away from the UK about where Iceland is today. That would mean it moved north by 990 kms in that timeperiod before freezing over 2.7 million years ago. Move Greenland 200 kms farther south and it would not have glaciers. Southeast Greenland GPS station VFDG.

    http://sideshow.jpl.nasa.gov/post/links/VFDG.html

  55. phlogiston says:
    June 27, 2014 at 11:14 am

    “Strengthening of monsoons during global cooling” – that’s curious, normally folks consider coolness to equal dryness.
    —————

    The folks living in northern Europe during the Little Ice Age sure didn’t consider any such thing, to wit:

    During the LIA, there was a high frequency of storms. As the cooler air began to move southward, the polar jet stream strengthened and followed, which directed a higher number of storms into the region. At least four sea floods of the Dutch and German coasts in the thirteenth century were reported to have caused the loss of around 100,000 lives. Sea level was likely increased by the long-term ice melt during the MWP which compounded the flooding. Storms that caused greater than 100,000 deaths were also reported in 1421, 1446, and 1570. Additionally, large hailstorms that wiped out farmland and killed great numbers of livestock occurred over much of Europe due to the very cold air aloft during the warmer months. Due to severe erosion of coastline and high winds, great sand storms developed which destroyed farmlands and reshaped coastal land regions.” Source: http://www2.sunysuffolk.edu/mandias/lia/little_ice_age.html

  56. Jim G says:

    thingadonta says:
    June 27, 2014 at 6:37 pm
    “Continental configuration, who’d a thought?

    By the way, ever noticed that Africa, South America, North America, Australia are all upright N-S? Chances of this at random is very low. Only few places which aren’t upright are volcanic New Zealand, Japan, Central America, Indonesia etc.

    Centrifugal force?”

    There is no such thing. Centrifual force is an “apparent force” while the real force is called Centripetal force. Interesting thought though.

  57. JimS says:

    @Jim G

    I am not too sure what you mean by “upright” and thus, not being “upright” is also not really clear. As for volcanoes occurring in “upright” continents, I do believe that North America and South America have their fair share of volcanoes, and yet, you designate them as “upright.”

  58. emsnews says:

    About ‘proof’ that the sun is the #1 driver of ice age/interglacial events is obvious. Way back 100 years ago Dr. Hubble and my father Dr. Meinel and my grandfather, Edison Petitt, all decided that the sun is responsible for the multiple ice ages once it was established that there was more than one ice age.

    So they decided to study the sun much closer for this very reason. I don’t have to produce any online data to prove this, this information didn’t come to me via reading something, I grew up listening to them debate this very issue and know how they were thinking long ago because I lived with or near all of them!

    The fact that there was an ice age in the first place was hotly (ahem) debated during much of the 19th century. My grandfather was born back then and grew up listening to this debate.

    The shocker came at the turn of the 20th century that ice ages are periodic, not a one time accidental event. This SCARED EVERYONE and has oddly been eliminated as a fear in the last several decades for some weird reason.

    There doesn’t have to be any ‘documentation’ for this information since I am the ‘documentation’ in the first place, i.e., first hand knowledge which I am passing on although people can ignore this and demand second or third hand documentation, I suppose.

  59. buckwheaton says:

    I am waiting for some climate scientist to publish a paper on what the optimum climate is for our biosphere. The first question that would naturally flow would be where is our current trend in relation to this finding.

    That nobody seems interested in this vital comparison indicates that the climate is being studied for other purposes. Since all the urgent demands that flow from today’s climate science all converge on policy solutions that involve statism, bigger government, higher taxes, less personal liberty, the bigger picture tells me all that I need to know about “climate science”. It is socialism and Gaia worship by other means.

    I am also curious about how deep the ice got during the last several periods of glaciation of the northern hemisphere, but that is a question for another time.

  60. Ofay Cat says:

    The ocean level on the east side of the Panama Canal is a few inches higher than on the west side. This leads me to think that this is caused by the the easterly direction of the rotation of the earth. The water is ‘piling up’ on the east side. So … the flow would be east to west if Panama became an open waterway?

    Anyone?

  61. JimS says:

    @buckwheaton

    “I am also curious about how deep the ice got during the last several periods of glaciation of the northern hemisphere, but that is a question for another time.”

    The Laurentide ice sheet on North America, at its height, about 30,000 years ago was from 2 to 3 miles thick at its thickest. It extended for 5 million square miles, covering all of Canada and the northern regions of the present United States.

  62. thingadonta says:

    Jim S
    “I am not too sure what you mean by “upright” and thus, not being “upright” is also not really clear. As for volcanoes occurring in “upright” continents, I do believe that North America and South America have their fair share of volcanoes, and yet, you designate them as “upright.”

    North and South America’s volcanos are on continental crust. The crust is aligned N-S.

    I just noticed when drawing Australia at school is was hard to get it looking right (try it) and one way of doing it was to make sure the Cape of York was ‘upright’, or aligned N-S. The same goes for Chile-Argentina and South America. North America is also fairly aligned N-S, that’s partly why the Canadian Border is so straight, its easy to cut E-W across a N-S body. And so is Africa. And so is greenland. Then I noticed when drawing New Zealand it isn’t aligned N-S, and the reason-well its mostly volcanic. So is Japan. So is Hawaii. So is Indonesia. There must be something going on here. The chances of the majority of continents being aligned nearly N-S is nearly zero, yet they are. I’ve never heard anything about it though.

  63. gymnosperm says:

    In the Proterozoic glaciations the continents were seemingly clustered around the south pole. In the Ordovician glaciation the continents were more dispersed but still almost completely in the southern hemisphere. It is clearly not necessary to cut off lateral ocean flow to chill out.

  64. thingadonta says:
    June 28, 2014 at 6:54 pm

    Then I noticed when drawing New Zealand it isn’t aligned N-S, and the reason-well its mostly volcanic. So is Japan. So is Hawaii. So is Indonesia. There must be something going on here. The chances of the majority of continents being aligned nearly N-S is nearly zero, yet they are. I’ve never heard anything about it though.
    —————-

    thingadonta, there is something going on there and it is called …. tectonic plates, volcanoes and the “ring of fire” ……. and a picture is worth 1,000 words ….. so take a lookey-see at this picture graphic, to wit:

    http://www.volcanogallery.com/_borders/RINGOFFIRE.gif

    Tectonic plates are either moving away from one another or over/under one another and volcanic islands form on the boundary between two plates irrespective of their N-S or E-W alignment of said boundary. .

  65. rayvandune says:

    Wait a minute… a new theory? Are theories still allowed in climate science? I figured it would be settled by pronouncements from now on. This could get completely out of control, with people reverting to disprovable hypotheses, observations and archaic behaviors like that. How will our betters tell us what to do then?

  66. thingadonta says:

    Samuel C Cogar,

    thingadonta, there is something going on there and it is called …. tectonic plates, volcanoes and the “ring of fire”

    You mustn’t have read my earlier posts. What is strange is that most continents are aligned N-S (see above discussion, which I won’t repeat). The chances of this occurring at random is close to zero, as evidenced by the fact the volcanic arcs are not aligned N-S.

    Centripetal force?

    The currents that form the plate motions in the crust that originate in the mantle probably aren’t aligned or occurring at random, their actual positions may well be effected by the actual spin of the earth. It seems continent orientations in any case are effected by the spin of the earth.

  67. You mustn’t have read my earlier posts.
    ————-

    thingadonta, you asked a question, ……. I answered it.

    Now I am not going to argue with you about “the odds are” ….. or “the chances of” …. anything happening or not happening in the natural world.

    The FACT is, ….. whatever is, ….. IS. Explaining why …. IS, .. IS, …. is oftentimes controversial.

    Here. thingadonta, , argue with this site, to wit:
    http://www.astro.virginia.edu/class/oconnell/astr1210/guide12.html

    Then skip down to this “heading” of …. E. “Plate Tectonics”

  68. mpainter says:

    Milodonharlani:

    The Oligocene was an ice age, beginning some 33.7 mya. The colder climate started abruptly at its beginning and ended at the next epoch- the Miocene, which was not an ice age but a period of warmth. This all is basic stuff, and the the temp. charts, given per dO18, are on the web.

    As a geologist, I am up on this stuff. That the Isthmus of Panama causes the present Ice Age is unsupported speculation.

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