The Big Chill: How Yosemite Valley and Other Glacial Examples Disprove the Way-Too-Short Biblical Creationist Ice Age
Gregory Paul is an independent polymath researcher including in paleozoology and geology. His technical studies and popular articles have appeared in Scientific American, BioScience, The Anatomical Record, Annals of the Carnegie Museum, Evolutionary Theory, Journal of Vertebrate Paleontology, Journal of Paleontology, Modern Geology, Historical Biology, Paleobiology, Evolutionary Biology, Cretaceous Research, Science, Nature. His work has been covered by the New York Times, Washington Post, Science Friday, Science News, New Scientist, Discover, Reuters. He designed the Tyrannosaurus in Jurassic Park.
This article focuses on a subject that has received not much in the way of consideration, the young earth creationist (YEC) view of the Ice Age that they propose followed the super flood. In this examination I am going to put some emphasis on one of the biggest canyons in these United States. Not the often discussed Grand Canyon – the reasons why that colossal ditch was formed as a classic riverine V-shaped valley over millions of years in rocks up to 1.25 billion years old, rather than suddenly cut by a super flood in short order in post-flood deposits, has been well detailed.
The valley focused on here is Yosemite. Yosemite has received notably little attention in either the anti- or pro- creationist literature. That is both despite, and precisely because, the California canyon poses overwhelming problems that YEC theory lacks practical means of explaining. This article also focuses on the apologetics of the top two creationist organizations, the Institute for Creation Research and, especially, Answers in Genesis headed by the most popular living YEC, Ken Ham.
The Creationist Conspiracy Theory versus the Natural Truth That the role played by the 2.5 year old Quaternary Ice Age is on the side burner of the creation debate is ironic in that it played a critical role in beginning the scientific undermining of scriptural creationism.
Creationists of various flavors believe those who claim that creation could not have occurred without the existence of a transcendent intelligent designer are engaged in a vast conspiracy of spiritual denial. According the YEC’s, the willful rejection of divine creation includes pretending the planet is more than a few thousand years old. The notion is that stubborn resisters to Biblical creation started to concoct a false geological narrative in the late 1700’s going into the 1800’s in which our planet is supposed to be many millions of years old, disproving the inerrancy of the Word of God. This notion then expanded into a vast conspiracy ofcreator deniers that have been pretending the universe is billions of years old and that organisms evolved over much of that time via natural selection.
The historical truth is that the great glaciation was a key to the accidental overturning of Biblical time scales. Largely Christian early geologists who presumed they were going to confirm the work of God began to come across extensive evidence for extreme past glaciations in the form of many valleys that had clearly been formed by big ice flows, but did not have ice flowing in them. And evidence for tremendous continent-spanning ice sheets was showing up. Knowing that ice flows carve and move rock and earth downslope at a literally glacial pace, they began to realize that actual earth history time must have been far longer than undocumented Biblical time, to the extent that the latter was refuted – scientists have not been conspiring to refute scripture, instead nature has naturally refuted the Biblical creation story via objective scientific investigation that the researchers are merely reporting on. That the planet was not meeting YEC-compatible criteria in all aspects, including granitic glacial valleys that obviously took tens to hundreds of thousands of years to be cut, helped force the budding scientific community to abandon Bible-based creation timelines. They had no logical alternative.
The Great American Freeze That incredible amounts of ice recently covered enormous tracts of the northern hemisphere is so well documented that even YEC makes no attempt to deny the reality of an ice age, even though it is not mentioned in scriptures. And this leads to a tremendous problem for YEC: a lack of sufficient time for vast quantities of frozen water to do very much.
In science-based geological reality, the Pleistocene ice age began about 2.5 million years ago, with dozens of repeating cycles (Kohler and Wal, 2020) of glacial periods each lasting tens of thousands of years, each interrupted by markedly shorter, warmer interglacials that last about ten thousand years, we being in the Holocene expression of the latest interglacial. With glaciers forming enormous, kilometers-thick ice shields over much of Eurasia and especially North America, and gargantuan ice fields topping many mountain ranges, for a combined total of some 1.5 to 2 million years, there was plenty of time for those super glaciers to form, erode, move, and gouge out and deposit lots of rock and dirt.
At the height of the glacial maximums, ice sheets and fields covered about a third of the continents (https://www.climate.gov/media/11951). The ice contained so much water transferred from the oceans that the level of the oceans dropped 130 m, over 400 ft. The biggest single ice sheet was northern North America’s Laurentide – for the purposes of this discussion the name is applied to each re-creation of the shield over the ice age – that smothered almost all of Canada and a fair portion of the USA, down to Long Island and over to and across Indiana and Illinois and the upper plains states (https://www.kgs.ku.edu/Publications/PIC/pic28.html). Of course glaciers flow, because thick ice at earthly temperatures is plastic and becomes mobile under the pressure of its own mass. With little or nothing in the way of down-slope force, the flow of continent sized ice sheets is driven largely by the center of the shield being so thick that it pushes out laterally over hundreds to thousands of miles. In the case of the Laurentide its thickness was over 3 km (2 mi) thick in the region of its center, thinning out to 400-650 m (1300-2000 ft) at its edges (USGS; Broad 2018). Because continent spanning ice shields are not flowing down a strongly inclined valley, they move very slowly, about half a meter a year. But because they run for thousands of millennia, any given spot under the shield can experience hundreds of kilometers worth of ice and debris grinding over it during most of the Pleistocene, while any given unit of ice can flow for many hundreds of miles during that time, making long running ice sheets colossal earth movers. To the degree that the multiple Laurentide sheets scoured much of Canada of its soft earth covering, leaving behind the gouged, rocky surface of the Canadian Shield. Much of that dirt and ground up rock ended up in the northern USA where it helped form future farmlands and prominent geographical features such as Long Island, Staten Island, and Cape Cod, which are terminal glacial moraines on a stupendous scale. Those substantial lands would simply not exist but for the fact that the Laurentide shields spent well over a million years moving and dumping vast amounts of stuff, while in the process digging out the basins for the Great Lakes, polishing hard bedrocks, and scattering about big boulders of Canadian rock south of the border called erratics.
The closest thing these days to the Laurentide sheet in size and depth is the Antarctic ice cap. Over the main body of the latter, annual snow fall is about half a foot per year, which qualifies as desert conditions (Casey et al. 2014). Rates of snowfall on such continent-scale, miles-thick ice sheets are inherently low – the air above them is automatically thin and very cold due to high altitude; cold air, especially when thin, cannot hold much water vapor, most of the ice caps are far from marine water sources, and there are no sudden high mountain ranges to wring precipitation on steep upwind slopes. The ratio of snow deposition relative to resulting solid ice thickness ranges from over 10 to 2.5 depending on how fluffy to icy is the snow (Casey et al., 2014; Graham 2018). So if we assume that it took 50,000 years for each iteration of the Laurentide ice shield to reach maximum thickness, then it would have required about half a foot to 2.5 ft (20-80 cm) of snow in a given year, equaling about 2 to 3 in of rain. Not a problem.
The many problems with YEC theory and all that ice start with the events that occurred before their version of the Pleistocene. YEC tries to wave away the great geological ages indicated by radiometric dating by arbitrarily believing that radioactive decay used to occur at rates far higher than they currently are (Vardiman et al. 2005). If so, then the heat released by so much radioactivity cooking along within just a couple thousand years would have melted the surface of the planet, precluding any super flood, ice age, or for that matter our currently pleasantly cool planetary surface, while in the process irradiating all life with lethal doses of radiation (Morton and Murphy 2004; Isaac 2007) – YEC’s dismiss these incompatibilities with the truth of the perfect word of God by promising that they are “confident” these gross violations of the physics of the universe will be solved (Vardiman et al. 2005). Also, modern YEC actually postulates that the continents moved the thousands of miles from their preflood supercontinent positions into their current locations while the flood was occurring! Even the YEC who proposed this impossible geoevent has admitted that the amount of heat released by opening a magmatic Atlantic basin in a fraction of a year while dragging the leading edges of tectonics plates into the mantle at the rate of dozens of miles a day and so forth would unleash enough heat to melt most of the crust and/or “boil away a layer of water 25 km deep over the entire earth” (Morton and Murphy 2004). Aside from steam broiling the life floating in and on top of the floodwaters, the Ark residents included – while making the atmosphere and waters lethally toxic with nasty volcanic gases – this too would prevent a subsequent ice age, and the planet would these days still be too hot to support anything except perhaps some microbial thermophiles.
But even if the planet were not super heated at the end of the flood, there is the problem of too little time for an ice age. According to the often calculated generational genealogy detailed in the Bible, the earth is ~6000 years old. And the flood, according to the leading YEC organization Answers in Genesis, occurred circa 4500 years before present. Using their entirely faith-based Biblical calculation – there being no actual geological scientific data backing it up – in some posts (Snelling and Matthews 2013, AIG 2018) AIG calculates that the ice age got going circa 4250 years ago, and ended around 4000 years. Just after the Babel affair and before the first cities appeared according to their radical, nonhistorical Bible based estimates (cities actually first appeared circa 9500 BP, Mesopotamia arose 5100 BP, and the Pyramids of Giza went up ~4500 BP). But AIG is very inconsistent. According to another calculation driven by the absurdities of a big freeze lasting a quarter millennium, the ice age lasted 700 years, apparently starting in the immediate aftermath of the flood, which would put its end at just 3750 years ago (Oard 2004; 2007a,b); that, of course, increases the serious problems that stem from trying to squeeze in the beginning of post-flood urban civilizations – which AIG acknowledges did not appear until after the ice sheets were gone – into even less than four millennia. So instead of Pleistocene ice for over 2 million years, YEC proposes it was really in existence for just 250 years – about the same age as the USA – to maybe 700.
Starting with the 250-year YEC ice age, allowing for 100 years of melting, to pile up a couple miles worth of ice in 150 years would require 50 to 200 meters (175 to 700) feet of snow – depending on how icy or fluffy the falling snow was – per year over the majority of the Laurentide sheet, an area covering a third to half of Canada. There simply is no location on the planet that can conceivably receive anywhere close to so much snow so fast. It is not possible for cold air to contain and dump that much solidified water at a usually or always freezing location in so little time, least of all when not on the narrow zone mountain upslopes chronically downwind of cold coastal air currents.
The absurdity of postulating that a glacial shield grew to cover about half a continent with thousands of feet of ice and then all melted away in just a few human lifespans is so reckless, that it helps explain why other AIG posts propose a 700 year long ice age, with ice accumulation covering 500 years. In an additional effort to lessen the growth-time problem, the 700 year scenario proposes that the north continental sheets averaged just 700 m (2300 ft) in depth (Oard 2007a,b), a value too low to drop sea level by the well documented 130 m. Aside from being too shallow a value, the key issue is how to pile all the ice at the deepest region which would be about twice as high as the average. Piling up 1000 m (3500 ft) in 500 years would require some 6 to 25 m (20 to 80 ft) of snow from icy to fluffy respectively a year, over millions of square kilometers. Such snowfall rates are seen in the modern world, but only in locations of limited area, where coastal mountains are capturing steady, wet winter winds, such as northern Japan. Presuming that the ice sheet’s core region got to the more geologically correct two miles demands an even more implausible 18 to 75 m (60 to 250 ft) each year.
YEC theory tries to explain this all away with an extremely speculative hypothesis. Oard (2004, 2007) proposes that the post-flood oceans that were still warm from the heating events associated with the flood were evaporating so much water vapor into the atmosphere, while sun blocking volcanic dusts and aerosols from extensive post flood volcanism were making the continents so cold, that incredible rates of ice accumulation occurred on the continents. But to transfer such enormous volumes of water from oceans to continents so fast would have required the northern lands and the air above them staying freezing cold continuously for almost the entire year, while the oceans and air above them remained so steamy warm that the air topping the oceans could absorb and carry all that water vapor, for centuries. But according to Oard, the oceans were merely warm enough for a “pleasant swim” – that’s necessary to avoid killing off most or all marine life, but such is insufficient to pump the needed amounts of water into the atmosphere. Nor were the continent versus marine temperature differentials sustainable. Obviously, the freezing cold and therefore dense continental air would flow via tremendous surface winds in vast quantities out over the balmy oceans, rapidly cooling their surfaces down in alliance with all the suspended volcanics that kept the sun from warming the seas. That would severely suppress water uptake into the air. Meanwhile, all the relatively warm oceanic air back flowing over the continents would partly displace and mix with the cold land air, probably keeping lands at high latitudes too warm for glacier formation at low altitudes, while quickly eliminating the strong temperature ocean-continent differential the YEC hypothesis cannot work without. After all, the surface temperatures of land and sea broadly equalize in just a few months with each change of seasons. For the apparently deeply impractical Oard scenario in which some 45 million cubic kilometers of ocean water (the over 360 million square kilometers of the surface of all oceans times 0.13 kilometers depth) is evaporated from the ocean surfaces and plopped onto the continents as snow in just a few centuries, a rate up to 100,000 cubic kilometers per year, to be taken seriously, its feasibility would need to be supported by sophisticated computer simulations conducted by an objective team of analysts.
The time problem is not only one of accumulation, it is one of movement. If the Laurentide and other northern hemisphere flatland shields lasted just a few hundred years, creeping along at half a meter or so a year they would have flowed a mere few hundred meters! There would have been no scouring of the Canadian Great Shield, no deposition of the super moraines that make up Long Island et al., no glacial polishing of hard rocks, no deposition of glacial erratics hundreds and thousands of miles from their origin, no digging of the basins of the Great Lakes. In order to accomplish those Sisyphean tasks within the YEC timeframe would require that the shield ice magically zip along at a rate of a couple of hundred meters per day, which violates the physics of the universe including gravity.
The Big Valley Praised as an exemplar of western America’s God’s Country by devout, mainstream Christian John Muir, with its U-shaped cross section, hanging valleys, and ice-scoured rock surfaces, Yosemite is the paragon par excellence of a glacial valley. YEC and ICR admit such, and they do not offer alternative scenarios, none being viable. Including a sudden super flood, or earthquakes, the necessary faulting not being on hand. A feature of Yosemite is its exceptionally tough graniteThe rock is both very hard and in the main unfractured, which is why it retains such unparalleled tall, sheer vertical cliffs – in some places such as half dome rearing over 4000 ft above the current valley floor, which itself is fill-in that lies 2000 ft above the glacially carved bottom (Huber 1987; Duhnforth et al. 2010; Anderson 2018). The walls of less resilient glacially cut valleys are prone to more collapsing when the lateral support of the ice melts away. The foundations of the valley began in the late Mesozoic with the formation of deep underground plutons associated with plate tectonics. Being well insulated by overlying terrain, very slow cooling of the pluton allowed the development of the large interlocking hard crystals that form the granites most resistant to fracturing and abrasion. During the late Cenozoic, uplift exposed the Sierra Nevada batholith to erosion. Initially the Merced River cut a V-shaped valley perhaps a couple thousand feet deep. Then the repeat formation of the Sierra Nevada ice field sent glaciers up to 4000 ft deep down the canyon, carving the U-shaped main valley.
The rate at which glaciers cut very hard rock such as granite is known from direct observation of current examples. Glacial erosion occurs because of plucking and/or abrasion. The former, in which the flowing ice breaks off substantial chunks of rock by fracturing of pieces, is the faster means, but regularly occurs only when the rock is not especially hard and/or is heavily fractured. And even such quarrying excavates semi-hard rock at a rate of at most 100 mm/year (Hallett et al. 1996; p. 190 in Benn and Evans 2010). If the rock is very hard and has few or no fractures, then abrasion is predominant or exclusive. When abrasion is the primary means of glacial erosion, the rock exhibits glacial polishing, a distinctive surface texture in which the surface is both grooved in a consistent direction that follows the flow of the ice, and is smoothed to a reflective semi-gloss texture. Because plastic mountain glacial ice (Mohs value 2-4) is far softer than granite (Mohs value 6-7), the ice has has any direct effect on the granite. It is rocks carried along the periphery of the ice that do the majority of the cutting. But even those boulders are not harder than those they are eroding, make up only a small percentage of the glacier edges. And liquid water and micro air pockets lubricate the contact between the glaciers and valley rock, so the erosion rate is very slow, on the order of less than a millimeter to a few millimeters per year (Hallett et al. 1996; Benn and Evans 2010; Wirsig et al. 2016). The short term erosive power of glaciers in hard rock valleys is illusive, not amounting to much on a yearly or even century basis. That is why when matters are going on the slow side they are often referred to being glacial in their pace.
The majority of Yosemite granite is unfractured and about as hard as igneous rock gets. The sheer walls of Yosemite exhibit the glacial polishing that confirms it was cut ever so slowly by abrasion (Duhnforth et al. 2010). Thus, it took hundreds of thousands of years’ worth of river cutting and glacial grinding at a rate of a few millimeters per year to gouge out the 8 square miles worth of granite that forms the 8 mile long, 1 mile wide and deep Yosemite Valley.
In pseudoscientific YEC mythology the Sierra Nevada Batholith formed as a result of the galloping continental drift during the flood. While being uplifted above sea level and/or shortly afterwards, it was fast cooled by underground water conversion into steam – the kind of process that would have helped boil the global flood sea – while the hardening magma that somehow remains solid rather than infiltrated with water-steam channel cavities. In this time pressed scheme the fantastically swift cooling to below 0°C is needed to allow ice to shortly come along and quickly cut the fresh granite. But such rapid cooling would not have allowed the formation of that existing tough, big crystal, fracture free solid rock it is. Instead the batholith would have consisted of finer grained, softer volcanics like those that form when surface lavas rapidly cool (Huber 1987), which is why lavas never form granites. In the YEC scenario there would have been no time for water erosion of the erosion resistant Yosemite material. Instead rock-laced ice would have had to cut through the hard granites by dozens of feet each year to push out the eight square miles down and across in mere centuries, a rate thousands of times faster than observed with contemporary granite valley glaciers, and that like just about everything else concerning YEC violates the physics of the universe we dwell in.
While YEC’s have written at length about their ideas on how the Grand Canyon was recently rapidly formed, as far as I know when it comes to Yosemite the only detailed attempt to deal with the big granite gulley is to explain how the Sierra Nevada glacial field could form in just a hundred years or so (Brewer and Vardiman 2010). Although rapid ice buildup in the coastal high Sierras directly downwind of the Pacific is not as outlandishly impossible as such is in continental interiors, the calculations are a stretch and suffer from the same formation problems noted above. Note that the YEC’s do not try to pass off the formation of the valley to some form of rapid faulting driven by superquakes, there being no evidence for such.
What the YEC’s are abjectly failing to address is how Yosemite granite could have been cut about a mile deep and across in a few hundred years or less when water, solid or liquid, cuts granite extremely slowly. This failure is almost certainly because they cannot devise anything close to an explanation for such a fantastical event that wouldn’t be eye rolling even for YEC’s. In a cynical effort to brush aside the Yosemite difficulty, an AIG PR tract merely alludes to how the “weathering and erosive power of this glacier was immense” (Snelling 2015). The hard fact is that the erosive power of glaciers in tough granite valleys is immense only over immense geological (and non-Biblical) stretches of time.
Science Based Reality Check of Faith Based Genesis Let’s turn the situation around and consider what our planet would be like if it were formed a half-dozen millennia ago, and a planetary flood occurred about 1500 years after that, followed by a quick ice age. This hypothesis would be verified if radiometrics did not produce dates much over 6000 years, or if there were not evidence of significant continental drift, nor of granitic plutons that take long spans to cool. Sediments deposited during the super flood would exhibit a chaotic mix of creatures rather than the layered, increasingly complex pattern predicted by evolution. The Canadian shield would be covered by thick soils, there would not be glacial erratics in northern Ohio, and there would not be super moraines such as Long Island. Water erosion of highlands, whether glacial or liquid, would have had too little time to do much to hard rock. Yosemite and other granitic valleys would not exist, and nothing more than superficial polish veneers would record the short term ice age in and on the tough surfaced highlands. And the universe would be only a few thousand light years across.
The Creationist Credibility Problem That YEC adherents are evading the obvious impossibility of forming famed Yosemite and other resilient rock valleys around the globe in a few hundred years helps expose the pseudoscientific depth of their methods. Their hypocritical tactics of not telling their followers of the many major logic gaps inherent to their unscientific beliefs – including the field trips they hold at Yosemite – are similar to those who promote the new belief in ancient aliens founding human civilization. The latter creation myth according to surveys, may have become more popular than the declining belief in YEC, as have the existence of bigfoot, psychic powers, astrology, the Loch Ness monster, and Elvis being alive.
Some YEC’s, seeing the super inanity of trying to compress all of universal planetary and human history into six millennia, allow that earth might be tens of millennia old. Although this alleviates the time compression problems a little, it still does not allow enough time to allow glaciers to sculpt Yosemite Valley, much less large portions of continents. At the same time, breaking the 6000-year Biblical temporal barrier denies the perfection of scripture’s divine author, rendering the fundamentalist YEC program moot.
YEC’s must convincingly directly explain every critical point raised herein – piling up vast ice sheets in mere centuries including sustaining for that time the dramatic continent/marine temperature differential, having the Laurentide shield move much of Canada into the USA in that time piling up Long Island et al., cooling the Yosemite pluton into very hard granite in decades and cutting it a mile deep in mere centuries, and so forth. This includes producing advanced computer simulations verifying the YEC speculations. Otherwise it is religion-based pseudoscience mixed with conspiracy theory.
Using Yosemite for Science Promotion While Yosemite in a never ending migraine headache for creationism so toxic to the cause that they ignore it as much as they can, it is a whopping yet oddly underutilized tool for science education that goes untapped. The Grand Canyon has been the premiere super sized chasm for presenting deep geotime to the public, but YEC’s think they can explain it away. In public educational terms, beloved Yosemite is the most readily understandable example (and least subject to seeming refutation) of how a giant canyon could not have been formed in the few hundreds or even thousands of years that the faith-based YEC movement demands that all must believe. It should be at the leading edge of rational outreach as a go-to, user-friendly example of how it took soft ice hundreds of millennia to dig out tough granite a mile deep and wide, firmly disproving the Genesis timeline. This may help accelerate the decline in creationist opinion and Biblical literalism already underway in the USA (Newport 2022; Brenan 2024).
References
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Brenan, M. 2014. Majority still credits God for humankind, but not creationism. Gallup. https://news.gallup.com/poll/647594/majority-credits-god-humankind-not-creationism.aspx.
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Broad, W. 2018. How the ice age shaped New York. The New York Times 6/5. https://www.nytimes.com/2018/06/05/science/how-the-ice-age-shaped-new-york.html.
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Isaac, R. 2007. Assessing the RATE project. Perspectives on Science & Christian Faith June: 143-146. eleted them all by hand.
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