Bad Geology Movies: Ice Age: Continental Drift, 2012

Ice Age: Continental Drift


Ray Romano, Denis Leary, John Leguizamo, and a whole bunch of others.

Premise: Can a sudden split of continents and iceberg-sailing pirates separate a mammoth family?Continue reading “Bad Geology Movies: Ice Age: Continental Drift, 2012”

My first crush

National Blog Posting Month – February 2013 – Love

Prompt – Tell us about your first crush.

I’ve had a lot of crushes in my life. Some with people I actually knew, and some with celebrities. I haven’t really outgrown crushes. I still have them. The difference is now I know them for what they are and can generally move on from them relatively rapidly – or at least keep them from continuously occupying my entire consciousness.

I think the first time I had a crush on a boy that was the same age as me was in middle school. There may have been a boy or two that I liked in elementary school, too, but I’m not sure those were full-blown crushes.

But my first *real* crush was on a celebrity. Complete, head-over-heels crushiness. No. Actually, it wasn’t a celebrity. It was a character in a movie (played by an actor who I still find attractive, actually, though not to the level of ‘crush’ these days). Who was it?

Indiana Jones

Indiana Jones

I read the book, then saw the movie, Indiana Jones and the Temple of Doom, when I was maybe in 5th grade. I know I was in elementary school. Boy howdy! Did I think Indiana Jones was one fine human being. I would weave elaborate tales with him and me going off and having adventures together. I bought a bull whip. I yearned for a fedora. I had a length of thick wire that was a stand in for a whip, because I couldn’t figure out how to make the real one work like Indy did. I would play Indiana Jones all the time.

It’s funny that now, as an adult, I recognize that Temple of Doom was probably the worst of the Indiana Jones movies (we don’t talk at all about Kingdom of the Crystal Skull, however. *gag*). Raiders of the Lost Ark, when it was new, was far too much for me. It terrified me. Today I quite enjoy it, though it still look away when everyone melts there at the end. The Last Crusade was an excellent movie, and by the time it came out, I was old enough to appreciate it as such. By then, my crush was over, replaced by one on a school-mate of mine. *sigh*

Be it for better or worse, I have not yet ‘outgrown’ crushes, despite being much older and married to a decent and loving fellow. I guess that feeling of wanting to be swept off my feet hasn’t gone away. But with a few years of experience, at least I know the typical outcome of crushes and know better than to expect anything to come from them.

They’re called crushes because they’ll never actually happen, at least not the way you want them to, so your heart gets crushed. Either you’ll never actually meet the person you’re crushing on (in the case of celebrities), or you do meet them and they turn out to be nothing like you imagined. Crushes are best left alone. They can be fun, but nothing to base your future on.

For 2-4-13

Beware of Movies! Fossils and Paleontology

The Beware of Movies! series is meant to point out some of the scientific inaccuracies of popular movies, specifically in points related to the geological sciences.

This post will point out the major inaccuracies portrayed in movies about the science of paleontology. I’m a paleontologist. This oughtta be good…

Commonly, about two seconds after I tell someone I’m a vertebrate paleontologist, they ask me what I think of Jurassic Park. Then I laugh. It’s either that or they ask me if I carry a whip like Indiana Jones. Then I snarl something about how 1) Dr. Jones was an archaeologist and 2) Indiana was the dog!

Continue reading “Beware of Movies! Fossils and Paleontology”

Bad Geology Movies: Caveman, 1981



Ringo Starr, Dennis Quaid, Barbara Bach

Premise: Could the awkward defeat the hulking in one zillion BC?

Caveman has got to be one of my all-time favorite movies. I liked it when I was a kid, because it was just plain silly. As I got older, I liked it because it had Ringo Starr in it (I was a Beatles fan – I guess I still am!). As an adult, I’m entertained by the subtext. (Zug-zug!) And as a paleontologist, I am wildly entertained by all the inaccuracies.

It’s comedy, so of course it’s fraught with inaccuracy. A lot of it is intentionally blatant. That’s what makes it funny. Because this movie is billed as comedy, any intelligent person knows better than to believe anything in it. I’ll just point out the paleontological silliness and warn you that if you haven’t seen this movie before, there are lots of spoilers ahead!

It opens with a big guffaw. One zillion B.C. it reads on the screen. Zillion isn’t even a proper number, but it is certainly much larger than a billion, thus exceeds the known age of the Earth (even back in 1981).

Setting— Everything about where the movie was shot, down to the tar pits, says California. Well, cavemen were not kicking around in California. They were in Europe.

Dinosaurs and humans— What were they even doing there? Dinosaurs and humans never co-existed. They missed each other by at least 60 million years.

The Dinosaurs themselves— Only two dinosaurs were depicted. One was a lizard-y guy with spikes on his back and tail and a big pointy horn. This guy also had chameleon-like eyes that moved around this way and that. He also had a sprawling stance (his legs out to the side like an alligator). This was clearly made up. This could be a take on the original interpretation of Iguanodon, but I think it was just made up for the sake of the show.

The original (now known to be inaccurate) reconstruction of Iguanodon – Photo by mugly on Flickr

The other dinosaur was Tyrannosaurus rex (I assume). This version of T. rex is a nod to the original interpretation of the dinosaur, with the body held vertically and the massive tail resting on the ground. This is in marked contrast with the interpretation of T. rex in Jurassic park, which itself is totally different from modern depictions of the beast. These days, T. rex is seen as a fleet-footed predator that held its body horizontally and its tail straight out behind. The modern view of T. rex also includes feathers.

The Tyrannosaurus of Caveman is a talented dinosaur, however, able to emulate howling wolves, crowing roosters, and hooting owls. It’s actually worth a bit of a chuckle to think that the crowing and hooting aren’t so far off from possible, given that modern birds are thought to be the closest living relatives to dinosaurs, especially theropods like T. rex.

The pterosaur and the giant egg— Pterosaurs and humans never co-existed either. Though not dinosaurs, pterosaurs lived during the same time and went extinct at the same time as dinosaurs. The giant egg was clearly too large to have been laid by the pterosaur that we see flying around in the movie, but it sure lends itself to a hilarious sequence of events.

A nearby ice age…— This is hilarious because we know it ain’t possible. An ‘ice age’ is a time period, not a place, and certainly, no-one is going to walk from the desert to a frozen wasteland in one day. Nevertheless, the snow beast is adorable and you just have to feel for him. Maybe he was just trying to make friends.

My favorite part of this movie has nothing to do with paleontology. I love the bit where Atouk’s little tossed together tribe has an impromptu fireside music, song, and dance fest. It just makes me happy.

Bad Geology Movies: Dinosaur, 2000



D.B. Sweeney, Julianna Margulies and Samuel E. Wright

Premise: What would happen if a dinosaur was raised by lemurs?

OK. This is totally a kids’ movie. I won’t say anything about talking dinosaurs. And I know there has to be tons of artistic license. Fine. Nevertheless, there are some things about this movie that are terribly inaccurate.

But I only took two pages of notes, and, admittedly, the pencil was blunt and there were pictures. So there’s not too much.

Dinosaurs that I recognized: Iguanodon (e-K), Carnotaurus (l-K), An Oviraptor (Rinchenia) (l-K), Velociraptor (l-K), Brachiosaurus (l-J), Styracosaurus (l-K), Ankylosaurus (l-K), Parasaurolophus (l-K), Struthiomimus (l-K)

Those funny little parenthetical bits there denote the age of rocks in which each of these animals are typically found. (l-K) means the late Cretaceous, just before the dinosaurs went extinct. Luckily, most of the animals depicted in the movie are from the late Cretaceous. That makes sense. The whole movie begins with an asteroid impact which, presumably, represents the one that killed off the dinosaurs at the end of the Cretaceous.

There are a couple of problems though. For one, the main character is an Iguanodon. Iguanodon lived in the early Cretaceous (e-K). That could be 50-70 million years before the rest of the characters. But if that’s not bad enough, Brachiosaurus is from the late Jurassic (l-J), which is tens of millions of years older than that.

So, these animals never actually co-existed.

Lemurs, or any modern primate did not appear on the Earth until at least ten million years after the dinosaurs went extinct. So that just wouldn’t happen. But fuzzy animals with goofy personalities are great for the show.

There are some other bits that were worrysome: Why are the lemurs on an island separated from the mainland? Why aren’t there dinosaurs on that island? How come the nesting grounds are unaffected by the meteor impact? Why are all the dinosaurs essentially sentient, except for the poor ankylosaur?

That landslide was a little sketchy, too. Where did that rock come from?

Oh, and hey. Why did any dinosaurs survive? After all, didn’t the asteroid wipe them out at the end of the Cretaceous? In the end, this is actually OK. Maybe some relict populations did survive beyond the end of the Cretaceous, but died out soon thereafter. There’s even some evidence that this occurred, though most paleontologists are skeptical. The point is that it is plausible that not everything died immediately after the impact.

Besides, it’s a kids’ movie. What do you want?

Bad Geology Movies: Jurassic Park, 1993

Jurassic Park


Sam Neill, Laura Dern and Jeff Goldblum

Premise: What if we could clone dinosaurs and made a theme park around them?

You were probably waiting for this one. I had to do Jurassic Park. I’m a paleontologist. It’s a rule, right?

When Jurassic Park came out, I was in my fourth year as an undergraduate (I’d been a senior for a while already, and wouldn’t graduate for at least one more year), studying both geology and biology. I was going to be a vertebrate paleontologist, and I was pretty sure I was going to study dinosaurs. (I never have studied dinosaurs, but I did become a vertebrate paleontologist. 50% is pretty good, right?)

I never did see this in the theater. I saw it a year later when it came out on video. I watched it the evening of the day that I took the GRE exams. Yes, exams in the plural. This is back when there were only two dates a year you could take the GRE and it was a hand-written test. I took both the general and the subject exam in one day. I was fried that night. I remember laughing at the cute dinosaurs while my roomates and friends fell on me in terror.

Since then, this movie has been a popular one to watch with the various geology clubs I’ve been associated with. It’s full of problems with both paleontology and biology. I’ll try to stick to the paleontology problems.

The bottom line is this: We’re probably not EVER going to see cloned dinosaurs. Now, maybe we can do some genetic engineering and get dinosaur-like animals from modern birds, but that’s about it.

I’m only planning to review the first Jurassic Park movie. The others are based upon accepting the assumptions from the first, so there’s little point in considering the others (with the possible exception of the character Robert Burke, from the second movie, The Lost World).


PORTRAYAL OF PALEONTOLOGY: Oh, goodness, it’s wrong. Just wrong. The setting, the outcrops, were all right, but what the science looked like is wrong.

Exposing the fossil: 1) I have never been to a fossil locality where a brush was all that was needed to expose a fossil. Additionally, paleontologists tend NOT to expose fossils as they dig. They only uncover enough so that they can determine the exent of the the fossil. Then they trench around the specimen, keeping as much rock as possible in place. Once a trench is dug, and the fossil is still encased in rock but now sitting on a pedestal, paleontologists will jacket the fossil with plaster and take it into a laboratory to fully remove it from the rock. Never, never, never do we do such detailed preparation in the field. The specimens will be ruined, if not by people walking on them (or helicopters landing nearby), but by the elements. It takes time, sometimes years, to get a fossil out of the ground. The more that remains encased in rock, the better.

Seismic: Not that I fully understand how seismic works, but I’m certain that a single shotgun blast isn’t going to yield an image by which a paleontologist can recognize the half-moon shape of the dinosaur’s wrist bone.

The fossil itself: Y’know, sometimes a complete fossil is found in its death pose, but usually even then some of the bones are out of place. To find as single complete specimen is unusual. To find two, both laid out perfectly, is so unlikely that I could not suspend reality to accept that part of the movie. And something as big as the ‘Velociraptor’ that they portray would almost certainly have damage or distortion somewhere.

Science and funding: Apparently Hammond, the creator of Jurassic Park, has been providing Drs. Grant and Sadler with $50,000 a year to fund their research. That might seem like a lot of money to you, but in reality, that’s chump change. Just saying. Research efforts like those are expensive, especially if Sadler and Grant are getting any salary from it. I’ve submitted some ‘cheap’ grant requests for less than $50,000 per year. That covers my research expenses and only two months of my salary. Most programs need much more than that.


THE DINOSAURS: They did pretty good with the dinosaurs, all things considered. I’m glad that Spielberg isn’t going to go all “George Lucas” on these movies and fix them up though…

Velociraptors and the relationship with birds: What Alan Grant in the movie says about the relationship between birds and dinosaurs is mostly true. Most of us in the paleontological community refer to birds as ‘avian dinosaurs.’ We have chickens and I am always calling them my little dinosaurs. What Dr. Grant says about ‘raptor’ meaning ‘bird’ may also be true, but let’s face it, that’s not evidence that birds and dinosaurs are related. If I start calling a donut a banana, does that make the donut fruit? No. (Besides, ‘raptor’ actually means ‘thief’!)

Speaking of Velociraptors: The true ‘Velociraptor’ is a little animal that would stand about hip-high on most adult people. The veolociraptors in the movie were enlarged to make them look cooler. When Spielberg came up with this, paleontologists said, ‘Well, ok. Sure. It’s a movie. Go ahead,’ basically accepting that this was going to be wrong. But at about the time that the movie came out, a huge new species related to Velociraptor was discovered in Utah, and was named Utahraptor. The velociraptors of the movie could be Utahraptors in real life. And the paleontology community breathed a collective sigh.

Inferences about behavior: Velociraptors hunt in packs. Gallimimus ran in herds. This is arm-waving. This is literary license. This is not something that can be inferred directly from the fossil record. We don’t know exactly how these animals interacted. We don’t know how they behaved. We can observe modern birds and assume that dinosaurs might have behaved in similar ways. Nothing more.

Inferences about perception in dinosaurs: Apparently, Tyrannosaurus can’t see you unless you move. Dr. Grant knew this somehow. OK, we don’t actually know this. There are animals that can only see objects if they move quickly, like some frogs, but we can’t possibly know if this is true with dinosaurs. By the same token, we don’t know if velociraptors can stare you down, either. If we’re going to base this inference on their nearest living relatives, however, I’m pretty sure that T. rex could see you even if you were sitting still.

Modern understanding of dinosaurs: If this movie were to be made today, the velociraptors would most likely be completely covered with feathers. The T. Rex would also have feathers, probably. Any of the theropods would be feathered. Now, I’m not sure about the sauropods – the big Brachiosaurus – I’m sure someone else knows.

By the way, Dilophosaurus: Dilophosaurus does not have the neck frill that is shown in the movie, and it didn’t spit poison, either.


Cloning: So this is biology, and a bit of chemistry. 1) DNA wouldn’t last. Over 65 million years it would degrade so much that it would be unrecognizable. 2) Frog DNA? If they were clever, they’d use bird DNA. Seriously, a FROG?! Now if we really wanted dinosaurs, what we need to do is study the anatomy of dinosaurs and compare that with birds as adults and embryonically. Then let’s try to make the embryo of modern birds develop to make a dinosaur-like skeleton and see what we get… This, I think, is within the realm of possibility, but the ‘dinosaur’ we’d get won’t be any dinosaur that ever walked the Earth!


Females turning male: Actually, such things are possible. In many vertebrates, the temperature of the eggs during development will determine the sex of the young when they’re born. Equally possible, though not mentioned, is parthenogenesis, wherein a female simply gives birth or lays eggs without fertilization. The babies are clones of the mother. This is known in many species of lizards. It’s a stretch, but it’s possible.


I could go on. There are several little details in the movie that I found annoying, but these are the big ones (or so I think). I’ve got other movies to watch and review…

Bad Geology Movies: 2012, 2009



John Cusack, Chiwetel Ejiofor, Amanda Peet, Oliver Platt, Thandie Newton, Danny Glover, and Woody Harrelson


Premise: What if the end of the Mayan calendar on December 21, 2012 really did mark the end of the world? Could we save ourselves?

Obviously, the world did not end on December 21. The Mayans (modern ones) probably had a good chuckle at the premise of this movie and all the hubbub about the apocalypse. Whatever. In this movie there were some wierd things going on, things that didn’t make sense even within the context of the distorted science of the movie itself. Yeah, it was a disaster movie. A scientific nightmare.

The end of the world has been brought on by excess activity in the sun. Actually, it’s kind of funny because the world will end when the sun finally consumes the planet. But we got a few billion years before we need to worry about that. Anyway, apparently the sun’s activity has brought about a new kind of nuclear particle – a different kind of neutrino that is rapidly heating the Earth’s core, rather like how a microwave heats food from the inside out. This is going to cause the cataclysmic destruction of the Earth as we know it.

Of course, all this is happening because of the alignment of the planets that only happens every 640 thousand years. But wait. 640 thousand years is pretty frequent. Why is there no geologic evidence for this happening? There’s the ‘Nemesis Star,’ but that’s, what, every 26 million years or something? Yeah, I don’t know…

These enormous cracks begin to form along the west coast of North America. But they aren’t due to the action of any tectonic plates (according to one of the characters, the Deputy Geologist of the Office of Science and Technology Policy – which apparently actually exists). Ok, well if it’s not plate tectonic, why aren’t there random cracks elsewhere?

There’s a scene where they’re drilling (or so it seems) into a suddenly-dry lake bed in Yellowstone National Park. Our deputy geologist finds out that the temperature is 2700 degrees C at 40,000 feet deep. First, any real geologist would use meters, not feet. It’s about 12,000 meters or about 12 kilometers. I wonder how long they’d been drilling there. That’s just a gripe. But let’s put this in context. How hot is 2700 degrees C?

The Earth’s geothermal gradient (temperature with depth) compared with the solidus for rocks. If the geotherm is to the left of the solidus, the rocks are not melted.

So we’re looking at mantle temperatures. Not molten rock, mind you. The mantle is solid, but very, very hot. So, under Yellowstone it’s really warm. Well, Yellowstone is also sitting on top of a hotspot, where heat from the mantle (and associated volcanics) make it right to the surface. That’s why Yellowstone is there in the first place. So maybe 2700C isn’t so unexpected?

The other part of the story is that apparently the temperature is increasing by 0.5% every hour in this well at Yellowstone. Well, that’s pretty quick. A few hundred degrees a day or so. That’s substantial. I’d be more worried about that than the absolute temperature.

I guess this phenomenon is occurring at other sites around the Earth as well (in the movie, that is). I wish I knew where. The temperature anomaly at Yellowstone is compelling, but again, it’s a hot spot. It’ll go off again eventually, and we don’t need über-nutrinos to do that. What if the other places on the globe where they’ve been taking measurements are also hot spots. What then?

Regardless, the claim is suddenly made that “The Earth’s crust is destabilizing!” whatever that means, because the “Temperature’s rising with incredible velocity!” Is that even English? Would acceleration be a better word? Can you even use velocity to describe temperature change?

The good news is that crazy Charlie (played by Woody Harrelson) is drinking PBR, which is widely acceptable to geologists globally, for no real clear reason.

Oh yeah, and so you know, there was no major planetary alignment on December 21, 2012. This was just kind of made up…

The Theory of ‘Earth Crust Displacement’ is a big deal in this movie. The idea is that the crust destabilizes (whatever that means) and suddenly the crust rapidly moves around on the earth’s surface. It’s tough to be sure what they mean by this in the movie, as they could be referring to a movement of the crust, or a shift of the Earth’s rotation axis, so that the crust has appeared to have moved relative to the rotation axis. This depends upon a destabilization of the ‘subterranean’ crust and an ‘extreme polar instability.’ I have no idea what these things might mean.

The subterranean crust could be anywhere from just below the surface to 70 kilometers down, so what part are they talking about? Also consider that in the Theory of Plate Tectonics, it’s not just the crust that moves. A real geoscientist would be referring to the lithosphere, which is the crust plus a bit of the underlying mantle. So what’s destabilizing? Maybe it’s the connection between the crust and the mantle that’s destabilized? Wow.

The Theory of Plate Tectonics, does a nice job of explaining how the crust and the rest of the lithosphere, moves about on the surface of the Earth. But the crust isn’t going to rotate 23 degrees to the southwest over the course of a few hours. Sorry folks. Earth Crust Displacement is not a real theory in the Earth Sciences.

So far as ‘extreme polar instability,’ I think this is in reference to the Earth’s magnetic field (the north and south poles), though I can’t be certain. They do discuss the sudden reversal of the Earth’s magnetic field, and that the south magnetic pole is suddenly in Wisconsin. That the Earth’s magnetic field might reverse itself is no big deal. Geoscience has known about this for a while. The magnetic field has gone back and forth many times over the aeons, in an irregular pattern. This pattern has been used to help assign ages to ancient rocks, in fact, in a field of study called magneostratigraphy. That it would happen over night is a little sketchy. The current state of understanding is that it would take at least a thousand years for this to occur, though we’re still working on the details of how the magnetic field is generated. The magnetic pole in Wisconsin is also no big thing, if you’ve rotated all the Earth’s crust by 23 degrees to the southwest. So this is Ok. Sort of.

Earthquakes: This movie suffers from some of the problems of other earthquake movies in that it implies that earthquakes of magnitudes like 10.9 are even possible. Of course, if we can have Earth Crust Displacement, we can have such huge earthquakes, too.

The tsunamis throughout the movie are a real (scientific) disaster. For one thing, just because there’s an earthquake, doesn’t mean that there’s automatically a tsunami. The tectonic situation has to be correct. There needs to be dip-slip displacement along a fault that is underwater. They have these waves arising *poof* out of nowhere!

The other problem is that a 1500 meter tall wave (which is huge, sure) isn’t going to affect a Tibetan monk living at 4000 meters elevation. Unless, of course, Earth Crust Displacement has made the Tibetan Plateau sink. At this point, you see that things only make sense when you suspend all understanding of the current state of science.

Finally, I just gotta say that once again this movie omits the fact that volcanic ash is, by itself,deadly. Movies always portray ash as soft and fluffy and falling like snow. It’s glass folks. They’re inhaling glass shards. And no one is coughing. Sigh.

Bad Geology Movies: The Day After Tomorrow, 2004

The Day After Tomorrow


Dennis Quaid, Jake Gyllenhaal

Premise: When the world’s ocean circulation patterns are disrupted by melt water due to global warming, the Earth is plunged into a sudden ice age.

There’s a fair amount of good in this movie, and a fair amount of hoo-hah as well. I’ll focus on the Earth Science problems that I have at least a little expertice in. I’m not a meteorologist, so I can’t say a lot about the huge storms that play an enormous role in the movie (though I suspect they fall into the category or hoo-hah).

Ice core drilling: This is, in fact, a common means by which we have learned a great deal about Earth’s past climate. And we can go back ten thousand years quite easily. The ice-coring set-up that they have is quite unlike any I’ve ever seen, and I really don’t think any intelligent scientist would be coring on an ice shelf, but for the sake of a movie… ok.

A two-century long ice age that started 10,000 years ago: There was a substantial climate change that occurred ten thousand years ago. It was warming, though, not an ice age that lasted 200 years. This was about the time that humans found themselves in North America and was also about the same time that all the cool ‘megafauna’ went extinct (like mammoths, mastodons, woolly rhinos, ground sloths, etc.) There is a great deal of debate over whether it was the appearance of humans or this climate change that did in the megafauna.

Greenhouse gasses from ice cores: This is actually a commonly used research track by paleoclimatologists. In fact, we have two such scientists in our tiny department here at the University of Rochester. Atmospheric gasses are trapped in snow which is later buried and turns to ice in the massive glacial sheets of the Arctic and Antarctic. These gasses can be retrieved and studied, providing information about past concentrations of greenhouse gasses in the atmosphere.

By the way, we can assign ages to different parts of ice cores by simply counting annual rings. During the winter, snow tends to be clean, but in the summer there tends to be a lot of dust in the snow. Each year, then, there is a layer of clean ice and dirty ice in an ice core. We can count these (like tree rings) to know the age of a part of an ice core. Pretty cool, eh?

Ocean circulations: What the main character says about the disruption of ocean currents by the introduction of fresh water (from melting ice sheets), which then leads to climate change is actually an accepted hypothesis. It has been put forward by Wally Broeker, one of the most respected paleooceanographers in the world.

Unfortunately, the movie does make a mistake here. Not a severe one, but I’m sure Wally himself would facepalm. They talk about the North Atlantic Current – which is a real thing – being shut down by all the meltwater. The North Atlantic Current is a surface current in the ocean. It is the continuation of the Gulf Stream, which runs north along the eastern margin of North America. The Gulf Stream plus the North Atlantic current is what keeps the climate of Europe so pleasant despite being so far to the North. Surface currents, like the North Atlantic Current, are driven by wind.

If you look at the drawings that the main character of the film is referring to, as well as Wally Broeker’s work, you’ll realize that the currents that would be disrupted by the freshwater are not surface currents at all. While it might affect the North Atlantic Current, the influx of meltwater would more likely disrupt the deep ocean currents, called “Thermohaline Circulation.”  These currents are driven by differences in temperature (Thermo-) and salt-content (haline) of the water. Saltier water sinks, as does colder water. This global circulation keeps the ocean water mixed from north to south and from ocean to ocean. An influx of freshwater from melting glaciers in the north and south would stop the downwelling in those areas, which would disrupt this circulation. This, it is widely accepted, could have a profound effect on global climate.

The ocean’s deep currents.

Water inundating New York City: This is a head-scratcher. Sure, if sea-level rises, then water could rush into the city. And now, post Hurricane Sandy, we know that water can make it quite a ways into the city. There is a lot of water tied up in the world’s ice sheets, too, so an immense sea level rise is not out of the question if we melted all of the ice. But the converse is true, too. In an ice age, sea level can drop because all the Earth’s water is tied up in ice sheets at the poles. Somehow, I suspect that these two competing phenomena would have prevented the great wall of water that struck New York in the movie. But it was pretty cool to have a massive ship floating in front of the library, eh?

Only storms in the Northern Hemisphere: Was anyone bothered by this? Why wouldn’t there be enormous storms in the Southern Hemisphere too? How come Australia gets out Scot-free? This actually might not be that big of a problem. It seems that the great ice ages did not affect the Southern Hemisphere in the same way as the Northern Hemisphere. There were no huge ice sheets in the south. Part of this is because there really isn’t much land mass in the south. There are some tall mountains that even now have glaciers that may have expanded during the northern ice ages, but it seems that “ice ages” as we think of them were a primarily northern phenomenon. There’s active research on that topic going on right now. So it’s possible that a new ice age might only affect the Northern Hemisphere.

 An ice age in a week? I think this is fundamentally the biggest problem with “The Day After Tomorrow.” The premise is ok, and the idea that run-away greenhouse gasses could cause major climate disruptions isn’t that far off, but that an ice age can begin and coat much of the Northern Hemisphere in ice in less than a week is a unlikely. Years is a better scenario, and we’d probably have a little warning. Can can observe the flow of the thermohaline currents. We’d see them stopping most likely. Alas, I don’t think that there’s a thing in the world we could do to re-start the flow should it stop. Climatic disruption is the most likely outcome.