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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Are we heading into a new Ice Age?

What the science says...

Select a level... Basic Intermediate

Worry about global warming impacts in the next 100 years, not an ice age in over 10,000 years.

Climate Myth...

We're heading into an ice age

"One day you'll wake up - or you won't wake up, rather - buried beneath nine stories of snow. It's all part of a dependable, predictable cycle, a natural cycle that returns like clockwork every 11,500 years.  And since the last ice age ended almost exactly 11,500 years ago…" (Ice Age Now)

At a glance

In something like a Day after Tomorrow scenario, the idea that a new ice-age was just around the corner was the subject of a book, a DVD and a website created in 2002. The author was a retired architect, by the way. Fortunately for us, both the movie and the quote above are figments of someone's fertile imagination. But let's have a quick look at ice-ages and what makes them tick, after which we hope you will agree that the notion that another ice-age is just around the corner is nonsensical.

Ice-ages, also known as glacials, are cold periods that occur in a cyclic fashion within an Icehouse climate state. Earth's climate has been mostly of the Hothouse type (no Polar ice-sheets). However, on occasion it has cooled down into Icehouse, as has been the case in the last few million years. There are regular variations in Earth's orbit around the Sun, taking place over tens of thousands of years. These affect the amount of Solar radiation reaching our planet. During the Icehouse state, such variations can lower and raise planetary temperature sufficiently to trigger swings between cold glacials – when ice-sheets expand towards the Equator – and mild interglacials – when the ice retreats back polewards.

To give an idea of the time-scales involved, Europe and North America have seen glacials and interglacials come and go repeatedly over the last 2.5 million years, this being known as the Quaternary Period of geological time. The last glacial period started 115,000 years ago and the Last Glacial Maximum (LGM), when the greatest ice extent was reached, was around 22,000 years ago. The current interglacial – also known as the Holocene, commenced 11,700 years ago.

A general pattern may be seen here with a long cooling down towards Glacial Maximum but a relatively quick warming into an interglacial. The speed of the warming-up part of the cycle is due to climate feedbacks. Removal of pale, reflective snow and ice cover revealing the darker ground beneath allows more solar heat energy to be soaked up. Melting of permafrost releases carbon dioxide and methane. These and other feedbacks serve to amplify the warming effect, speeding it up.

However, our burning of fossil fuels has happened on such a vast scale that we have blown such factors apart. The atmospheric concentration of CO2 has risen well above the 180-280 ppm range typical of recent glacial-interglacial cycles. The current level, getting on for 420 ppm, is more typical of the mid-Pliocene. That was a geological epoch that happened around a million years before the start of the Quaternary. Mid-Pliocene ice-sheets were much smaller than those of the present day. Rather than being due another glaciation, we can expect a continued transition towards mid-Pliocene conditions.

Please use this form to provide feedback about this new "At a glance" section, which was updated on May 27, 2023 to improve its readability. Read a more technical version below or dig deeper via the tabs above!

Further details

Because our current interglacial (the Holocene) has already lasted approximately 12,000 years, it has led some to claim that a new ice age is imminent. Is this a valid claim? No.

To explore this topic further, it is necessary to understand what has caused the cyclic shifts between ice ages and interglacials during the Quaternary period (fig. 1). Such shifts are in part a response to regular changes in the Earth’s orbit and tilt, which affect the amount of summer sunlight reaching high northern latitudes and were described by the Milankovitch Cycles, first proposed in the early 20th Century by Serbian mathematician Milutin Milankovi? (1879-1958). For more about Milankovitch cycles this NASA page offers lots of graphics and explanations.

Figure 1: Temperature change through the late Quaternary from the Vostok ice-core, Antarctica (Petit et al. 2000). The timing of warmer interglacials is highlighted in green; our current interglacial, the Holocene, is the one on the far right of the graph.

When incoming sunlight declines in the high north, the rate of summer snow and ice-melt declines and the ice sheets begin to grow. When incoming sunlight increases, the opposite happens. So where are we in these cycles today? Changes in both the orbit and tilt of the Earth do indeed indicate that – were they singularly responsible for climate shifts - the Earth should be slowly cooling. However, recent research shows that is too simple. That's because we now have analyses of ice-cores going back 800,000 years or more. We have devised ways to use stable isotope ratios of various elements in things like fossils and we have developed many other proxy methods for telling us more about conditions in the relatively recent past that the Quaternary represents.

A number of irregularities in glacial-interglacial cycles have been determined, for example times when interglacials were skipped when orbital patterns suggest they should have happened. (Koehler and Van de Wal 2021). Such research has also been aimed at resolving the question of why Earth's 41,000 year obliquity cycle was a strong driver of glacial-interglacial transitions up until around one million years ago. Since then, glacials have instead typically lasted for much longer - around 100,000 years.

The importance of feedbacks within Earth's climate system has been increasingly recognised as the decades have gone by. A good example is the speed of transition from glacial to interglacial, which is relatively rapid because certain very effective climate feedbacks are involved. One such feedback involves albedo, defined as the ability of different bodies to absorb or reflect sunlight (e,g, Thackeray and Fletcher 2016).

Albedo is expressed on a scale of 0 (black body, absorbs everything) to 1 (white body, reflects everything. Fresh snow has a high albedo of as much as 0.9, whereas the muck revealed when old snow and ice cover melts has a much lower one in the range 0.2 to 0.4 – it can absorb lots more solar energy. So melting snow and ice leads to more heat energy retention, amplifying the warming (Fig. 2). 

Albedo Explainer (John Mason)

Fig. 2: Albedo feedback explained. Freshly-fallen snow is highly reflective of incoming sunshine, so that most of the solar energy is simply bounced back towards space. Bare sea ice can potentially absorb about half of the incoming energy, so if conditions become warmer, causing the snow to melt, there’s more energy retained on Earth. If the sea ice melts too, then almost all of the incoming solar energy is absorbed by the much darker surface of the sea. So an initial warming directly results in further warming. Graphic: John Mason.

Another feedback happens when permafrost gets thawed out, since the ground is then able to release previously trapped CO2 and methane. During a glacial, the extent of permafrost is vast, so as it thaws, the release of such gases occurs on an enormous scale – again, amplifying the warming.

Researchers have also modelled ice-sheet dynamics, investigating how the sheets behaved as they melted, for example. It has been found that the shorter-lived, lower latitude Northern Hemisphere ice-sheets that existed prior to one million years ago were much thinner and therefore easier to melt. So ice-sheet dynamics looks to have a role in the much longer freeze-ups of the past million years. This all goes to show that glacial periods arise through a whole lot of factors interacting with one another, of which orbital cycles are but one, albeit important, cog in the gearbox and are not necessarily able to drive the climate system from one state (glacial) to another (interglacial) in total isolation (e.g. Bintanja and Van de Wal 2008; Berends et al. 2021).

Talking of cogs in the gearbox, we are another – and a big one. Our intentional disturbance of carbon reservoir rocks – what we do when we seek, extract and burn the fossil fuels – is unique in the geological record. It's a one-off in the planet's 4.56 billion year long history and while the consequent overloading of atmospheric CO2 levels is still insufficient to take Earth back into a Hothouse state yet, it is perfectly adequate to prevent another glaciation any time soon.

Last updated on 27 May 2023 by John Mason. View Archives

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Argument Feedback

Please use this form to let us know about suggested updates to this rebuttal.

Further reading

Tamino discusses predictions of future solar activity in Solar Cycle 24.


Many thanks to Sami Solanki for his invaluable advice and feedback as well as John Cross for his very helpful comments.

Further viewing

potholer54 published a video tackling this myth on June 27, 2020


Dave Borlace explains why we are not headed towards an ice age in this "Just have a think" video published in December 2019:


Denial101x video


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Comments 176 to 200 out of 411:

  1. muoncounter - I'm just wondering, what do you think my point was?
  2. @NQoA: I think your point is that you're going to disbelieve the science, whatever it says, as long as it does not conform to your preconceived notions about the reality of AGW. "I'm not the one expecting that warming should be linear." Nor is anyone who understands the science, despite what you seem to be insinuating. Stop trying to set up that strawman argument, no one's buying it. "I didn't miss anything, I was pointing out that the AGW team - up until recently, promoted the expectation that the ice sheets and glaciers would continue to recede" They have, when you look at it globally. Of course, when you engage in such cherry-picking as you've demonstrated, that doesn't really matter, does it? Is that what skeptics have been reduced to? I remember when we had quality opponents, such as BP - not amateurs such as NQoA who still try to say it's not warming...
  3. #174: "I'm not the one expecting that warming should be linear." Great! That means you admit there is warming going on, which promotes you out of the 'four legs good, two legs bad' 'no, its not' crowd. "if one presupposes that human activity in some way affects the temperature of the Earth." I'll go out on a limb and guess that you don't. There are many threads that more appropriate; you should look at them and see how well your opinion holds up. I'll continue this comment here.
  4. Re: muoncounter (175) Check out the video I linked in your comment. The Yooper
  5. #179: I would say cool, but somehow that doesn't seem right. Did you notice they have an 'Ice Museum'? As in a place where someday children will go to see pictures of ice?
  6. Re: 180 Right next to the pictures of farmland and skyscrapers...
  7. NQoA writes: "would you be kind enough to send me a couple of links to examples, pre 2005, were the IPCC or friends specifically stated that they expected the sea ice extent to increase, glaciers to increase or record cold temperature to occur post 2005." Wow are you ever dwelling in a fictional reality. How can you look at the frequent up and down short term variations of the data and believe that anyone was ever claiming that would suddenly switch to unidirectional changes... rather than saying that the long term trends would continue to be in the same direction? It's a ridiculous interpretation on its face. That said, there are countless examples of statements about continued variability. Since I don't know exactly who you consider to be 'friends' of the IPCC, let's go directly to the boogeyman in question; "Changes in ice sheets and polar glaciers: Increased melting is expected on Arctic glaciers and the Greenland ice sheet, and they will retreat and thin close to their margins. Most of the Antarctic ice sheet is likely to thicken as a result of increased precipitation." IPCC TAR WG II Chapter 16 overview "Whether the sea ice in the Arctic Ocean will shrink depends on changes in the overall ice and salinity budget, the rate of sea-ice production, the rate of melt, and advection of sea ice into and out of the Arctic Basin. The most important exit route is through Fram Strait (Vinje et al., 1998). The mean annual export of sea ice through Fram Strait was ~2,850 km3 for the period 1990-1996, but there is high interannual variability caused by atmospheric forcing and, to a lesser degree, ice thickness variations." IPCC TAR WG II Chapter "Features of projected changes in extreme weather and climate events in the 21st century include more frequent heat waves, less frequent cold spells (barring so-called singular events)" IPCC TAR WG II Chapter So there are the three specific things you wanted to see from before 2005... all in the IPPC Third Assessment Report released in 2001.
  8. Game, set, match: CBDunkerson.
  9. Coldest December in England's history:
  10. @Tom Loeber: worthless anecdotal evidence. Try again.
  11. #185 First ever recorded summer snow in Australia. Things are starting to get interesting now!
  12. @186 I think you'll find that snow on Mt Wellington is hardly a Christmas novelty.
  13. @kdfv #186 Yes. Summer snow in Australia first ever recorded in: a) 2012 b) 1921 c) 1856 d) 1884 Guess!! (A hint: think about what you need to record summer snow) The Bureau of Meteorology of Australia has information about. For example, a page with recommendation for buildings in the cool temperate region states: "The cool temperate climate has mild to warm summers and cold winters. In the higher parts of the Snowy Mountains, snow can fall at any time of the year. In Tasmania, summer snow has been reported at elevations as low as 300 m." @archiesteel #185 The blunder in Tom Löber's link is announcing that in the middle of December. The same way I'll soon be able to report that last two weeks of December were hot record here in Buenos Aires, possibly some 3 or 4°C above the previous hot record for December. The link in 184 only claimed a similar period to be some tenths of degree below the "previous" record.
  14. @kdfv: November 2010 is the hottest on record. Which is more significant? Summer snow in a La Niña year, or the hottest November in one of the hottest (if not *the* hottest) year?
  15. #188 Are these the only years, because they have a big significance. The first three were a long time ago.
  16. #189 The significance is that the record cold in the uk is happening with vastly increased CO2. This seems to go against the trend.
    Response: Nope. Use the Search field to find the post It's Freaking Cold.
  17. For the future of human kind I hope I am 100% wrong to what follows : 1.The earth , as shape , is not one PERFECT sphere , therefor every minor change of axis would result in a change of the solar radiation absorbed . 2.One such change of 1,5 degrees took place in 2010 . 3.The result was indeed a more vertical positioning of the equator towards the sun which leads to a temperature raise for the sea water in the equators . 4.By that the amounts of vapors has raised together with warm air streams that makes vapor clouds to lift higher so when they are above europe or north america they freeze spontaneusly due to the contact of lower atmospheric temperatures (in the atmosphere higher= colder )giving them heavy snowings we observe lately. As a result of all the above we may consider the ice age has started this winter ,the sky will keep on showering snow untill everything will be covered by it and when I am talking covering I mean 300 metres of ice throughout the northen hemisphere above longitude 40 . This was the short resume of my thoughts on the actuall climate problem.What frightens me the most is the fact that glacial periods apear with a strict periodicity , so the argument of one astronomical event taking place as a regulator of their appearance and disappearance is not to be discussed !!!! And apparently this took place this year .....
    Response: [Daniel Bailey] Please be so kind as to provide linked references for those (ahem) "unusual" claims. Or be taken for a troll-bot. Thanks!
  18. Don't worry. You are one hundred percent wrong. Please read up on Milankovitch cycles and solar variability, and how the increased heat retention from enhancing the greenhouse effect overwhelms it. Do you have a reference for the orbital tilt claim?
  19. There are lots of scientists who study and monitor the shape of the earth. Here is an example: There is no mention by them of any sudden changes in 2010.
  20. #192: Perhaps this is a reference to the Chile earthquake? If so, the numbers are way out of any realm of possibility. Of course, there have been lots of large earthquakes in recent history; no ice age yet. Here's one that explains why such an axis shift did not, nay, cannot happen.
  21. Re: muoncounter (195) Sounds like another variant of Hapgood's crustal displacement mythos.
  22. Hey, those crystals might just align one day. Since you're the one 'in pharmaceuticals', party on, dude!
  23. The historical record indicates that we are now in a repeat Dalton like minimum (called Landscheidt). This is expected to last through solar cycle 25. However, around 2015 or so, its expected that the solar gauss will fall below 1500. Then the sunspots may wink out completely. It is further predicted that a new Maunder like minimum will then begin. So, global cooling has, in fact,begun and will last most likely for the next 70 or 80 years. See this site: Also, I checked the worlds annual mean temperature charts. Not much of a visual upward slant in temperatures everywhere I looked world wide for the last 50 years. The urban site temps were not used as they are unreliable. So upward and downward wiggles appear all but natural variations. Look for yourself and you be the judge! See this site: In Greenland, eight WW2 bombers from the "lost squadron" were found in 1986 under 267 feet of ice. How's that for melting glaciers? I didn't take the rest of the article seriously. See this site: For the new little ice age that's emerging now: see this site:
  24. Henry, Try reading the entry you are replying to, including the intermediate version. The increased heat retention from the enhanced greenhouse effect is an order of magnitude larger than the decreased heat from a return to Maunder minimum levels of solar activity. As for "urban records are unreliable", refer to argument #6 which is linked at the top of the left column.
  25. @Henry: too bad your theory isn's supported by observation, which means it's likely bunk. Oh, and you don't get to choose which temperature records you want to use, and which ones you don't. That's called cherry-picking, and though it might be the contrarian's favorite activity, it doesn't hold much weight in a scientific discussion. The "2012online" site is a joke, while your last link is to a gmail message. Fail. Simply put, there is no indication that a new ice age is emerging. You should spend less time on pseudoscience site and more time reading the articles here. You'll learn a lot.

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