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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)

According to ice cores from Antarctica, the past 400,000 years have been dominated by glacials, also known as ice ages, that last about 100,000. These glacials have been punctuated by interglacials, short warm periods which typically last 11,500 years. Figure 1 below shows how temperatures in Antarctica changed over this period. 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?

Figure 1: Temperature change at Vostok, Antarctica (Petit 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.

To answer this question, it is necessary to understand what has caused the shifts between ice ages and interglacials during this period. The cycle appears to be a response to changes in the Earth’s orbit and tilt, which affect the amount of summer sunlight reaching the northern hemisphere. When this amount declines, the rate of summer melt declines and the ice sheets begin to grow. In turn, this increases the amount of sunlight reflected back into space, increasing (or amplifying) the cooling trend. Eventually a new ice age emerges and lasts for about 100,000 years.

So what are today’s conditions like? Changes in both the orbit and tilt of the Earth do indeed indicate that the Earth should be cooling. However, two reasons explain why an ice age is unlikely:

  1. These two factors, orbit and tilt, are weak and are not acting within the same timescale – they are out of phase by about 10,000 years. This means that their combined effect would probably be too weak to trigger an ice age. You have to go back 430,000 years to find an interglacial with similar conditions, and this interglacial lasted about 30,000 years.
  2. The warming effect from CO2 and other greenhouse gases is greater than the cooling effect expected from natural factors. Without human interference, the Earth’s orbit and tilt, a slight decline in solar output since the 1950s and volcanic activity would have led to global cooling. Yet global temperatures are definitely on the rise.

It can therefore be concluded that with CO2 concentrations set to continue to rise, a return to ice age conditions seems very unlikely. Instead, temperatures are increasing and this increase may come at a considerable cost with few or no benefits.

Basic rebuttal written by Anne-Marie Blackburn


Update August 2015:

Here is a related lecture-video from Denial101x - Making Sense of Climate Science Denial

 

Last updated on 7 August 2015 by MichaelK. View Archives

Printable Version  |  Offline PDF Version  |  Link to this page

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.

Acknowledgements

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:

 

Comments

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Comments 176 to 200 out of 410:

  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 16.2.4.1 "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 1.4.3.4 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: http://www.dailymail.co.uk/news/article-1339149/Big-freeze-Temperatures-plummet-10C-bringing-travel-chaos-Britain.html
  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: http://geodesy.unr.edu/ 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: http://www.landscheidt.info/?q=node/61 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:http://www.john-daly.com/stations/stations.html 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: http://www.2012online.org/2012research/iceage/ For the new little ice age that's emerging now: see this site: mail.google.com/mail/hl=en&shva=1#inbox/12d1de941be48ea3
  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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