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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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Global cooling - Is global warming still happening?

What the science says...

Select a level... Basic Intermediate

All the indicators show that global warming is still happening.

Climate Myth...

It's cooling

"In fact global warming has stopped and a cooling is beginning. No climate model has predicted a cooling of the Earth – quite the contrary. And this means that the projections of future climate are unreliable." (source: Henrik Svensmark)

At a glance

Earth's surface, oceans and atmosphere are all warming due to our greenhouse gas emissions, but at different rates. Some places are also warming much faster than others: parts of the Arctic for example. That variability is partly because other phenomena act to offset or enhance warming at times. A good example are the effects of La Nina and El Nino, an irregular variation in winds and sea surface temperatures over the tropical eastern Pacific Ocean that can influence temperatures and rainfall patterns right around the world.

El Nino causes even warmer years whereas La Nina tends to peg temperatures back to an extent. Thus 2023 – an El Nino year - was the warmest year on record, according to the USA-based National Oceanic and Atmospheric Administration, but other recent years have not been far behind – 2016 and 2019 are in second and third place respectively. The worrying thing is that 2019 only saw a mild El Nino. And even with a La Nina featuring, 2021 and 2022 were, respectively, still the seventh and sixth hottest years on record.

The year 1998 featured a massive El Nino and consequent temperature spike that was a strong outlier, well above the steady upward trend. That spike and the subsequent return to a more “normal” warming pattern led to claims in the popular media that global warming had “paused” or had even stopped. This was a typical misinformation tactic that, as usual, time has proved wrong. As things currently stand, the top ten warmest years have all been since 2010 and 1998 is nowhere to be seen any more. By modern standards, it simply wasn't warm enough.

Please use this form to provide feedback about this new "At a glance" section. Read a more technical version below or dig deeper via the tabs above!

Further details

In the years following 1998, at the time the hottest year on record, there was a concerted misinformation campaign to convince the public that global warming had variously slowed down, stopped or even that we were entering a period of cooling. Of course, we now know that such claims were nowhere near correct. In today's top ten ranking of warmest years, the year 1998 is nowhere to be seen. It simply wasn't warm enough. So let's take a look at how the claims came about, because they reveal insights into the methodology of those who design and spread misinformation.

The entire planet continues to accumulate heat due to the energy imbalance created through our greenhouse gas emissions. Earth's atmosphere is warming. Oceans are accumulating energy. Land absorbs energy and ice absorbs heat to melt. Year to year ups and downs in these things are simply noise, reflecting variations in how that heat is moved around the planet and what other influences are at work, such as the irregular El Nino Southern Oscillation (ENSO) that can nudge the global temperature one way or another by up to 0.3C. That's why 1998 was such a warm outlier: it coincided with a very strong El Nino. El Nino conditions always warm things up whereas La Nina conditions cool things down (figure 1).

GISTEMP-ENSO-coded-plot from RealClimate

Figure 1: GISTEMP anomalies to end-2023 (with respect to late 19th Century), coded for ENSO state in the early spring - red is El Nino, blue La Nina. 2023 is in grey because that El Nino did not develop until later in the year. Graphic courtesy of Realclimate.

Climatologists routinely use multi-decadal blocks of time when presenting temperature trends for a very good reason. Such blocks allow you to stand back and look at the bigger picture. Due to the noise, taking a much shorter time-span – say just five or ten years – allows you to say anything you like about trends, depending on the particular block you pick.

For example, if you picked a short run of 5-10 years ending in 1998, you could have – if you were so inclined – said, “look how fast it's warming!” Likewise, taking a number of years starting with 1998, you could have made the equally invalid claim that global warming had stopped. And of course, that claim was made, vociferously, in the early-mid 2000s. It was a classic example of cherry-picking: the manifestly unscientific practice of choosing the data that supports the argument one is paid to make on behalf of those who sponsor misinformation campaigns. Once you know about such tricks, you can challenge them yourself. You can ask someone why they showed such a short temperature record when showing a much longer one is the normal practice.

It is difficult but technically possible to filter out the noise described above from temperature datasets. In the paper Foster and Rahmstorf (2011) the authors used the statistical technique of multiple linear regression to filter out the effects of ENSO, solar and volcanic activity (Figure 2). They found that the underlying global surface and lower atmosphere warming trends have in fact remained steady in recent years. There's still noise in there but nowhere near as much. We were still warming all along.

before/after filtering

Figure 2: Five datasets of global surface temperature and lower troposphere temperature are shown before and after removing the short-term effects of the El Niño Southern Oscillation (ENSO), solar variability, and volcanic aerosols.  A 12-month running average was applied to each dataset.

Last updated on 4 June 2024 by John Mason. View Archives

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On 21 January 2012, 'the skeptic argument' was revised to correct a minor formatting error.

Denial101x video

Here is a related video lecture from Denial101x - Making sense of climate science denial


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Comments 126 to 150 out of 338:

  1. JMurphy 'So far the sceptics seem to be more open''Do you have any examples you can give and link to' Prof Bob Carter James Cook University, Queensland. He has strong views on the subject that are worth listening to. From there you can search for many others. All come from different angles but unfortunatly if they dare to question global warming, even if they agree its happening they are labeled deniers. As far as cranks are concerned I have views and I will leave you to judge others.
    Response: Type "Bob Carter" without the quote marks into the Search field at the top left of this page.
  2. DSL 'Climate science is receiving greater scrutiny than perhaps any other area of science' I hope so and so it should. True enquiring minds welcome scrutiny. However, whenever I see people defending global warming and especially mans influence on it, I fail to see reasoned defensive debate. Personal attacks and labeling them as deniers only stiffels debate.
  3. Notsure (#127) This entire website is a "reasoned defensive debate" of the science behind AGW.
  4. 127 Notsure, Its being defended because the full body of evidence supports AGW. Conversely, there are no supported studies demonstrating otherwise. Contrary to popular skeptic belief, natural causes are not being ignored. Please read the post on Is there a scientific consensus on global warming?
  5. Muoncounter 'There is a huge difference between reflection and absorption/re-emission. Clouds, ice/snow, atmospheric dust, etc reflect a portion of the sun's energy back into space; this energy is then not available to heat the planet. On the other hand, energy that is absorbed at the earth's surface, to be re-emitted as infrared as the surface warms, is at the heart of greenhouse warming.' Warming occurs when more heat is received than lost. Cooling occurs when more heat is lost than received. Whatever mechanism is involved is not important with respect to the question, 'Is global warming still happening?' To me all that is important is to understand which way the heat is moving? When that is known then look into detail. Man made global warming is a recent happening, (over the last 50-100 years?) All the debate that I have seen so far revolves around the data for the last century. I look to the global warming supporters to prove that what has happened over the last century is unatural. So far it has not been shown convincingly to me that anything that has occured climate wise is outside the normal range of climate change either in rate of change or degree of change. I have not found any convincing argument or evidence that increasing CO2 levels do not cause warming. I hear debate on its degree of influence. I am not an expert and I am not qualified to point to any particular paper or theory. But I am entitled to try to understand and question. DSL 'Yet who do you trust? Climate scientists, who don't really roll in the dough and don't have a vested interest in a warming planet (other than having to live in it)? Or pundits and big oil-financed lobbyists whose interests are not scientific but simply in achieving legislative or political effects, whatever the means?' Its easy to acuse to put people on the defensive. I wonder if the big bad oil companies you refer to would really be happy if the global warming threat was removed. I suspect they do quite well out of the publics concern.
  6. Notsure (#130) "So far it has not been shown convincingly to me that anything that has occured climate wise is outside the normal range of climate change either in rate of change or degree of change." How about the 'why' of change? Climate scientists have a pretty good idea what caused previous climactic changes (orbit and solar output) but when those causes are used to explain current trends they fail to completely describe what is observed. GHGs do explain it. If there are other explanations then everyone would be glad to hear about it but so far no other answer has been found that explains the current observed trend. Saying it is natural only works if you can explain what natural event is behind it. I fear this has gone off topic though.
  7. Notsure - I would encourage you to look at the science, look at the data. On this site there are some excellent references to some of your primary issues on the threads Evidence for global warming and The human fingerprint in global warming. This includes plenty of links to papers, data, and many items that point out (a) it's warming significantly over and above natural variations and cycles, and (b) we are responsible for it. Please read through these, and comment on specific issues you might see with them on those threads where it's appropriate.
  8. Ice age alarmists and global warming alarmists have the same aim, simply to alarm. This winter in the the USA has caused damage. It is weather not climate change. The global warming alarmists have diverted attention away from this type of weather. The climate has always changed, look back at history. Climate will always change. It is very dangerous to be complacent and assume we know where the climate is going. The alarmists will always point to any current weather event and imply its some kind of unatural occurence or some local record. Weather will turn up in its various guises the danger is to assume that it will only take one form. Look at what has happened to Australia. Did the global warming alarmists cause the authorities to forget the past floods. Was there assurances that flooding risk in that area was no more? That is a danger that we should all avoid. Alarmists, whether iceage or global warming are dangerous. Nature has a way of reminding us that we are not as in control as we like to think we a
    Response: (Daniel Bailey] Not sure if I can make any difference here, but in case you are actually not of closed mind then read this. You have been given good advice from many others here: demonstrate you are here for the right reasons.
  9. Notsure - I hate to say this, but you are beginning to give the appearance of a Concern Troll. See the Climate's changed before thread, along with CO2 is not the only driver of climate - the climate has changed before, but we actually have a pretty good idea of how and why. Currently, extra CO2 forcings are the dominant (not the only) forcing in effect, causing the climate to warm rather than slowly cool over the last half century. From what I have seen of your postings, you are repeating some very well known skeptic myths and misconceptions, not looking at the large list of Skeptic Arguments discussing those, and failing to follow up on any of the links folks have presented to you as explanations as to why those skeptic arguments don't hold up. You certainly do not act like someone honestly in search of information. I may be wrong about that; I would enjoy being proven incorrect - by seeing you actually looking at and digesting some of the information you have been presented with.
  10. Notsure, unfortunately you seem to be posting a stream of beliefs and opinions without any attempt at trying to back up those beliefs and opinions. Why are you ignoring all the information you have been provided with via this website ? Where are you getting your information from ? Until you start to show where your beliefs and opinions are coming from, they will be treated as unfounded and not credible.
  11. Notsure, The tone of your posts has become increasingly aggressive and arrogantly dimissive. Not only have you failed to discuss any specific objection to current understanding of climate science, you have rudely refused to follow up on any of the links provided for you by these good people in their desire to help educate you. You have also repeatedly labelled them as "alarmists" trying to "divert attention", essentially slapping the hand away each time one is extended to you. Please show some civility, and maybe even a little class.
  12. Notsure : This web site is an amazing resource for the non-scientist to get a grasp of what the science says about AGW. I say that as a non-scientist myself. If you are truly interested in the facts please avail yourself of the information here. When you do you will realize (as KR pointed out) that your concerns and doubts have been discussed here ad nauseum.
  13. #130: "Whatever mechanism is involved is not important with respect to the question, 'Is global warming still happening?'" The question to ask is not 'is global warming still happening?' -- that's been answered numerous times on SkS with a resounding yes. The mechanism is extremely important, if you want to understand what's going on -- which may lead to an understanding of what to do about it. But it appears that you've already got your mind made up, 'notsure'. "it has not been shown convincingly to me that anything that has occured climate wise is outside the normal range ... ." Have you looked at the relevant posts? Considering you seem to be in a position to learn a lot, it's very sad that you aren't willing to try. #133: "alarmists have the same aim, simply to alarm." That's just nonsense. If you want to have any credibility: substantiate, don't declare.
  14. Yup. Still happening: Yes, Virginia, Polar Amplification is Real: The Yooper
  15. Climategate U-turn No warming in 15 years, from the mouth of Phil Jones himself - NEXT!
  16. 140 Mr Anderson. I think you will find that you are completely wrong. Next you should read this and if you have anynew, and interesting data or comments, add them in the comment section. HTH.
  17. 140 Mr Anderson Also read Your welcome.
  18. @139 Why are we looking at a snapshot of the Arctic in 2011 and comparing it to a thirty year range of the Antarctic from 30 years ago to prove that the globe is warming?
  19. You do realise that what models predict is arctic warming but only very slow warming in Antarctica (with some parts getting colder)? Its model verification. Nonetheless, as papers show (even skeptic darling O'Donnell), Antarctica is also warming, and with net loss of ice.
  20. A quick question for all you ladies and gents with far more knowledge than myself. January and February of this year (2011) show a combined land and ocean temperature that is cooler than the past few years. I know that two months is much too short to make claims about trends, but I am just wondering why that might be. I am about to teach a unit on Climate Change and like to give updated temperature information to my students. I foresee this being a question I get from my students and I want to be prepared. Thanks
  21. Re: chudiburg (145) That depends. As you note, it's too short to make any meaningful comparisons. Over a short distance, say 30 feet, a human can outrun a champion quarterhorse. Over a half-mile...not so much. Comparing temperature trends from short intervals is similar. Apples & oranges. Like comparing the weather from the last 2 days to that of the last 2 years. Sure, you can do it, but what's the point? We had the 17th-warmest combined land+sea temps in February in the instrumental record. That doesn't seem particularly cold, does it? And it wasn't hot everywhere nor cold everywhere. Here's January, normal reference baseline: Here's January, last 30 years baseline (just the lifetime of your students): Yeah, it was colder in the NH where most of the people live, but that would be ignoring the rest of the world that was warming. Scientists are concerned with the long-term trend, which is up. That doesn't mean that every month is of necessity warmer than the previous. Weather, like bodily functions, happens. But over longer periods of time, it shows definite trends (let's also remove cyclical stuff like oscillations [which do not add or subtract energy from the system] and volcanoes): That's why climate scientists use 30 years or more of cumulative weather trends to make their studies of climate. Because any trends emerge from the noisy datasets. Too short of a period of time, like a month or too, will typically contain too much noise in the data for any background signal to be seen. Like asking your students how much they grew yesterday, last week, last month, etc. Eventually any growth trend will be revealed. [ Edit: As a footnote, GISS typically updates its online data in mid-month for the previous month, which is why the above graphics only have January data. February should be available at any time soon, here. In Climate Science, "The trend's the thing" (apologies to the Bard). End Edit- ] Hope this helps, The Yooper
  22. chudiburg - Further to Daniel Bailey's excellent explanation: We are in the midst of a strong La Nina event, a lot of the heat from the atmosphere is disappearing down into the oceans. See NOAA sea surface temperature map below: This is part of an ongoing warm/cool oscillation of the climate that has been going on for millenia (at least). It's part of the "natural variability" that climate scientists often refer to. The only way heat can leave Earth is via radiation at the top of the atmosphere. ENSO events (El Nino & La Nina) just shuffle the heat around between the ocean and atmosphere. See discussion here: Global warming and the El Niño Southern Oscillation There's no expectation that each year will be warmer than the previous one, but over longer time-frames we expect the atmosphere and oceans to warm as more heat is trapped by greenhouse gases. Therefore we should see the continual warming show up in long-term records. This is what we see when all temperature records are combined into one graph. Hope this helps too.
  23. Nice summary, Rob! Some February info from Hansen: The Yooper
  24. Thanks guys. I must have missed that we are in the midst of a la nina year. That explains some of the temporary cooling (compared to the last few years at least) I also liked the analogy about how much you grow in a day vs. a week/month/year. Keep up the good fight gentlemen. Cheers!
    Response: [DB] Cheers to you, too. BTW, Feb data is now available from the GISS link I provided earlier.
  25. Anyone in need of a laugh must read this CP analysis of the latest wackiness in Watt$ land: Seals predict cooling! Canadian Harp Seals may have “read” the predictions of the coming decades of stabilization of global temperatures and perhaps some cooling. Animals like the Harp Seal have experienced many millions of years of climatic change and, through the complex processes of evolution and natural selection, may have developed an ability to sense coming changes.

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