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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 276 to 300 out of 338:

  1. Sam your comment reminds me of this:

    It is extraordinarily unlikely that ten of thousands of scientists are wrong about global warming. Especially when the Earth continues to accumulate heat, ice continues to melt, and sea level continues to rise as expected. 

  2. sam @275:

    "I also appreciate that there can be this cherry-picking on both sides of an argument and in different ways, when something 'appears' to show something basic, like Ice-accumulation on antarctica, it can be 'viewed' in a different light."

    The way to avoid cherry picking is not to look at yet more anecdotal evidence as you are doing.  It is to look at the summary statistics.  Thus, while you quote incidents from some states in the US, in fact in 2016 to date, there have been 640 warm daily records compared to just 121 cold daily records, a ratio of 5.29 to 1 in favour of the warm records.  Globally, to date, there have been 46,542 warm daily records compared to 8,275 cold daily records, a ratio of 5.64 to 1 in favour of the warm records.

    In contrast to those record, your listing of incidents is 100% cold incidents.  When the data shows >5 to 1 in favour, but all your samples come from the 1 rather than the >5, we know very clearly who is cherry picking.

    Further, this tendency towards of warm records is something which is well known, and increasing in magnitude:

    (Data for contiguous USA, source)

    While this is in fact what you would expect from global warming, the idea that we could have global cooling while warm records outnumber cold records by >5 to 1 is an absurdity.

  3. I do not consider charts such as that,to be reliable.. I saw something on one of the news, "April 2016 was the hottest on record, and it wasn't even close"  This was the same April that was freezing all over the NE and central US with heavy snow..and it wasn't just the USA, east asia and europe were also cold, not as cold but it wasn't very spring like.. There have been April's in my life where Spring actually existed, this wasn't one of them, even May is cold.. How could that possibly be the coldest on record.  Climate Central's chart says one thing, but tony hellar puts up (3)charts, using US HCN stations that there were more days in the 30s, and 60's that were over 90,95,100*  That there were more hot days back then, then there are now.. Charts contradicting each other, ice studies contradicting each other, the charts in the 70,s and 80's showing one thing, the currentcharts showing another..  at this point I only look at weather patterns not charts.. what comes to mind ofcource is all the reliable data we had that showed Iraq had a WMD program..


    [RH] You don't get to merely dismiss data you don't like and accept data you like. You need to show why the data is wrong if you don't accept it. If you're incapable of doing this, then perhaps you should consider the possibility that you don't know what you're talking about and should keep your mind open to the potential that reality may be something other than what you prefer to believe.

  4. sam @278:

    "I do not consider charts such as that,to be reliable."

    Of course you don't.  I never imagined for a second that you are one to let a "beautiful theory" be spoilt be ugly facts.  So you just cherry pick some more.

    First, when discussing the record global warmth, you cherry pick data from the USA (which had only its 18th warmest April).  And not the USA as a whole, but only two particular zones within the US.  You can guess which zones be looking at the temperature rankings by state for April 2016:

    You make a point of mentioning the North East (which was near average, or below average for the 20th century, and hence very cool relative to 21st century to date) and central US (which is a bit of a stretch, given that most states in the central region were above average, and hence below average for the 21st century todate) - but you very carefully do not mention the North West where three states had their second warmest April on record.  I'm sure that was entirely accidental, and not in any way an attempt to cherry pick /sarc.

    You also manage to mention Europe (where parts were near average relative to the 20th century record) - but no mention of Australia, or the central Meditarainian, or the Indian Ocean, or the Amazon, in all of which large tracks were the warmest on record.  Now either you genuinely believe the Globe consists of just the US and Europe, or you are cherry picking.  Outrageiously so.


    I like statistical evidence where you can see at a glance that you are not getting a biased picture.  If you say April 2016 wasn't that warm, but have to restrict your discusion to less than 5% of the globe to make your case (as you have), then you have not case.  You ought to either be honest with yourself about that fact, or leave discussion here to the grownups who are happy to look at the whole of the data, and don't start invoking conspiracy theories every time the data doesn't tell them what they want to hear.

  5. sam @278,

    If you are to get anything from your visits here, it would be best if you show your data sources. I get the impression you are rather too wedded to Tony Heller & his website, a place that is certainly packed full of WMD or Wordage of Mass Deception, so you may be reluctant to do this.

    However, data sources are always useful. For instance, if you track down the Heller post you talk of with its "(3)charts, using US HCN stations" you can also find the source of the drought chart Heller uses, which is an update of Fig 2.3a of U.S. Climate Change Science Program Synthesis and Assessment Product 3.3, June 2008. (PDF here) Note that it was likely sight of Fig 2.3b that gave Heller the inspiration for his post. But tellingly for us here, what else is there in that document of June 2008? I think there is some (for instance, see Fig 2.4) that makes a bit of a nonsense of this talk of yours of cooling US winters.

  6. and i think what people like tony hellar are saying is that these charts include adjusted and fabricated data.  In April I checked the weather for various cities in the US everyday, Boston, Wichita Falls, WDC,NY, everyday it was freezing, like i said there was a white easter and 16 FEET of snow in PA, everyday in the entire region it was freezing or near freezing..if it was 60* in PA then why was there 16 feet of snow, if it was so warm then why was only 5% of the crop planted?  Today is May 20 Chicago-low7*c, high 18, NY 12,21 WDC 12,21 wis 6,22 etc.   according to your chart it was warmer in april than it is now.. obviously the charts that the noaa put out are faked.. i put up photos that showed much more ice in greenland now than just a few years ago, but im sure you have charts that show opposite..

    also tonys charts that shows there are less days now that break 100*f, 95*F than in the 30's and 60's .. real or fake?


    [DB] Inflammatory and sloganeering snipped.

    Please note that posting comments here at SkS is a privilege, not a right.  This privilege can and will be rescinded if the posting individual continues to treat adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Moderating this site is a tiresome chore, particularly when commentators repeatedly submit offensive, off-topic posts or intentionally misleading comments and graphics or simply make things up. We really appreciate people's cooperation in abiding by the Comments Policy, which is largely responsible for the quality of this site.
    Finally, please understand that moderation policies are not open for discussion.  If you find yourself incapable of abiding by these common set of rules that everyone else observes, then a change of venues is in the offing.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter, as no further warnings shall be given.

  7. oh i see, those are not temps they are 'temp. ranks'  this is exactly what im talking about.. they will always manage to slice the data in a way that shows it's 'warm'  again they are saying that April was the warmest april on record.. that's obvious bullshit when it was freezing the whole month with snow and asia and europe were also cold.. I was just watching the Rome masters with djok and murray last week, been watching it for years, this year everyone in the stands were wearing jackets and scarves, i checked the weather it was 11*c there in May.. it has been a very cold april and may..something is being seriously fudged here.


    [DB] Inflammatory and sloganeering snipped. 

    Please see the Moderation advice given you in your previous comment.

  8. Suggested reading for Sam:

    Extraordinary Heat Wave Sweeps Southeast Asia and Points Beyond by Christopher C. Burt , Wunderblog, Weahter Underground, April 19, 2016

  9. Once when I was browsing youtube, less than a year ago (i guess) i came accross a bit like "The Dick Hartman Show" and he said he was going to interview a guest, Michael Mann(im sure you know who he is) and if I remember correctly MM was going to talk about the possibility of an extremly cold period starting around 2020, due to in his opinion, "conveyer belt shutdown" a theory used in the Denis Quaid movie "The Day After Tomorrow"  oddly enough that would be the same time the current weak solar cycle would be bottoming out.. I'm thinking pdo&amo both cold at the same time but i don't know what a 'conveyor belt is' any information anyone has on that theory? seems to be the co2 version of iminent ice age..

  10. later i was unable to find the interview..

  11. Sam,

    When you are unable to find your supposed evidence people here believe that the evidencce never existed.  It appears that you remember a lot of evidence that you cannot now find.  If you want to convince people at this web site you will have to start supporting all your wild claims with citations.  I note that Tom Curtis has provided data and evidence for all his claims, and written citations so they can be verified.  You have provided no evidence to support your wild claims.

  12. i never said i had 'evidence' i said i heard about an interview once about the theory that the movie 'day after tomorrow' was based on.. and that theory is a co2 theory (or man made warming theory), so its one of the 'establishment' science things..since they used it in a hollywood film and hollywood tends lend support to the co2 science..i'm not bent out of shape about the evidence you have posted indicating that warming is continuing.. i know that the skeptic's have questioned the reliability of some of these charts that orgs like the noaa put not going to challenge them here as anyone can goto those sites.. all i did here was to suggest that extreme cold events like super blizzards in the north and snow in the tropics 'seem' to be on the increase and that these are typically 'mini-ice age' conditions and they 'seem'to be gathering pace as the solar minimums set in.. and that possibly the global warming movement was born from the fear of an imminent ice age..  in short I am interested in global cooling and mini-ice age so i asked about any information on the theory that co2 or manmade warming can create a very cold spell.


    [RH] You're clearly not listening to anything that's being said. And you're just prattling along with your incorrect information that you can't seems to find.

    You've been given multiple warnings now. Patience is wearing very very thin. You're going to have to significantly up your game if you want to continue your posting privileges. 

  13. Suggested supplemental reading:

    India just set a new all-time record high temperature — 123.8 degrees by Angela Fritz, Capital Weather Gang, Washington Post May 19, 2016

    ‘99 Percent Chance’ 2016 Will Be Hottest Year by Andrea Thompson, Climate Central, May 18, 2016

  14. sam:

    You wrote:

    ... in short I am interested in global cooling and mini-ice age so i asked about any information on the theory that co2 or manmade warming can create a very cold spell.

    The scientific body of evidence about the impact of increased CO2 levels on the global climate system does not support such a theory. 

    In addition, the surface atmosphere of the earth is but one component of the the global climate system — see the SkS Glossary for details.

  15. Sam @284/7.

    You certainly take the prize for obtuse referencing. A YouTube interview that you once heard about which was about a theory used as the basis for a Hollywood move? The following will likely not help you one bit but for correctness sake...

    The work that led to Michael Mann being interviewed last year is likely Rahmstorf et al (2015) “Exceptional twentieth-century slowdown in Atlantic Ocean over turning circulation.” (Here)

    And a paper that more dramatically considers the impact of melt waters on regional temperatures is the discussion paper Hansen et al (2016) “Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2ºC global warming could be dangerous.” (PDF).

    Do note however that neither fit with your considerations of 'mini-ice age' conditions or solar minimums or frosty US weather.

    The film you mention does apparently have a small role in climate science in that it is the exemplar of “scientific misinformation in movies” that it is said to have prompted Schmidt & Mann to create the website.

  16. Sam: More facts for you to ponder...

    According to the NOAA monthly temperature report (for April), much of Russia and Alaska witnessed temperatures of at least 3.0°C (5.4°F) or greater above average. South America, Africa, and Asia (with an exceptional heatwave in Southeast Asia) also had record high average temperatures.

    The April globally averaged sea surface temperature was 0.80°C (1.44°F) above the 20th century monthly average, the highest on record.

    According to data from NOAA analyzed by the Rutgers Global Snow Lab, the Northern Hemisphere snow cover extent during April was 890,000 square miles below the 1981–2010 average. This was the smallest April Northern Hemisphere snow cover extent in the 50-year period of record.

    April continues record temperature streak, WMO* Press Release, May 20, 2016 

    *World Meteorlogical Organization

  17. I remember reading once that the NOAA doesn't have access to Russia, so they model the climate there?

    Anyways here's the latest on the hottest May ever.. I already assuming that in a few weeks I'll see something in the news declaring May the hottest ever..

    May 16, 2016: 4to7 inches of snow in Maine-record breaking snow for May, New England record spring snowfall 6+ inches, Vermont, PA, Michigan, Ohio 3+ inches, Tennessee US Highways closed because of Ice + snow. This is the first time there has been snow in Maine this late, last time was 1972 but that was may 2nd.. this is past middle of may. Vermont snow record for may broke by 15X.. Ohio snow during this years marathon.. Michigan cities all get snowed,not since may 13, 1912 have they had snow and that was .01 inch.. this time it's 3 inches.. Strange 'snowpellets' in PA, odd type of snow,hail combination not before seen.. Wisconsin cold and snow record broken, 5" Snow in Montana and WY, Waterloo and Dubuque Iowa record cold, Dallas FtWorth record cold.

    NE USA and Canada-glaciated during an ice age-experiences very cold conditions during a min-ice age.. solar minimums are creating the mini-ice age weather pattern..  I think I said this before..AGW or co2 warming does not stop for example, the elnino/lanina weather pattern, ie:it doesn't 'cancel' the lanina so that you get 2 elninos in a row instead of a normal elnino/lanina.  If it can't 'cancell out' a 'little' weather pattern like a lanina, then why would it 'cancell out' a BIG weather pattern like a MIA?  It won't, this thing is coming, it's coming hard and fast and we're looking at serious cold related crop damage from now thru the early 2020's as we get to the bottom of solar cycle 24..we then have somerecovery in the mid 2020's prior to the maunder minimum starting in the 2030's AND with volcanic activity already high we could have a big one like a pinatubo at any time, if/when that happens we're realy screwed!

  18. Yes, Sam @ 292 , and have you noticed that India has recorded a record high temperature in this month of May? A scorching 123.8 degrees Fahrenheit ( 51degreesC ) in north-west India. That is a scorcher indeed - making Maine & Vermont look quite temperate.

    Returning to USA April, the north-west was very much hotter than usual.  And Alaska . . . Alaska showed April as 10.0 degreesF above the 1925-2000 average figure.

    That's ten full degrees hotter, Sam.  Or 5.5 degC if you're scientifically inclined [which I gather you aren't] .  To quote NOAA : "parts of the Yukon River observed the earliest ice break-up on record and Fairbanks observed a record early 'green up', or start of the vegetation growing season.

    Some extra snow in a small part of the USA is looking rather trivial, in comparison.

    Worldwide for April, there was cooler than average weather in the Patagonia region and the Quebec region.  The rest of the world was hotter than average.  Sam, for land area, that's about 99.8% warmer, versus 0.2% cooler.

    Sam, your argument looks ridiculous and a nonsense.

  19. You mentioned SE asia earlier and according to your source, 'on the average, hot record broke, etc.'  I will take your sources with a grain of salt if you don't mind but that's irrelivant.  Mini-ice age conditions like 1816 are characterized by winter conditions that arrive when they are not supposed to be there, like May or September, and it is in that way that they ravage crop production.  You mentioned SE Asia earlier and that there were hot records broke and a high average etc.  But if you look up at my list:

    March 2016: Vietnam had 1 foot of snow 300km south of hanoi.

    This is interesting because March,April is SE asia's summer-it is when the sun is directly over that region, so that is 1 foot of snow-in the summer-in the tropics,deep in the tropics.. Thailand was also hit by that cold spell leaving everyone scratching their heads as to what was going on.

    We do not have an accurate record of exact specific temps from the previous MIA period, we just know from the history books what the weather patterns were.. maybe some records were broke or are these averages or records being influenced by localized heat island effect from human activity..that's your ongoing debate with skeptic scientists- Roy Spencer [ ] or whoever, WUWT people..

    admittedly that debate is beyond me, to study and pik that stuff apart is beyond my comprehension.. admittedly maybe you are right about that but anyone who has looked at this issue even in passing; can see that endless debate; i think its your comfort zone to make that argument; but that's not my argument..  Is it normal to have snow in the middle of May snow in the tropics etc. of cource thats not normal!  since about 2010 those incidents are increasing as the solar minimus preogress.

  20. Sam @ 294 , the "foot of snow 300km south of hanoi [sic]" was something being reported for January 2016 and in the mountains.

    I can't vouch for the accuracy of the reports . . . but you should note that Vietnam is in the Northern Hemisphere where January = winter. Also please note that it is far from unusual to get snow on mountain-tops . . . especially in winter

    Really, Sam, your comments are becoming sillier and sillier.

  21. Sam,

    According the this news article from Vietnam, it was the first time they had snow in that area of Vietnam for 40 years.  Before that it occasionally snowed, it was not close to their record cold.  It has not snowed in the last 40 years because it is warmer from global warming  You are claiming that non-record cold is unusual when cold like this was normal 100 years ago.  cartoon

    I will also point out that most of your claims are of snow, not record cold.  It can snow when it is not record cold.  Since you are interested in the USA, so far this year there have been 23,000 hot records and only 6,000 cold records source.  You have picked some of the minority of cold incidents.

    Your recollection of Russian temperature records is once again false.  Russia provides temperature data to the scientists who track global temperatures.  You are just making things up.


    it may have been early feb instead of march but it was a first ever in that region, there was also a first ever in Taiwan, Kuwait and Guadelup caribian and a few other places.. in February there was a cold that moved into se asia

    I may have gotten the dates wrong it was late january and then middle of Feb, here is some snow in taiwan in Feb.. but in SE Asia its usually very hot already as of late Jan, mid Feb.. and actually in 2011 there was a rare cold condition that left bangkok, all of Thailand and the rest of se asia in March:

  23. Eclectic @295 & Michael Sweet @296.

    There is basically folk out there like this loudmouthed fantasist using YouTube to feed any fool who is willing to listen. His Jan 2016 report is here. His Jan 2015 report of snow 300km NE of Hanoi here. The altitude of these events is likely a requirement of the snowfall. Hanoi has a January climate reported as 19ºC (max) & 15ºC (min) so add 4,000ft @ 3.3ºC drop per 1,000ft and snow in a cold winter is a distinct possibility. I did think to look out an SE Asia temperature record from BEST which show a lot of year-to-year variability but they stop in 2013 so Jan 2015 & 2016 could have been as cold or colder than Jan 2011 which (for minimum temperatures) was the sixth coldest on a record stretching to 1853. (The record cold-min Jan was 1930 with 1963 in second.)

  24. Ooops! I spot @298 that I missed the link to this loudmouthed fantasist which makes my use of a demonstrative pronoun open to alternative interpretation.

  25. Thanks for that info, MA Rodger.

    Sam's ideas and claims are certainly a joke.

    As to Thailand, Sam links us to a blogger in Bangkok [] who goes on to say that April 2016 was "sweltering" [unquote] and seemed like "the hottest year ever" [unquote] .

    It seems clear that Sam doesn't check his sources, and doesn't apply any common sense.  And accepts any second-hand "denier" guff that comes his way.

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