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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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What has global warming done since 1998?

What the science says...

Select a level... Basic Intermediate

Every part of the Earth's climate system has continued warming since 1998, with the ten record temperature years all occurring since 2010.

Climate Myth...

It hasn't warmed since 1998

For the years 1998-2005, temperature did not increase. This period coincides with society's continued pumping of more CO2 into the atmosphere. (Bob Carter)

At a glance

This date-specific talking-point is now something of a historical curiosity, but we'll leave it in the database for now because it's such a good illustration of the simplistic yet reckless mindset of the serial climate change misinformer. And indeed, we could (out of sheer mischief) have revised this myth by replacing "1998" with "2016". In fact, that's what we started to see in the climate change misinformation stream, © the Usual Suspects. But 2023's record temperatures put a stop to that.

Anyway, as first predicted over a century ago, Earth's surface, oceans and atmosphere are all heating up. That's due to our increasing greenhouse gas emissions, but over the years the warming has occurred at varying rates. This should in no way come as a surprise. Other physical phenomena periodically act either to suppress or enhance temperatures.

A prime example of such a phenomenon is the effects of La Nina and El Nino. This natural climatic oscillation features variations in winds and sea surface temperatures over the tropical eastern Pacific Ocean. The cycle can at times strongly influence temperature and rainfall patterns right around the world.

In a La Nina year, temperatures are suppressed, whereas an El Nino year sees them enhanced. This is noise on the long-term upward trend. That's why climatologists work with multiple decades, not just a few years in isolation, in order to get a grasp on what is going on.

The year 1998 featured a massive El Nino. The temperature spike it caused was a huge outlier, like a pinnacle towering over the landscape of the temperature record. In the following years there was a return to more typical conditions, with an erratic but upward warming pattern. That sequence of events gave deniers a brief opportunity to insist that global warming had “paused” or had even stopped.

You only need to remember one thing here. Those who create and spread misinformation about climate change don't care about reality. Public confusion is their aim. In this instance, the misinformation exercise involved deliberately selecting a limited block of years starting with the massive El Nino of 1998 and using that very warm starting-point to insist that global warming had stopped. They knew this would likely work for a few years and that the public would quickly forget why that was the case. Mother Nature had handed them a gift. It was an irresistible bunch of low-hanging fruit to exploit: little wonder the tactic is known as 'cherry-picking'.

Talking about reality, what actually happened? Well, as of 2024, a couple of decades down the line, the top ten warmest years have all been since 2010, whatever observation-based dataset you choose, with eight of them being in the 2015-2023 period. 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, 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

Even if we ignore long term trends (something deniers often do in order to make a point) and just look at the record-breakers, as of early 2024 the top ten warmest years have all been since 2010, whatever dataset you choose, with eight of them being in the 2015-2023 period. In this top ten grouping, 1998 is nowhere to be seen any more. It was not warm enough.

The myth of no warming since 1998 was largely based on the satellite record estimates of the temperature of the atmosphere.  However, as discussed in the video below by Peter Sinclair, even that argument is no longer accurate.  The satellites show warming since 1998 too.

There's also a tendency for some people just to concentrate on atmospheric or surface air temperatures when there are other, more useful, indicators that can give us a better idea how rapidly the world is warming. More than 90% of global warming heat goes into warming the oceans, while less than 3% goes into increasing the atmospheric and surface air temperature.  Records show that the Earth has been warming at a steady rate before and since 1998 and there is no sign of it slowing any time soon (Figure 1). 

Fig 1

Figure 1:  Global Energy Inventory: observed changes in the global energy inventory for 1971–2018 (shaded time series) with component contributions as indicated in the figure legend. Cross-Chapter Box 9.1 Figure 1 (part a) - From IPCC AR6 WGI Chapter 9.

Even if we focus exclusively on global surface temperatures, Cowtan & Way (2013) shows that when we account for temperatures across the entire globe (including the Arctic, which is the part of the planet warming fastest), the global surface warming trend for 1997–2015 is approximately 0.14°C per decade.

Ultimately, every part of the Earth's climate system is warming, and has continued warming since 1998.

Last updated on 8 March 2024 by John Mason. View Archives

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Argument Feedback

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Further reading

Tamino further explores the warming trend since 1998 in Garbage is Forever and Wiggles.

I've kept my original treatment of the subject as other websites hotlink to the images. My original treatment uses similar arguments to Fawcett and Jones 2008 although their analysis is much more rigorous (as you'd expect in a peer-reviewed paper).

Further viewing

Fact brief

Click the thumbnail for the concise fact brief version created in collaboration with Gigafact:

fact brief


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Comments 201 to 225 out of 241:

  1. Peter42, if your basic question is "what would convince me that non-significant or no warming is taking place," then the answer is "non-significant or no warming taking place." If, instead, you're asking about AGW fundamentals, then I'd have to be provided with a comprehensive physical model that did not allow CO2/H20/et al. to absorb and emit within the range at which the sun-warmed surface of the Earth emits, and one which did not allow cooler "objects" to radiate toward warmer "objects." Absent that alternative model, anthropogenic global warming must be taking place. Is some cooling factor countering the warming? Perhaps, but that doesn't mean the GHG factor has stopped doing its thing. If insolation drops and aerosols increase, both providing overwhelming cooling effects, does that mean that AGW is not occurring? No. The warming--or, as some semantic trolls like to have it, "the slowing of cooling"--is still occurring, even when the temperature is trending down. That's what Foster & Rahmstorf (2011) partially addresses. Strip away the major cooling/warming factors (solar, ENSO, volcanic) other than GHG, and what do you have left?
  2. Also missing is the other important question. Given the strong internal variation, what is the shortest time period over which the predicted warming trend could be detected? Estimates are somewhere around 17-20 years unless you strip out some of the known natural variability like Foster and Rahmstorf did. So your statement "According to the latest HadCRUT4 data, there is no statistically significant increase in temperature (0.083C/dec +/-0.172C/dec)" applies to which period exactly?
  3. How does the current "man is causing global warming" theory jive with the facts that the earth has normal cooling (glacial) and warming (interglacial) cycles? According to my research, it is a fact that we went into a interglacial period (global warming) over 11,000 years ago. So, yes we are in global warming and its cause had nothing to do with man's activities because there weren't many humans 11,000 years ago and the humans that were around didn't drive vehicle or have power plants. Interglacial periods, from my research, can last 40,000 years. My take, considering the above facts, is that man's involvement with global warming is insignificant, it's going to happen with or without man, just like the next glacial period will.
  4. michaelcomaha: Your inquiry is off-topic on this post. To point you in the correct direction (both in terms of re-posting your inquiry should you desire and as an answer) please click on the #1 most used climate myth.
  5. michaelcomaha @203, as Composer @204 notes, your inquiry would be more appropriate in the 'climate's changed before' discussion. However, it's worth briefly noting that the planet had been cooling since about 8,000 years ago until about 150 years ago. While there is warming leading into an interglacial, the interglacial periods themselves are relatively stable and generally slightly cooling.
  6. michaelcomaha, I have responded in a more appropriate place.
  7. According to my research...
    Although it's a response to an off-topic comment, it has general applicability so I will note that it seems to be a characteristic of many non-scientists that they think that reading a few unreferenced, out-of-context sources constitutes "research". It doesn't. 'Real' research is a systematic and thorough process that involves assessing both a broad and a representative section of the area being studied, and doing so in a manner that minimises any personal bias input. Research also requires some understanding of the basics underpinning the field being investigated,in order that the data acquired is properly analysed. What michaelcomaha did, as so many other non-scientists do who want to pretend at making a scientific point, was to simply cherry-pick one or two factoids with which to construct the illusion of having a clue, and a point. He has neither, because he did no actual, real research. He simply read some stuff.
  8. 203, michaelcomaha, As others have pointed out, this needs to be discussed elsewhere, but before you go there to pursue the topic further (as I hope you will), one key point... Interglacials can last a long time, but their duration is not random. We well today understand the orbital forcings behind the glacial transitions (not completely, no, there are lots of gaps, but well enough). The fact is that temperatures for the current interglacial peaked about 8,000 years ago, then started to decline, and should still be declining on the way into the next glacial period. So while a cursory glance at glacial periods suggests that you can ignore current warming, a closer and more educated view of the subject suggests that your own argument shows that you should be even more alarmed than you might have been before. Beyond this, it is also virtually certain that we have guaranteed that the Earth will skip the next glacial period, in spite of the orbital forcings. CO2 levels will not fall enough to permit another glacial period to completely occur (I'm not saying that's a bad thing, just that it's true).
  9. Hi, I know that there have been ice ages in the past, and even during the middle ages (mini ice age). I would like to see how the temperature of the earth has increased since the last ice age and whether we are seeing an increase that has been happening for a long time rather than just during the industrial era. I haven't heard anyone explain the global warming that began at the end of the mini ice age in the middle ages. Just to put this in perspective, the sea levels during the last ice age were hundreds of meters below the current level and I see nothing that links those levels with the current levels and the changes is sea levels and temperatures over the long term.
  10. Steve, this post Is sea level rise accelerating? shows an acceleration in sea level rise corresponding to recent CO2-induced warming on top of the ongoing rise since the end of the LIA in the 1800's or so. The explanation of the global warming that ended the LIA is here
  11. Steve at #209:
    I would like to see how the temperature of the earth has increased since the last ice age and whether we are seeing an increase that has been happening for a long time rather than just during the industrial era. I haven't heard anyone explain the global warming that began at the end of the mini ice age in the middle ages.
    If you haven't "seen" anything or "heard" any explanation, then you are simply demonstrating that you are ignorant of the science. There's a whole Interweb out there with which you can UTSE, or you could go through Skeptical Science's own archives to find the relevant commentary.
  12. Steve, I have responded on a more appropriate thread.
  13. Britain's Met Office’s Hadley Centre is said to be reporting that there has been no warming for the past 15 years. What do you make of this?
    Response: That "saying" is incorrect. See the Skeptical Science rebuttal.
  14. Rosco, that is news to me. Can you provide a link to their research that says "that there has been no warming for the past 15 years"? It must be powerful stuff, to overturn the laws of physics and the metrics of ocean heat content.
  15. In section: Is 1998 actually the hottest year on record? you have a link for: A new independent analysis of the HadCRUT record sheds light on this discrepancy ... with the URL of: This URL no longer exists; the new URL is: -scott
  16. "Is 1998 actually the hottest year on record?" In the contiguous US 1998 is the warmest year on record. The trend since then, however, has been down. 2012 is almost certainly to be the "new" warmest year on record in the US. Nevertheless, the 1998 record high annual temperature will have to be broken by almost two full °F for the downward trend to be broken. This seems unlikely. But, who knows, 1917 is the coldest year on record and it was replaced by the warmest in just four years. The average annual temperature went up 3.7°F from 1917 through 1921.
  17. plfreeman? So... what ever happened to plfreeman, who was going to re-analyze your data and come up with better curves?
    Response: [DB] That was the only comment ever placed at SkS by that person.
  18. I just looked at the datafiles from GISS, HadCru 3, RSS, & UAH (yes, you can download them yourself and plug them into a spreadsheet and see for yourself). Since everywhere I turn there is a different version, I needed to check for myself. For the last 15 years (December 1997-November 2012), here are the trends: GISS: +0.1 C/decade HadCru 3: -0.008 C/decade RSS: -0.01 C/decade UAH: +0.05 C/decade So, according to the climate records as of December 2012, warming has stopped for all practical purposes since 1998 (a mean warming trend of 0.02 C/Decade is close enough to 0 that only a zealot would argue the point). I also noticed there is a considerable gap forming between the records, if normalized to January 1980. (-intimations of dishonesty snipped-). (In all fairness, RSS and UAH are very close, HadCru 3 is in between those 2 and GISS, which shows the most warming)

    [DB] You knowingly or unknowingly prosecute a meme. A meme based on a lack of understanding of statistical significance. One detailed in this recent blog post here.

    Furthermore, when applying the Foster and Rahmstorf methodology, the global warming trend in each of the major data sets IS statistically significant since 2000.

    Please read them for enlightenment.

  19. Just read them, thank you. I fear those sorts of articles give the public serious doubts about the science of AGW. (-intimations of impropriety snipped-)

    [DB] Arguing from ignorance and an incomplete understanding of the science, compounded by accusations of impropriety and academic fraud detract from your credibility. If you dispute the content of the linked posts, discuss your concerns there, not here.

    For posts discussing why the PDO is not responsible for the observed warming trend, use the Search function in the upper left portion of any page here for an appropriate place to learn...and then discuss, if need be.

    Again, read the Comments Policy (link adjacent to every Comments Box)...thoroughly. Future comments constructed such as this one will be summarily deleted in their entirety.

  20. Question : I have found on another web site a neat looking plot of temperature versus year going well back in time. It states that this graph is from SKS and consists of 11 different temperature records averaged. If indeed this graph comes from SKS can anyone tell me where to find it here? It would seem that this graph would be on topic for this thread, if indeed that web site was correct. Sorry I cannot be more specific about where I found the graph, I lost those notes. I would keep digging further until I found it again if there is an interest.
  21. The simple fact is there has been a 16-year halt in warming, in stark contrast the the 30 years before that. This though is still short in climate time-scales, and other indicators have *not* stopped moving, eg ocean temperatures, arctic melt, CO2 rising faster than ever. But since the basic mechanism of greenhouse warming is that the atmosphere warms due to CO2 trapping longwave radiation (leading to overall warming), this suggests the warming of the oceans *cannot* be a consequence of greenhouse warming (since the atmosphere is not warming). It must be something else - but what ?
  22. Yawn. Punksta spreads FUD ("halt in warming"? Really???) by ignoring the 97.7% of the land surface/oceans/cryosphere (the oceans and the cryosphere) which, inconvenient to his messaging, indelibly show warming, by drilling down to that which shows the least warming over that period, the land surface. In fact, when applying the Foster and Rahmstorf methodology, the global warming trend in each of the major data sets IS statistically significant since _2000_ (yes, even less than 16 years) • • And even further evidence that the warming continues (topical data: whodathunkit?): • Fun fact skeptics like Punksta hate #1: The oceans have been gaining 2 Hiroshima bombs worth of incremental energy PER SECOND since 1961. Unabated. Specifically, the total heat content change from 1961 to 2011 (50 years) is approximately 21 x 1022 joules. That's about 210000000000000000000000 joules (a joule is 1 watt for 1 second; so a 100 watt light bulb will use 100 joules in 1 second). That's a BIG number but somewhat unreal. So how much energy is this? What could it do? What is it in the real world, where we don't routinely look at numbers that big. That is HOW Big...? This is a rate of heating of 133 Terawatts (or 0.261 Watts/m2). 133 Terrawatts is 2 Hiroshima bombs a second. Continually since 1961. Every. Second. Of. Every. Day. For. 50. Years. The reality is, due to the radiative physics of CO2, there is an energy imbalance in the Earth's energy budget. As a result, the Earth system (land surface, oceans and its cryosphere) is still accumulating energy, unabated. "Skeptics" like to focus on the tiny 2.3% of the system, the surface temperature record, and then further focus on just 2% of that (the United States) in an effort to distract. Essentially, it's a game of "LOOK!!! Something shiny!!!" • • Fun fact skeptics like Punksta hate #2: That El Nino years, La Nina years and even ENSO-neutral years are all rising in temperature over time (warming). • Basically, Punksta is still playing on the Escalator...except he's trying to go Down the Up Escalator. • The world warms; humans are the cause of it. Life sucks for fake-skeptics, as the incontrovertibly inconvenient data and physics are against them. Facts, like tiggers, are wonderful things, for those who have them.
    "I have never made but one prayer to God, a very short one: "O Lord make my enemies ridiculous." And God granted it. ~ Voltaire"
  23. Daniel, You have completely misread my post - I explicitly note that the oceans (a far larger heat-sink) are warming. My point is merely that * greenhouse warming works by warming CO2 in the atmosphere * the atmosphere has stopped warming Therefore, warming of the ocean cannot be due to CO2/atmospheric warming.
  24. Punksta - The oceans absorb shortwave radiation from the sun, and release it out to space at a rate that is to some extent dependent on overturn rates. Over the last 16 years or so we've seen a rather huge El Nino (pushing heat out to the atmosphere, ~0.2°C or so above the general trend) followed by several La Nina's (absorbing energy from the sun more efficiently, cooling the atmosphere ~0.2°C below the general trend). Really - there are no surprises here. The 2-3% of the thermal mass of the climate represented by the atmosphere is showing some noise due to (primarily) variations in ocean overturning, but the 95% or so that are the oceans are still showing warming.
  25. KR, You don't mention rising CO2 - which means you agree it is not implicated in ocean warming ?

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