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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 2015 shattering temperature records.

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) revise this myth by replacing "1998" with "2016" - and in a few years time, by "2023" or "2024". In fact, that's what we are now starting to see in the climate change misinformation stream, © the Usual Suspects. 

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'. More recently, given that 2016 was the hottest on record, a similar opportunity has been spotted by some misinformers, although it’s not really caught on yet.

Talking about reality, what actually happened? Well, as of 2023, a couple of decades down the line, the top ten warmest years have all been since 2000, whatever observation-based dataset you choose, with eight of them being in the 2015-2022 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 2023 the top ten warmest years have all been since 2000, whatever dataset you choose, with eight of them being in the 2015-2022 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 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 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

Comments

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Comments 26 to 50 out of 415:

  1. Sorry, also using ten year moving averges looks a bit like trying too hard. 12 month averages would seem to be appropriate for a ten year period. S
  2. thewags The far north has a couple of geologoc features that never seem to be talked about. The midatlantic ridge does not stop in the north atlantic but continues on under the Arctic ice pack. A paper last year stated that the activity had increased and that the ridge was spreading faster. The subduction zones are along the northern faces of Greenland to Alaska. So naturally the northernmost zones are showing increased volcanism. With all this increased tectonic activity I would expect major climate change at the north polar region. I truely can't understand why the IPCC has not taken this into account.
  3. It has been cooling for ~8 yrs. Plotting a 11-y moving average conveniently allows you to ignore the last ~6 yr. Plotting a trailing 2-5 y average would catch the recent trend, which correlates with solar activity and most definitely does not correlate with the continuing increase in CO2. This website allows you to explore trends
    Response: There has been cooling over the past few years. However, the surface temperature record is a noisy signal - imposed upon the long term warming trend is much short term variability. Consequently, it's not uncommon for there to be short periods of cooling over the past 35 years of warming.
  4. @Den siste mohikanen who is scaring children, or keeping anyone in poverty? first of all, the only thing we should be able to agree on, is that virtually nothing has been done so far to actually slow down climate change. for every Prius added to the road (which still runs entirely on fossil fuel), there's another new SUV. we've been talking about this issue, but doing virtually nothing. where are the scared children? the younger generation is growing up with the same over-consumption habits as the older generations. and who is "kept in poverty" by climate change science? an analysis of the recent proposed climate bill (going through the US house of reps) is that it would cost the average US family (not person) $175/yr by 2020. how does that amount keep anyone in poverty? who is going to be "kept in poverty" if we do nothing are the poorest countries in the world, that already struggle to find enough water, and grow enough food, to meet demand. it's those countries that will be hardest hit by higher temperatures, not the cooler, wealthier northern powers. they'll be kept in poverty by those who refuse to act on climate change. not the other way around. please don't twist the argument to make it seem like the skeptics are the ones standing up for the poor.
  5. Since the year 2000, atmospheric carbon dioxide has increased 18.4% of the increase from 1800 to 2000. According to the average of the five reporting agencies, the trend of average global temperatures since 1998 shows no increase and from 2002 through 2008 the trend shows a DECREASE of 1.8°C/century. This SEPARATION (there have been many others) corroborates the lack of connection between atmospheric carbon dioxide increase and average global temperature. I wonder how wide the separation will need to get before the IPCC and a lot of others are forced to realize that maybe they missed something. As the atmospheric carbon dioxide level continues to increase and the average global temperature doesn’t it is becoming more and more apparent that many Climate Scientists have made an egregious mistake and a whole lot of people have been misled.
  6. Based on the data and graphs shown on this website ...www.climate4you.com ( under the section " Global temperatures" ) there appears to have been little or no global warming since about 2003. Observations based on the various graphs show according to my "eyeballed" interpretation : University of Alabama data - No warming since 2003. RSS - No warming since 2003 Hadcrut3 - No warming since 2003 NCDC - no warming since 2003 GISS - no warming since 2003 The temperature data on these graphs show a flat or declining trend from 2003 to the present. By "flat" I mean varying within less than say 0.05 of a degree from 2003 to 2007, which I would argue is well within the accuracy with which we can measure the global temperature of the Earth. Also bearing in mind that we are supposedly talking about and looking for the IPCC"s "catastrophic" global warming trend here. After 2007, the global temperatures as shown on these graphs seem to decline more abruptly. Now my questions are: does anyone disagree with the data and trends shown on these graphs ? Does anyone disagree with my observations - and why ? I note also that the graph posted above ( figure 2 ) also shows a flat temperature trend since 2002.
  7. I suggest that the fill-in color areas under the lines in the total heat-content graph be removed. As experts in the graphic display of quantitative information often point out, such filling-in encourages the reader to compare the magnitudes of the areas under the curves rather than the actual graphed quantities -- giving an impression of a difference between the two quantities (in this case) that is roughly proportional to the square of the actual difference. In other words, the fill-in colors amount to inadvertent exaggeration (technically, they encourage ambiguity about whether one is comparing the curves or their integrals). Why give denialist critics even the slightest toe-hold? Simplify the graph. Trust people to get it without the big splashes of color.
  8. FYI: the Murphy 2009 link right under the total-heat graph isn't working . . .
  9. Eyeballing the graphs it seems the gradients for each ENSO adjusted graph between 1910 -1944 and 1964-2005 are remarkably similar. I would have expected the gradient to be related to the concentration of GG's and thus increase more in later years??
    Response: Keep in mind that CO2 is not the only driver of climate - other factors like rising solar levels and a drop in volcanic activity had a part in early 20th Century warming.
  10. I haven't seen reference to the effect of heat of vaporization on the temperature of the oceans. Has this been done and, if so, what were the findings. It seems that since the Heat of Vaporization for water is 3.76 times greater than Heat of Fusion I would expect to see this factored in if melting the ice formations is.
  11. Tim228, i guess you refer to fig.1. The paper from which it is taken is an observational study, they measured the actual heat content of the oceans. Consequently the latent heat of evaporation of sea water as well as all the other energy related effects are automatically included.
  12. John, I am fully on board with the argument that most of the heat is stored in the ocean, and that the atmosphere has a noisy temperature signal. However what I do not understand is the sharp drops in total energy content, for example around 1968 and 1996. Given constant or slowly rising CO2 concentration and the coean heat reservoir with a large time constant, I would have expected (naively perhaps) some monotonously rising function for total heat content. Have any explanations been proposed?
  13. Actually, Mizimi, when you graph the numbers, & draw a trendline, you see the rate of change for 1910-1944 was +0.013 degrees per year, wheras the rate of change for 1964-2005 was +0.016 degrees per year. So this 2nd warming period has been faster than the first one-even though average solar activity during the 2nd warming period has remained unchanged.
  14. Mizimi & others seem to not understand the concept of the Energy Balance. Average Global Mean temperatures for all of 2000-2009 is +0.512, which is a full +0.18 degrees greater than the period of 1990-1999. This is in spite of the fact that the 1990's were dominated by rising sunspot numbers, wheras the current decade has been dominated by record low sunspot numbers (0 for almost the entirety of 2005-2009). Not only that, but the data shows that the rate of warming-per decade-is *accelerating*, not *decelerating*. Lastly, its all very well saying that Global Mean Temperatures will *only* rise by about 2 degrees over the next century (assuming no accelerating in the warming trend), but that is a GLOBAL MEAN. Actual temperature differentiations will be *much*, *much* higher at different parts of the year & at different points of the planet. Winter temperatures might only increase by an average of +0.1 to +0.5 degrees, wheras summer temperatures might increase by an average of 3 to 4 degrees-or more. Some parts of the globe may see a much sharper increase in mean temperatures-& see an increase in heat related disasters. Australia has had 3 record heat waves in the space of only a year, what can they expect in 10 to 20 years time? Also, I'd like to remind you that at least 2 civilizations were wiped out due to a total increase in global mean temperatures of only +0.6 degrees-over the space of almost 600 years. Tell the Anasazi & the Khmer Empire how unimpressed you are by a *mere* 1.8 degree increase in global mean temperatures over the next 100 years, Mizimi. Oh, thats right, you CAN'T because they got wiped out! Seriously, try quoting science instead of regurgitating fossil-fuel industry propaganda, I might then start taking you a little more seriously.
  15. Ocean temperature has decreased since 2003. See R.A. Pielke, Sr., Physics Today, 94, Nov. (2008). which contains this graph: LINK

    Response:

    Actually, the oceans have been warming since 2003. Observations of upper ocean heat show some short term cooling but measurements to greater depths (down to 2000 metres) show a steady warming trend:



    However, the ocean cooling myth does seem to be widespread so I'll shortly update this page to clarify the issue.

  16. In reply to the above ocean comment, doesn't the fact that measurements conflict depending on depth cast doubt on whether or not the oceans are warming or cooling?
    Response: No, it shows that the upper ocean exchanges heat with the deeper ocean, leading to more variability in the upper ocean but a steadier trend in the overall ocean.
  17. Look at this link for information on global warming stagnation since 2002: LINK The site is run by Ole Humlum, Professor of Physical Geography at the Department of Geosciences, University of Oslo. He says that "all five global temperature estimates presently show stagnation, at least since 2002. There has been no increase in global air temperature since 1998, which was affected by the oceanographic El Niño event. This does not exclude the possibility that global temperatures will begin to increase again later. On the other hand, it also remain a possibility that Earth just now is passing a temperature peak, and that global temperatures will begin to decrease within the coming 5-10 years. Only time will show which of these possibilities is the correct."

  18. michaelkourlas, temperature is not global warming, the trend in temperature is. And, as will be repeated over and over, short term trends has no meaning whatsoever, even just statistically. Look critically at the data shown, ask for the uncertainty in the determination of the trends, look at the determination coefficient (whre shown). And take care, making hypothesis is easy untill you confront them with the known science. Any claim need to be justified quantitatively, which i can't see in the link you posted. Remember, climate change has (don't know why) a strong emotional impact on people, both "alarmists" and "deniers". The most conservative choice is stick to an expert advice, from climatologists; it's the very same thing we all do in our daily lives.
  19. How does this jive with what Phil Jones is saying now that there has been no warming since 1995. Climategate U-turn as scientist at centre of row admits: There has been no global warming since 1995 http://tr.im/O7vd How can it be both?
  20. VinceOZ at 17:17 PM on 14 February, 2010 Try as the Mail did to spin the interview, there's really not much there. Here's the part I found most shocking: "Discussing the interview, the BBC’s environmental analyst Roger Harrabin said he had spoken to colleagues of Professor Jones who had told him that his strengths included integrity and doggedness but not record-keeping and office tidying." Tut-tut. Lots of integrity but he can't keep his office tidy. Surely he must go. Vince, what say you to the graph in #40, here?
  21. hint: don't take Mail Online words for it. Further down you'll read "The trend is a warming trend". There's clearly something wrong in what they report.
  22. Update. As I suspected but could not prove (yet), it was not what Jones said. Here's is the full quote from the original BBC interview: "Question - Do you agree that from 1995 to the present there has been no statistically-significant global warming Answer - Yes, but only just. I also calculated the trend for the period 1995 to 2009. This trend (0.12C per decade) is positive, but not significant at the 95% significance level. The positive trend is quite close to the significance level. Achieving statistical significance in scientific terms is much more likely for longer periods, and much less likely for shorter periods. " So, once again, at the Daily Mail they showed that they do not understand science but unrelentlessly continue to misguide they readers.
  23. "Did global warming stop in 1998?" Did global warming START in 1998? U.S. Data Since 1895 Fail To Show Warming Trend LINK WASHINGTON, Jan. 25— After examining climate data extending back nearly 100 years, a team of Government scientists has concluded that there has been no significant change in average temperatures or rainfall in the United States over that entire period. While the nation's weather in individual years or even for periods of years has been hotter or cooler and drier or wetter than in other periods, the new study shows that over the last century there has been no trend in one direction or another. The study, made by scientists for the National Oceanic and Atmospheric Administration was published in the current issue of Geophysical Research Letters. It is based on temperature and precipitation readings taken at weather stations around the country from 1895 to 1987. ...

  24. Cowboy at 16:42 PM on 8 March, 2010 21 years ago that was the latest news. Almost quaint, but for some reason it's finding a lot of currency in the past few weeks. Here's some more of that same article, helping to provide full context: "Dr. Kirby Hanson, the meteorologist who led the study, said in a telephone interview that the findings concerning the United States do not necessarily ''cast doubt'' on previous findings of a worldwide trend toward warmer temperatures, nor do they have a bearing one way or another on the theory that a buildup of pollutants is acting like a greenhouse and causing global warming. He said that the United States occupies only a small percentage of Earth's surface and that the new findings may be the result of regional variations. ... Dr. Hanson of NOAA said today that the new study does not in any way contradict the findings reported by the NASA scientists and others. He said that his study, in which he was joined by George A. Maul and Thomas A. Karl, also of NOAA, looked at only the 48 contiguous states. Dr. Hanson said that global warming caused by the greenhouse effect might have been countered by some cooling phenomenon that has not yet been identified and that the readings in his study recorded the net effect. ''We have to be careful about interpreting things like this,'' he said. One aspect of the study that Dr. Hanson said was interesting was the finding that the urbanization of the United States has apparently not had a statistically significant effect on average temperature readings. A number of scientists have theorized that the replacement of forests and pastures by asphalt streets and concrete buildings, which retain heat, is an important cause of rising temperatures. Dr. Hansen of NASA said today that he had ''no quarrel'' with the findings in the new study. He noted that the United States covered only 1.5 percent of Earth. ''If you have only one degree warming on a global average, how much do you get at random'' when taking measurements in such a relatively small area, he asked rhetorically. ''We are just arguing now about whether the global warming effect is large enough to see,'' he added. ''It is not suprising we are not seeing it in a region that covers only 1.5 percent of the globe.''
  25. The earth is still storing up heat, but temperatures are not showing it? Well, that's a bit hard to swallow and sounds fishy. The new ocean temperature buoy system shows it's not the sea that's storing it, and that has such a large thermal inertia that you'd expect it to lag anyway. If the air and land is not warming... what's storing the heat? Dark matter in my backyard?? I think the statement is another stall to keep everyone from seeing that reality has diverged significantly from previous predictions. I've been living in the same area for sixty years. I haven't seen anything to indicate a climate change above normal variations. In fact, it's April 04, 32 F. outside and snowing right now!
    Response: "The new ocean temperature buoy system shows it's not the sea that's storing it"

    Actually, the new ocean temperature buoy system (ARGO) does show that it's the sea that is storing up heat. The following is the measurement of ocean heat measured by ARGO down to 2000 metres deep and shows the oceans are steadily accumulating heat (von Schuckmann 2009):



    Apologies for repeating the same graph from my response to comment #40 but it seems repetition is required for this particular argument.

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