Temperature Trends

2017 Was the Second Hottest Year Since 1880, Says NASA

It was the 41st consecutive year with global temperatures above the 20th-century average.



2017 was the second-warmest year since 1880, according to NASA. Only 2016 was warmer.

More specifically, NASA reports that globally averaged temperatures last year were 0.90° Celsius warmer than the mean temperature from 1951 to 1980. The three other major institutions that track global temperature trends find that 2017 is the third warmest year in their records.

The National Oceanic and Atmospheric Administration reports:

The average temperature across the globe in 2017 was 1.51 degrees Fahrenheit (0.84 degrees Celsius) above the 20th century average of 57 degrees Fahrenheit (13.9 degrees Celsius). 2017 marks the 41st consecutive year (since 1977) with global land and ocean temperatures at least nominally above the 20th-century average.

"The six warmest years on record for the planet," the agency adds, "have all occurred since 2010."

Researchers at the Met Office Hadley Centre and the University of East Anglia's Climatic Research Unit report that the global average temperature in 2017 was about 0.99° Celsius above pre-industrial levels, and about 0.38° Celsius above the 1981–2010 average.

The climatologists at the University of Alabama in Huntsville who oversee the satellite temperature data report that the average temperature in the lower troposphere over the globe in 2017 was 0.375° Celsius warmer than seasonal norms. These temperature trends are calculated relative to a 30-year average (1981–2010). The Huntsville satellite record trend, often cited by folks who are less concerned about climate model projections, is basically identical to the Hadley Centre's conclusions.


Remote Sensing Systems (RSS) also uses satellite temperature data to calculate global temperature trends. It reports that 2017

was the second warmest recorded since satellite observations began in 1979. Last year, 2016, was the warmest ever recorded. The near-record warmth of 2017 is notable because an El Niño event did not occur in 2017. The other 3 warmest years, 1998, 2010, and 2016, were El Niño years. Except for 1998, all of the warmest years occur after 2000, providing clear evidence of global temperature increase in the troposphere.

RSS notes that the although the recent warm years have brought climate model projections and measured temperature trends closer, it is still the case the "the troposphere has not warmed quite as fast as most climate models predict."

The Huntsville researchers find that the globe is warming at 0.13° Celsius per decade, while RSS reports a warming trend of 0.18° Celsius per decade. The surface data trends fall within this range. It is generally agreed that the earth has warmed by about 1° Celsius since the 19th century.

If the Huntsville rate of temperature increase is maintained for the rest of this century, the world would end up just a bit over 2° Celsius warmer than it was around 1900. If the RSS trend is sustained, that would yield a further increase of nearly 1.5° Celsius, resulting in a global average temperature that's 2.5° Celsius warmer than it was in 1900. It is worth noting that the temperature difference between now and the last ice age is between 4 to 7° Celsius. That increase occurred at a much slower pace.

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  1. Meanwhile here in St. Louis, we just had like the 6th coldest stretch of Winter since they started keeping records.

    1. That’s because of the warming.

    2. We have now this winter had 2 snowfalls of over 4″ here in Atlanta, which is not a lot except we never get snow. If this global warming crap keeps up, Atlanta might have to actually invest in road clearing equipment.

      1. You can probably buy it from us in Alaska. We’re getting 66F in January (35 degrees above averages).

  2. Ron – Do you know how much of the temperature increase is polar vs ‘global’? Cuz I’ve always thought any polar increase could have a separate/supplemental cause (namely weakening of the magnetic field as preliminary to a reversal – which is prob happening now)

    1. JF: Polar rate of increase is more than double the global average.

      1. So if the polar rate of increase is double the global average, then wouldn’t that imply that non polar areas are warming less than the global average? How much does the “polar rate of increase” play into the overall global average increase?

        1. idk the answer to your question – but any polar change will have very weird rather than consistent effects on surface temperature outside the poles because of the polar vortex (the permanent low pressure system centered there). Maybe it just gets hotter, maybe it spreads out and gets bigger, or contracts and gets faster

  3. Let us say for a moment, that the temperature increase is accurate. So the world has warmed almost a full degree C. And what are the negative effects? Hell the Maldives are still not below the surface.

    So if the world warms by another degree C, then it will be catastrophic?

    We can argue over the data all we want. But there is ZERO proof that this amount of warming is necessarily a bad thing anyway.

    1. There’s zero proof of anything, to you, when you go out of your way not to read about the subject.

      1. Tony|1.18.18 @ 6:21PM|#
        “There’s zero proof of anything, to you, when you go out of your way not to read about the subject.”

        There’s zero evidence you have an IQ above freezing, dipshit.

        1. Fahrenheit, Celsius, or Kelvin?

      2. Ask Greenland, our next bread basket.

  4. I don’t know if I trust the Rutherford B. Hayes administration’s satellite data.

    1. I didn’t even know NASA was around in the 1880s.

      1. That’s the joke.

        1. And that we only have a short record of relatively accurate satellite data.

          1. We only have a short record of relatively accurate meteorological data of any kind.

    2. I find it easier to believe that two Yankee Professors could lie than to admit that CO2 could warm the heavens

      – FOE

      You anti-science denying denier!

      1. The only science I believe in is the science of the BMI. It’s the only science that’s backed by facts I can see.

        1. Body mass index? Yeah, fat don’t lie.

        2. ASCAP is way more scientific than BMI.

  5. I’m not seeing the emergency. “2017 Was the Second Hottest Year Since 1880, Says NASA” doesn’t require a government program.

    1. L,J: My preferred way to solve any of the problems that might arise as a result of man-made global warming.

      1. Thanks, Mr. Bailey. I’m happy that gets exposure beyond this site. Have to admit I dropped my sub to SA some years back when it seemed to become more interested in promoting a certain bias.

  6. And BTW: maybe you can help me understand something. “Pre-industrial” temperatures were taken and recorded how? I am assuming with mercury thermometers? Are we measuring the temperatures the same way, at the same points, controlling for “heat-island” effects? I am not trying to be argumentative, but I think it is an important thing to know.

    1. Another similar thought that has flitted across my mind recently (especially in the context of is warming, and carbon, bad?): distinguishing renewables from carbon. Being clearer; the notion of ‘dinosaurs died and get compressed to oil in the crust’ only really applies to older oil production methods and is, arguably, a bit of propaganda. Oil, especially relatively pure oil (let alone plastic), is pretty stable and environmentally benign and the infrastructure for transporting, consuming and even recycling it is already in place. It seems entirely probable that if there is a ‘renewable future’, it includes carbon and plastics (as renewables).

    2. “Pre-industrial” temperatures were taken and recorded how? I am assuming with mercury thermometers?

      Some were hi-low for the day, others were time of day. There are a lot of other issues with the data sets such as the adjustments that cool the past and warm the present. NASA’a claim the the global mean change is accurate to within 0.1 degree is laughable as is extrapolating temperatures 1200 km’s away.

      1. No. The data are perfect. Heretic.

        1. No. The data are perfect. Denier Heretic.

          Now get it right the next time!

  7. The 2016 El Nino will be a real test to me.

    By eyeball, the 1998 El Nino produced a stair step increase in average temp. Will 2016 do the same? If the cold rebound pattern of 1998 holds, it will take a few years to know. If we don’t get a cold rebound, but continue at roughly 2017 levels, that would make a big jump in the trend.

  8. Meanwhile, in VA, we haven’t had an overnight low of legal age in 2 weeks.

    1. RS: As a Charlottesville resident, I hear you!

  9. So, I saw a couple of days ago that an area of Russia reached -88F (-66C). Does that mean somewhere on Earth an area will reach 200F (93C) to average out global temp?

    1. Yep: the inside of your mom.

      1. Lube, man. Use the lube.

  10. “The six warmest years on record for the planet,” the agency adds, “have all occurred since 2010.”

    Wait, what?

    1. All the years on the record are warm but of the last seven years, six were the most warmest. It’s one of Gosset’s lesser known but time-tested statistical analytical methods; pick the top 6 of 7 in no particular order, place them on a barn and draw a circle around them.

      As a side note, when I pick cherries, six of the first seven that can reach from the ground are always the warmest. Just more proof that carbon is actually physically warming the globe, I mean changing the climate, no, no, warming the globe… yes! Warming the globe.

      1. You have to try very hard to be this incapable of understanding what’s being said here.

        1. And you don’t have to expend any effort at all to fail to understand.

      1. But since it’s O’Neil, it probably just fine; I’ll take a look after finishing the comments.

  11. I have a hard time getting totally worked up about this subject. We are currently living in the Quaternary Ice Age. To be clear, it’s an interglacial period within an Ice Age. If you are out mowing your lawn during any part of an Ice Age, you really should expect things to get warmer at some point.

    1. No, dude. It’s Armageddon.

    2. But we know what’s causing this warming.

      1. But we know what’s causing this warming.

        LMAO … Sure we do Tony. I think the correct word would be “believe”.

        1. GregF, yet another Reason commenter who’s more of an expert than the entire scientific community of planet earth.

          What a rare collection of minds we have here.

          1. Tony,
            You would have swallowed Eugenics hook, line, and sinker just like “the entire scientific community” did. History tells us that what “the entire scientific community” believes is quite often very wrong. Anytime you actually want to discuss the science I am all ears. Appeals to authority are not an argument.

            1. The entire scientific community endorsing something also is not evidence of the opposite of what they claim, which is kind of what you’re trying to say. Listen to yourself. It’s ridiculous. The entire scientific community thinks the earth is roughly spherical too. Are they more likely to be wrong because of their unanimity? Good lord.

              An appeal to authority is an argument if the authority is the entire scientific community. It’s a good argument. Hard to refute. You don’t want to talk about the underlying science, you want to poke holes in it where you think you can in order to further your political agenda, which has nothing to do with appreciating scientific fact.

              1. The entire scientific community endorsing something also is not evidence of the opposite of what they claim, which is kind of what you’re trying to say.

                Let me spell this out since you appear to be quite dense. What the “the entire scientific community” endorses is not science. To assess the validity of any science you actually have to look at the data. You have to ask does the data support the hypothesis. If it doesn’t then the hypothesis is wrong no matter how many of the “scientific community” believe it’s true.

                An appeal to authority is an argument if the authority is the entire scientific community.

                That is why I said. You would have swallowed Eugenics hook, line, and sinker just like “the entire scientific community” did. You appear to be stupid to see why appeal to authority is never a valid argument.

                You don’t want to talk about the underlying science, you want to poke holes in it where you think you can in order to further your political agenda …

                Oh my Tony you really are ignorant. Science advances because people actively try to “poke holes” in theories. You problem Tony is you don’t know shit about science. Your half ass remark about “political agenda” is commonly referred to as projection. The “science” you believe in is nothing but a modern day religion.

                1. It’s important to remember what the scientific community is endorsing. The famous 97% comes from a survey in which 97% agreed that the earth is warming and humans play a significant part in this warming.

                  This is not a particular damning statement. Over what period of time? The earth is coming out of an ice age, so yeah the earth is warming. And humans play a significant part. What is significant? Is that half of warming? Is 20% significant? And perhaps most importantly, there is no consensus regarding if this is a bad thing, what the impacts will be, what could mitigate these impacts, and are they worth attempting?

                  Additionally, and individuals motivations does not make for bad science by itself, however, there is very strong motivation for researchers to proclaim gloom and doom scenarios. Which position will get more attention and funding?
                  1 – The earth is warming slightly, and we don’t know if this is bad or what the impacts might be, so give me money to study it.
                  2 – The earth is burning up! We are all going to fry to crisp and be flooded by the oceans! We need to act immediately! I need money to do a study telling me I am right and that you need to listen to me!

              2. Tony, you’re the one that scurries away as soon as any references or data is discussed. Those walls in your glass house are remarkably thin.

  12. Wow. Practically galactic time scales.

  13. I appreciate Bailey’s roundup of sources instead of just relying on the Alabama guys. Of course it’s journalistic malpractice to throw out changes in degree numbers when you know full well that your readers don’t know the difference between the planet and the thermostat in their house.

    This comments section starts out with someone implying that global warming is a hoax because it’s snowing where they live. These people need a lot of help. They haven’t managed to get beyond even that.

    1. Actually only you don’t know the difference. We understand just fine.

      We don’t imply its a hoax because its snowing (though of course when its a 100 degrees that PROVES its true). We imply its false because the data and the science doesn’t support it. This “hottest year on record” BS is only due to our lack of temperature history and inaccuracies in the history we do have.

  14. I appreciate Bailey’s roundup of sources instead of just relying on the Alabama guys.

    He didn’t provide any sources. Just press releases.

    1. GF: Which provide links that then take you to sites that will guide you to the scientific literature if you are so inclined to read through the studies that can be found there.

      1. That’s only slightly better than claiming that https://www.reason.com will get you to the literature.

        I guess someone subscribes to the Raven Paradox.

      2. Ron,

        This has nothing to do with studies. The temperature data sets are just a table of time series data. You start out with “2017 was the second-warmest year since 1880”. The GISS web page you pointed to says:

        Earth’s global surface temperatures in 2017 ranked as the second warmest since 1880, according to an analysis by NASA.

        They also claim (LMAO):

        NASA estimates that 2017’s global mean change is accurate to within 0.1 degree Fahrenheit, with a 95 percent certainty level.

        The data set is here
        So lets look at the claim of “second warmest”. They state that 2017 was .9 +/- .1 meaning it was somewhere between 1.0 and .8 degrees. 2015 was between .96 and .76, 2014 was between .83 and .63. and 2016 was between 1.09 and .89. Taking the uncertainty into account the only honest statement about 2017 is it could have been anywhere from the 1st to 4th warmest in the record.

        On top of that is the 95% uncertainty which means statistically there is a 1 out of 20 chance that the real value is outside the +/- .1 degree range.

  15. I post this NASA map of global CO2 distribution for you to consider:

    Note that the range is only 10 ppm (essentially meaningless). However, note also that the regions that have the highest CO2 concentration do not correspond to the greatest warming, such as the arctic. And the NASA website notes that CO2 is NEITHER the most potent, nor most abundant greenhouse gas. It looks like this was last updated in 2013, so long before the anti-science antichrist could have messed with it (Sorry Tony).

    The temperatures here are surface temperatures, and the CO2 data is from the upper troposphere. My take from this is that yes, there has been some warming over the past decade, but nobody really knows what is causing it.

  16. So, per the article… models predict X . Observed data shows A . A is not equal to X. Therefore, the models are correct. Got it!

    1. I think. . .

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