One or Two Warm Years is not Global Warming

This is just one of dozens of responses to common climate change denial arguments, which can all be found at How to Talk to a Climate Sceptic.


So 2005 was a record year, records are set all the time. One really warm year is not Global Warming.


This is actually not an unreasonable point, single years taken by themselves can not establish or refute a trend. So 2005 being the hottest globally averaged temperature on record is not convincing. Then, how about:

  • every year since 1992 has been warmer than 1992
  • the ten hottest years on record occurred in the last 15
  • every year since 1976 has been warmer than 1976
  • the 20 hottest years on record occurred in the last 25
  • every year since 1964 has been warmer than 1956
  • every year since 1917 has been warmer than 1917

The five year mean global temperature in 1910 was .8oC lower than the five year mean in 2002. This, and all of the above, come from the temperature analysis by NASA GISS

There is an interesting quote from that page:

Record warmth in 2005 is notable, because global temperature has not received any boost from a tropical El Niño this year. The prior record year, 1998, on the contrary, was lifted 0.2°C above the trend line by the strongest El Niño of the past century.

So, yes it is true that one record year does not make a long term trend, but that is clearly not the whole story.

This is just one of dozens of responses to common climate change denial arguments, which can all be found at How to Talk to a Climate Sceptic.

"One or Two Warm Years is not Global Warming" was first published here, where you can still find the original comment thread. This updated version is also posted on the Grist website, where additional comments can be found, though the author, Coby Beck, does not monitor or respond there.

More like this

Yes, one year can't prove climate change. Up to 100 years, you can't claim climate change. So these arguments is simply bunk.

Climate is defined as an average of weather patterns over a period of time, usually 30 years. So yes, 100 years is enough data. 30 years is enough data when the trend is strong enough, possibly less given reasonable assumptions about interannual variability and the thermal inertia of oceans.

Thanks for your dissmissive and unsubstantiated contribution though!

It's actually no more dismissive or unsubstantiated than your claim. It's simply a matter of redefining words to meet one's needs. There are decade long climate phenomena, but working in the decade time scale, you can't suggest anything really.

A little perspective is called for: Over 10k years ago wooly mammoths played in the Arctic region until they were frozen into permafrost. Our human ancestors then fished off the ice flows in the Bay of Biscay and glaciers covered the Great Lakes. Over a period of the next 8k years the ice gradually receded. About 1k years ago Vikings were sailing in the vicinity of Greenland and setting up thriving settlements. 0.5k years ago the area iced over again and the early ocean explorers, in trying to find a route through the Northwest Passage could not even get close and many perished in the ice. 0.1k years ago Amundsan sails through the NWP for the first time in recent history. It freezes up again soon after. 0.06k years ago several expeditions make it through the Northwest Passage. 0.03k years ago we have the first accurate method of measurements with satellites. Over recent years the wooly mammoths that were frozen in the ice are just starting to thaw out so I guess we have just come full circle. Boy I hope we do not have to go through a cycle like that again.

By Tim Jenvey (not verified) on 06 Feb 2009 #permalink

Hi Tim,

I'm sure some of the traversals you are citing were multi-year or dog-sled traversals. Do you have some specific expeditions in mind? Also, none of these have been commercially viable routes due to shallow waterways. But, it is not very important.

You characterization of the temperature record does not match any studies I have seen. Care to share your source? I think it really goes more like 10K-8Kbp rapid warming and deglaciation, next 8K generally stable, slight overall cooling trend, no global flucuations greater then ~.2, .3oC, then .8oC rise over the 20th century.…
(not meant to be self-citation, just there are plenty of primary sources referenced in that article.)

Thanks for the comment!

So except for your more precise "I think it really goes more like 10K-8Kbp rapid warming and deglaciation, next 8K generally stable" you appear to agree with my perspective. That the earth is getting back to where it was when the woolly mammoths got frozen.
Thanks for taking time to reply.

By Tim Jenvey (not verified) on 07 Feb 2009 #permalink

I do not think the wooly mammoths would agree with you as they have only just started the process of thawing out.
It would be good if we could reconstruct them from the DNA like some folks are suggesting. We could then get the answer direct from the 'mammothâs mouth', as it were.

By tim jenvey (not verified) on 11 Feb 2009 #permalink

I respect your desire to rebut this objection. However some of the arrowed statements in the answer section do not form an adequate response. For example to state every year since 1992 has been hotter than 1992 relies on the value of 1992 . 1992 may have been a particularly cold year . The same is the case with all similar examples. These should be withdrawn as part of an answer.
The statement regarding the 10 hottest years on record occuring in the last 15 does provide a more effective rebuttal as does the 20 in 25 scenario.

You're right Mr. Magoo. 1992 is a cherry pick, something Coby loves to criticize. 1992 WAS a particularly cold year, because of the Mt. Pinatubo eruption.

How about year-year changes as a measure of trend? I would be interested in seeing the result of "temperature(year) - temperature(year-1)" for each year during any relevant period. Or at least a record ow how many year-year changes that have shown a rise compared to how many that have shown a decline in temperature.

There might be estimates of this already, but I have not seen any. Or if there is any reliable data series publically avaliable, I could calculate this myself.

I appreciate both sides of the story but I am confused. Temperature data is predicated on the data being accurate and unbiased. Where were these temperatures taken? Sure if you planted a thermometer in the middle of a forest with no buildings and asphalt it'd be cooler than when the city arrives. Temperatures at airports are generally warmer as they have much more "black top" heating than other areas. So I don't wholly buy the temp test.

Second, as for temps rising and ice melting and oceans rising. What data is there on the amount of land reclamation taking place around the globe? If you have a pool and you keep throwing pebbles onto the first step into the pool that water needs to go some place right?


Temperature datasets are adjusted for factors such as heat island effect. Whilst some denialists like to make claims about this, the information is robust and is on the record for anyone to view and challenge. So far, no-one has been able to demonstrate that the adjustments are incorrect, and in any case, if you take the urban sites out of the record, it makes no appreciable difference to the results. Here is just one paper explaining how adjustments are necessary and how they have been done (from Canada):…

With regard to your second point about land reclamation, I am not sure what you are talking about, but you appear to be suggesting that land reclamation will somehow make sea levels rise because of all the extra material dumped in the ocean to reclaim land. Is that correct? If so, you should try and do some rough calculations yourself to see how much material it would take to cause a sea level rise - it might surprise you.

Hi mark,

WRT urban heat island effects, see this page:…

The effect is real but it has been accounted for and is small to begin with. It is small not because forests are not alot cooler than parking lots but because we are measuring changes in temperature, not absolute temperatures and also small becasue the amount of land that is urbanized is very tiny compared to the whole surface of the earth.

As mandas said for your second query the numbers you are concerned about are tiny. Using your analogy, I bet we are talking about grains of sand tossed in one at a time, not even pebbles!

Not too sure where to put this but this seems the most appropriate.

In March 2000 a Dr David Viner, a senior research scientist at the climatic research unit (CRU) of the University of East Anglia said within a few years winter snowfall will become "a very rare and exciting event".

He also said "Children just aren't going to know what snow is,"

Now of course AGW was to blame and the northern hemisphere was going to see less and less cold winters along the way the MET office made its now infamous prediction of a bbq summer.…

Fast forward 10 years and the northern hemisphere is facing another bitterly cold winter and i admit it is early days but the start of this winter is looking ominous.

So obviously the prediction made by Dr Viner was complete rubbish so a new theory was needed and here it is.

This qoute sums it up âHard winters like last yearâs or in 2005-2006 do not defy the premise of global warming, but rather confirm it.â

Now obviously these two predictions are a complete contradiction. You see this is the beauty of AGW in 2000 Dr Viner of CRU made a prediction based on his knowledge of the climate and what his computer model told him so of course because the last winters were mild he assumed they would be mild forever more. In the end his prediction was a complete flop.

So now after a few cold winters the new prediction based on exactly the same flawed logic as before is that we can expect more cold winters. I suspect this prediction will be a flop again and so the climate experts will flip flop along with it.

So my question is will AGW make the northern hemisphere winters warmer or colder at the moment the climate consortium have a bob each way how pathetic they are.

Just out of interest here is the headline from the MET office on October 28 2010

"Winter to be mild predicts MET office"

The Mail had this headline just one month later (28 November 2010)

"STAY INDOORS!" Police warn Britons to stay off the roads as temps fall to minus 10C and 15 inches of snow falls.

This story re-emerges in the denialsphere whenever there is snow in London.

So if one adherent of a position makes a flawed prediction, that disproves the position?

Besides, if you read the original article in the guardian (I did, Crakar. I know you didn't.)

Heavy snow will return occasionally, says Dr Viner, but when it does we will be unprepared. "We're really going to get caught out. Snow will probably cause chaos in 20 years time," he said.

There is plenty of time for him to be right.…

Once again (as always) you have failed to impress me,do you reject my reality and substitute it with your own on purpose or is this a subliminal process? Maybe it is an automated defence mechanism your puny brain employs to protect itself.

I can only assume by your vague response that you subscribe to the original theory espoused by Dr Viner and not the new and improved theory which states winters will become harsher. You do understand why there is a newer and improved theory dont you Skip, its because Viner now looks like an idiot and ergo so do you.

So i will ask again which of the two contradicting theories do you believe in and why do you reject the other?

I think it is wise to place much less confidence in regional predictions than global average predictions.

As for which prediction will win, we will have to wait and see. The temperature in Northern Europe is a very small piece of the puzzle, and since global warming is unequivocal, whatever happens will simply have to be added to our understanding of climate and weather.

Now, if on the other hand, it got colder on average all around the globe over the next twenty years, that indeed would demand an explanation. Potential causes that would not in anyway contradict the current theories of climate include large quantities of volcanic sulphates being spewed forth and significantly dimished solar irradiance.

These things can not be predicted (at present, maybe never) which is why climate models make "projections" not "predictions".

A prediction about winter temperatures in Britian in 10 or even 20 years is a very iffy thing.


I agree with the second half of your post however like Skip you have successfully avoided the critical response.

Let me ask you a simple question which requires a simple answer.

Scenario A, Do you think AGW was the cause of milder/warmer winters in the northern hemisphere in the early 2000's and will do so into the future complete with a reduction in snow so much so that little children will only experience it in the virtual world as Dr Viner states?


Scenario B, Do think AGW is responsible for the recent bone chilling winters complete with large amounts of snow and will continue to do so for the foreseeable future as stated by Dr Vladimir Petoukhov?

When I was doing my workout tonight and watching Monday Night Football my mind actually drifted to this issue (very rare when I'm watching sports).

I think I didn't give your argument enough credit, initially, Crakar.

Its fair to ask if Viner's prediction was cavalier, and if northern Hemisphere winters do *not* follow his 20-year prediction made in 2000, then yes he has egg on his face.

What he should have done was say what *I'll* say: It is uncertain exactly what the regional impact will be in the short run precisely because climate forecasts are very much stricken with an element of uncertainty--with one major exception: Temperatures, on average will continue to rise. The long term implications are dire, whether England has a record harsh winter this year or not.

Its still a cherry pick on your part, Crakar, but Viner should have been more guarded in his specific claims. That i will grant.

This is not a cherry pick Skip Viner made a predic...sorry projection that in a few years there will be so little snow that children would not get to experience it. This predic...projection was based primarily on the results of computer simulations.

Now i an not saying Viner is correct or incorrect but his projection is in complete contradiction to Dr Vladimir Petoukhov who now claims the recent bone chilling winters are caused by AGW he like Viner used computer simulations for his projections.

So with all bullshit aside is the nth hemisphere going to experience warmer or colder winters? Is this too much to ask?

By the way i looked up the definition of projection in my Encarta dictionary (north american edition) it had several definitions but the only relevant to us is:

estimate: an estimate of the rate or amount of something

The definition for prediction is:

1. statement about future: a statement of what somebody thinks will happen in the future

2. act of predicting: the making of a statement or forming of an opinion about what will happen in the future

As much as Coby likes to think i do believe climate scientists make predictions not projections.

I can't say, of course, but I could throw the same question at you: Is Australia going to have hotter or colder summers in 2020?

I'm actually holding a morbid hope that increased oceanic warming and subsequent pacific precipitation will bring more snow and thus better water tables into the Sierras, perhaps reviving the value of my Norther Nevada real estate--if not for me then maybe for my kids or theirs.

Yeah its a shitty attitude and I admit it; but what I'm *not* doing is risking any regional predictions--only the *global* one. Climate scientists would do well to be so guarded, as your post above indicates, and that much I concede.

Oh oh! Looks like the crackhead has been trawling around the deniersphere again! What's up crakar - can't find any stories or papers by yourself without help?

I did some quick research on this one and found dozens of references - but I am willing to bet crakar found this one on jo nova. Come on crakar - am I right or did you get it elsewhere? Is this the right link:…

But the real question is, what did Viner REALLY say, and do these apparently different predictions disagree?

Well, a quick look shows that Viner stands by his earlier prediction that winters (in the UK) will be generally warmer in the future, but when they are cold they will be very cold and most people will be unprepared for their severity.…

And interestingly enough, crakar's second link is to a German report which predicts snowier winters in Germany and northern Europe (ie Russia and Scandinavia) because of moist winds blowing in from the Barents and Kara Seas because of melting ice in the eastern Arctic. Note the difference in the two stories and locations?

Now, I don't know if both, either, or neither of the claims and predictions are accurate, and I won't speculate. But what I will say without fear of being wrong, is that once again crakar has demonstrated his spectacular ignorance and inability to do anything other than cut-and-paste denier crap, without even the slightest realisation or analysis of what he is doing.

Welcome back moron.

I knew it would not be long before you smelt the scent of blood in the water and as usual you pull some vague paper from out of your arse. All i did was ask a simple question and as usual not one of you morons have the capacity to answer it.

By the way we now have a third theory as to why the NTH Hemisphere is experiencing very cold winters:…

This one like all the others comes with the obligatory "spin baby spin" mentality. Let me hit the high points.

They also said a lack of data from the Arctic, where warming has been particularly strong in the last 10 years, and changes to the way sea surface temperatures are measured have led to an underestimate of the rate at which temperatures are rising.

Dr Pope said: 'We may be underestimating the warming.'

ME: so a lack of data means warming has been particularly strong and at the same easy to underestimate, i was thinking it meant a lack of data, well fuck me i'll be a monkeys uncle.

while the UK is currently experiencing a cold snap and last year had the harshest winter for 30 years, the scientists said the evidence for man-made global warming had grown even stronger in the past year.

'We are starting to see changes in the climate even in the UK which we can link to global warming. We're seeing more heatwaves and seeing fewer of these cold winters.'

Anyway Mandas why dont you have a go and tell me is AGW going to cause more snow and cold, less snow and cold or is it now actually slowing down but never the less still warming the planet?

Mandas - Now, I don't know if both, either, or neither of the claims and predictions are accurate, and I won't speculate.

Referring to this Mandas?.

The overall warming of the earth's northern half could result in cold winters

Our simulations reveal a rather pronounced nonlinear response of air temperatures and winds to the changes of sea-ice cover,â Petoukhov, a physicist, says. âIt ranges from warming to cooling to warming again, as sea ice decreases.â An abrupt transition between different regimes of the atmospheric circulation in the sub-polar and polar regions may be very likely.

Warming of the air over the Barents-Kara Sea seems to bring cold winter winds to Europe. âThis is not what one would expect,â Petoukhov says. âWhoever thinks that the shrinking of some far away sea-ice won't bother him could be wrong. There are complex teleconnections in the climate system, and in the Barents-Kara Sea we might have discovered a powerful feedback mechanism.â

By Dappledwater (not verified) on 29 Nov 2010 #permalink

crakar24 @28 "By the way we now have a third theory as to why the NTH Hemisphere is experiencing very cold winters:"

But we aren't. Last winter was the warmest on record, 5 degrees warmer than usual, at least where I live. However, in your arrogance (or ignorance) you assume that the conditions prevailing in your little corner of the world are those that apply everywhere. Even there, it was only the coldest in the last 30 years, hardly comparable with the warmest ever recorded. Conditions in your neck of the woods are not necessarily representative of the world as a whole or even of the hemisphere.

By Richard Simons (not verified) on 30 Nov 2010 #permalink

A follow up post to 27,

"I did some quick research on this one and found dozens of references - but I am willing to bet crakar found this one on jo nova. Come on crakar - am I right or did you get it elsewhere? Is this the right link:"

Does it matter where i got my information? Does associating my post with Jo Nova suddenly "magic away" the two contradictory theories? No it does not so what is your point?

"Now, I don't know if both, either, or neither of the claims and predictions are accurate, and I won't speculate"

You wont speculate because you dont know but yet you can say with hand on heart that i cut and paste denialist crap. What denialist crap Mandas the two links were from English newspapers quoting scientists stating two contradictory theories you really are digging deep into your bag of tricks arent you.

You then finish off with a welcome back note, tell me what is my crime here? Just because you bunch of lemmings are too stupid to question the high priests of the church of scientology does not mean i cannot. So when you stop acting like a baby who has had his rattle taken away from him maybe you can pull your head out of your arse grow a set of balls and tell me if the NTH hemi is going to get warmer or colder due to AGW.

Oh by the way you know how we dont build dams in this country anymore but instead build expensive power intensive desal plants instead based on the predictions of CSIRO and the BOM which claim Australa is going to get hotter and drier?

Well this Australian spring was the wettest in recorded history and yes i know this event and the ones Richard S talks about in post 30 are all caused by natural variability so does not prove a thing etc, etc, etc.


If you want to join the gang who haunt this place then that is fine but be warned i am no mood to suffer fools lightly. Your post is total crap you make assumption after assumption about "what i think" then construct your own reality around that to base your argument. Grow up you fool.

By the way Richard i heard this soon to be rare event has started killing people maybe you can put the grieving families at ease by explaining that if it was not for AGW they would have died sooner because it would have been colder thus no suffering or maybe that should be if it was not for AGW they would not have died from the cold at all because they would have been down the beach getting a sun tan instead.

because you bunch of lemmings are too stupid to question the high priests of the church of scientology does not mean i cannot

How many of us plagiarized fraud?

Go ahead and post Crakar; just stay away from the I'm-the-open-minded-and-enlightened-one-and-you're-all-blinded-drones bullshit. You're in no position and you know it.

So are you still trying to decide which contradictory catastrophic result will come to fruition or are you like Mandas and just accept that one of them will (hopefully) come true?

I am only posting because i like to piss you and Mandas off, so far so good. I have asked a simple question and so far not one of the ghosts that haunt this place have actually attempted to answer it. Then again that is not your priority is it.

Anyway whilst you and Mandas have been scrambling to prop up the church with name calling and avoidance there has been a mass migration going on, this mass migration has emitted more CO2 than the 3 of us could do in our life times. Of course i am talking about COP16 at cancun a luxury holiday resort in Mexico, the sole purpose of this massing of minds is to figure out a way to stop us from producing CO2 so they can emit more. Whilst the gorging at the cracked crab buffet goes on a number of great ideas have been floated to do this.

So far the major front runners are:

1, Force the western world to go back to WWII like rationing.

2, Putting mirrors in space to reflect sunlight.

3, Covering Green land in a massive blanket so it does not melt.

4, Sprinkling iron filings into the ocean so algea can suck up CO2

5, Seeding clouds (creating clouds to block the sun)

6, Artificial trees that will suck CO2 out of the air (do they need to look like trees?)

7, Painting roofs white

8, Man made volcanos that produce sulphates

Now have a good read of what the high priests are suggesting here Skippy my boy as they sit in a beautiful exotic location and then consider your role in all of this.

The blinded drones will view this as humanity working together to solve the greatest challenge mankind has ever faced whilst people that live in the real world will look at this and say "what the fuck was in that cracked crab?"

Who in there right mind would think you could get a fucking blanket to cover greenland, every point mentioned generates a similar response. These people are either nut jobs and if so we are all in a world of hurt or they are very smart and have absolutely no intentions of ever doing something so utterly stupid but to the mindless drones like yourself they can by themselves so time. Hopefully enough time to enjoy another all expenses paid at one of the worlds most luxurious locations in COP17.

So back to the two predictions, which one will be proven correct by the passage of time and which one will fall flat on its face?

"fall flat on its face?" Anyone who makes unqualified statements about the future where the climate and the oceans are venturing into unknown territory will definitely fall flat on their faces unless they're extremely lucky. Or insightful in a way noone can understand.

As far as Europe and North America are concerned there are several really, seriously weird things going on. The temperature in Nuuk (Greenland) was higher than the temperature in San Francisco a day or so ago - now that is well off the scale of what we're used to. Having the great advantage of no scientific qualifications or reputation to defend, my absolutely, totally confident prediction is that there are more surprising, off-the-wall, unpredictable observations yet to come.

But with increasing concentrations of GHGs in the atmosphere, these remarkable, counter-intuitive events will be mere frills and furbelows adorning the frame of an unambiguous picture. Some people will always focus on the frame rather than the picture, but that's their choice.

"But with increasing concentrations of GHGs in the atmosphere, these remarkable, counter-intuitive events will be mere frills and furbelows adorning the frame of an unambiguous picture. Some people will always focus on the frame rather than the picture, but that's their choice."

Nice! : )

crakar24: I am sorry if I made a mistake in assuming that you are in the UK. It was based on your repeated references to comments and predictions about the winters there.

From the rest of what you have written, I am rather confused about your actual views. According to conventional science:
1. Earth is heated mainly by visible radiation from the sun.
2. Energy is lost from Earth mainly as longer-wave radiation.
3. CO2 absorbs this longer-wave radiation.
4. The amount of CO2 in the atmosphere has increased by about 50% in the past century.
5. Most, if not all, of this increase has been a result of human activity.
6. The increased CO2 can be expected to reduce the radiation leaving Earth, resulting in an increase in global temperatures.
7. There are no known negative feed-back mechanisms of sufficient magnitude to counter the effect of the increasing CO2.

Where exactly do you take issue with this and what is the justification for your views?

By Richard Simons (not verified) on 30 Nov 2010 #permalink

Wonderful speech Adelaidy,

But which prediction will be proven correct?


We were given a prediction in 2000 that soon the poor little children will only know what snow is through the virtual world. AGW is going to see to that, due to milder winters. Yes Viner did state that we may get a rare event such as snow now and again but winter as we have know it is a thing of the past.

10 years later we have another prediction that states AGW will cause more and more bone chilling winters which of course is in complete contradiction to Viners statements.

Obviously both cannot be true now it is possible Viner is wrong but not because he is incompetent but because of a lack of evidence/better models or who knows what.

All i have asked is simply which of the two predictions do we now consider to be correct. Are we to expect more severe winters like recent times or are we to expect a return to the milder winters seen in the early 2000's.

Thats it, whilst i acknowledge the 7 points you listed above as worthy of further discussion there is no point discussing any of your 7 points as they bear no relavence to my question.

But seeing as you went to all the trouble i will state my position on your 7 points. Remember i have no interest in debating these 7 points i am merely stating my position for your satisfaction.

1, Agreed
2, When you say mainly do you mean there is another avenue for energy to be lost? Logic dictates there must be other wise energy would build up even without CO2 via WV etc. To answer your question yes energy is lost this way.

3, CO2 is one of a few yes

4, Not sure by how much, the official records show levels from 1959 and it was 313 ppm and in 2010 it is 387 which is not 50% i think the IPCC claim the ppm level in 1750 was 275ppm which would put it less than 50%. I think the point you are trying to make is the levels have increased and of course i agree with this.

5, Not sure how much has been from us, propably most i suppose.

6, In theory i agree i think the sticking point is by how much the general rule of thumb is 1C for a doubling or there abouts.

7, This is probably the crux of the issue, are there any -ve FB's to increasing CO2 or any other GHG? How strong are these FB's +ve or -ve? What is the sensitivity to these changes etc. All very good questions.

But as i said these do not influence the question that i asked.


Which prediction will be proven correct?

I'm riding the wave now. My prediction, watch carefully, is that just about anything will happen, the only problem is the timing. My supersensitive, unchallenged intuition is that the WACCy winters in the NH will cause a bit of consternation for several years yet. Once the Arctic settles down to several consecutive ice-free months every year, we'll have a lot more observations to make more reliable judgements about what might or might not happen during NH winters.

By that time, I'm expecting that more people will have their eyes on the encroaching shorelines than on their snowshoes.

Well credit where credit is due Adelaidy at least you had a go.

Basically what you are saying (and i agree) is both predictions are meaningless and should be ignored.

IF there is no ice in the Arctic then it may have an effect on NH winters and IF that time ever comes then we will indeed need to review what will happen.

Of course talk of the Arctic being ice free even for only a couple of summer months are merely flights of fancy and is just another prediction that should be ignored.

But thank you for having the balls that no others have had to answer my question.