A commenter just asked on the original "One or two warm years is not Global Warming" thread if the article is still true five years later.
Certainly the logic of it, that the temperature trend is unequivocally warming and we are not claimig global warming because of a record or two, still holds, but I thought it might be interesting to revisit the specific data points I raised in it and ask if they are still true.
The temperature data points are from the GISS analysis and can be found here (as you see, I have discovered where they hide their data!).
The statements I made are as follows:
every year since 1992 has been warmer than 1992Still true.
the ten hottest years on record occurred in the last 15Still true, in fact we can now up that to the ten hottest years have occurred in the last 12.
every year since 1976 has been warmer than 1976Yes, absolutely.
the 20 hottest years on record occurred in the last 251981 and 1983 with anomalies of .26oC have slipped out of that window so we can now only claim 18 of the hottest years in the last 25.
every year since 1964 has been warmer than 1956I think this was a typo, because then, and now, every year since 1964 has been warmer than 1964!
every year since 1917 has been warmer than 1917This is a very safe datapoint.
The five year mean global temperature in 1910 was .8oC lower than the five year mean in 2002The five year mean in 2006 (the last year for which this can be calculated) is .05oC higher than it was in 2002.
I would venture to predict that global average temperatures will not be below 1974 levels for some number of centuries, notwithstanding some catastrophic volcanism or miraculous technological development.
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It's also worth pointing out that global warming refers to global climate, which is completely different to local climate, and even more different to local (or even regional/global) weather - a concept which appears to confuse many otherwise intelligent people.
Of course, that's why many scientists (esp. climate scientists) also use the terminology 'climate change' as opposed to 'global warming'.
Posted by: aimeew | February 1, 2010 9:22 PM
No matter how one looks at it, the amount of warming over the past century or so is nothing unusual. It's well within normal operational parameters of natural climate change. Sorry, but AGW alarmists have nothing and are just using scare tactics in the worst possible way (ie, exaggerations and corrupted science) to frighten everyone into action.
Posted by: Peter of Sydney | February 1, 2010 11:54 PM
"No matter how one looks at it, the amount of warming over the past century or so is nothing unusual. It's well within normal operational parameters of natural climate change" - POS
Incorrect, the rate of temperature increase is occurring much faster than the last large extinction event, the Paleocene-Eocene Thermal Maximum, 55 mya. That in itself was an unusual event.
Posted by: Dappledwater | February 2, 2010 1:04 AM
No matter how one looks at it, the amount of warming over the past century or so is quite unusual. It's well outside normal operational parameters of natural climate change. Sorry, but AGW denialists have nothing and are just using libel in the worst possible way (ie, exaggerations and claims of corrupted science) to frighten everyone from action.
In other words, Mr Peter, you are full of shit.
Posted by: Jean-Denis Muys | February 2, 2010 1:15 AM
Thanks Jean. Your tone and language just proves that I'm right and you are wrong. I suppose next you are going to say we never had a MWP and that temperatures now are higher than back then. Are you a member of the discredited and infamous hockey stick team?
Posted by: Peter of Sydney | February 2, 2010 1:18 AM
I checked the Greenland and Vostok ice core temperatures, and nothing jumps out at a first glance.
http://www.foresight.org/nanodot/?p=3553
Posted by: romunov | February 2, 2010 1:31 AM
"Your tone and language just proves that I'm right and you are wrong"
I'm confused Peter - How can tone & language affect the science? If I said "gravity sh*tting exists motherf*cker" would that mean we would all start spiralling off into space?
I'm also confused as to how you can respond to post #4 and not to post #3. Does that mean Dappledwater is right & you are wrong? How can you be both right and wrong? Something to do with quantum I suppose...
Posted by: Chris S. | February 2, 2010 1:36 AM
@romunov: you do not see anything unusual, because it lacks just about ALL the warming of the 20th century. Not included in the figures. Just so you know, in several place on Greenland, the warming since 1900 is about 2-3 degrees Celsius. Just plot that into the figures...
And unlike the claim in your link, it isn't the "hockeystick" climatologists who claim only CO2 can explain most of the recent warming. That claim actually comes from OTHER climatologists. Those that study the causes of climate change, not those that study historical climate.
Posted by: Marco | February 2, 2010 2:58 AM
Post 9 is spam.
Peter of Sydney - the current warming is only the start, we are due another degree or so even if we stop emissions of all greenhouse gases,changes in land use etc. We know that the warming is caused by CO2 because of stratospheric cooling. If it was caused by the sun the entire atmosphere would be warming, including the stratosphere. WE can also model the climate to show that without the CO2 and other gases, the warming of the last 30 years would not have occured.
So what are the normal operational parameters of the climate then? Do you have any evidence for this?
Posted by: guthrie | February 2, 2010 5:39 AM
http://cartoons.nytimages.com/wieck_preview_page_210565
Of course Peter has no evidence - denialists dont need any, because they simply know the "truth".
And shown the facts they just claim that the evidence is corrupted and the conclusions are exxagerated - just because they simply know the "truth".
How is it possible to convince someone so entrenched in his fanatism? Thats a problem.
Posted by: facepalm | February 2, 2010 9:37 AM
"Incorrect, the rate of temperature increase is occurring much faster than the last large extinction event, the Paleocene-Eocene Thermal Maximum, 55 mya. That in itself was an unusual event."
If you believe that the numbers aren't fudged or tampered with in some way. Until that matter is addressed everything mus be questioned.
Posted by: trugreen | February 2, 2010 2:36 PM
Number 9 was not spam. It was a legitimate comment that the blog owner disagreed with and erased/censored the post becuase he disagreed with the content. AKA climategate. That's waht happened to my post, that's what happened at the IPCC. Censorship sucks.
Posted by: trugreen | February 2, 2010 6:23 PM
The former post #9 was one of three posted at the same time promoting the same commercial URL, aka spam.
trugreen has not had any comments of his/hers removed.
Posted by: coby | February 2, 2010 6:34 PM
"every year since 1992 has been warmer than 1992"
I think these were bad statements to make. Not every year since 1998 has been warmer than 1998; what of that?
The main point to emphasise is the trend, while reminding there is noise on top so it's not a monotonic increase.
But when people get excited by the wiggles, it is good to remind them that even with the wiggles, it's still nowhere close to the temperature of 1970.
Posted by: carrot eater | February 3, 2010 5:30 AM
Hi carrot eator,
I don't disagree with your main point at all. The OP was an attempt to respond to a "wiggle" argument in kind, but you are correct that the wiggles are a distraction that good statistics easitly removes.
Re 1998, if it remains true for another ten years that no other year is clearly warmer (ie in CRU as well as a larger margin in GISS), it will probably be significant.
Posted by: coby | February 3, 2010 2:51 PM
Hello there Coby,
Hope all is well with you, i just wanted to ask for a clarification of what you said. Are you saying if the temps do not rise (ie stay the same) for another ten years then that would be significant? As in a need for a rethink on AGW significant or have i misread what you said. The reason i ask is because it would only be 20 years and not thirty thats all.
Posted by: crakar24 | February 3, 2010 6:05 PM
10 years was not carefully thought out but I am comfortable with it though we are bumping against the narrow limits of my understanding of statistics.
In 2020 it will be possible to determine the trend in the 30yr mean global temperature from 1998 to 2005. That is a short time, but it is a statistically meaningful window to average. If no year has significantly exceeded 1998 by then, then the trend would be known to be 0 or negative right now.
This would require as explanation, whatever it would be (volcanoes like crazy in the 2010s, the sun went out, Lindzen's Iris effect happened for the first time in geological history, CO2 stopped being radiatively active).
Check this post for more detail and a link to Open Mind asking the question, when will we get a new record?
http://scienceblogs.com/illconsidered/2009/07/so_when_will_we_get_a_new_temp.php
Posted by: coby | February 3, 2010 6:55 PM
Regarding how long one would expect to wait before a new record year: RC took a shot at that as well, using model results.
See the third figure here.
http://www.realclimate.org/index.php/archives/2008/05/what-the-ipcc-models-really-say/
Posted by: carrot eater | February 4, 2010 6:41 PM
Thanks for following this up.
I have been working hard on some contrarians who are up-to-the-minute on the latest climate "scandals" such as the Himalayan "fiasco" etc etc. It is wearing, but I enjoy the fight, and I'm winning them over slowly.
Keeping this site and the data up to date helps, but on the other hand, seeing that it was 5 years out of date, I went and did my own research, and (independantly) discovered the same things that you did.
Posted by: Dylan | February 9, 2010 10:52 PM
and I'm winning them over slowly.
Maybe you could pinch hit for me with Crakar for a week?
Posted by: skip | February 9, 2010 11:20 PM
What the!!!, a week? thats alright Skip you go off on a weeks holiday dont worry about me. I will box a few rounds with this Dylan character but it wont be the same, you know that.
Posted by: crakar | February 10, 2010 5:10 AM
Here's looking at you, kid.
Posted by: skip | February 10, 2010 7:29 AM
Thanks for the offer. Actually, arguing with climate contrarians in online comment sections can be fun, but I would question the usefulness here where most everyone either understands AGW, or is a troll.
Much better to talk in other forums where the population is more generic, and you will win more converts.
Posted by: Dylan | February 10, 2010 11:03 PM
here is blog that counters the people who feel that "GLOBAL WARMING IS NOT REAL!!".Check it out.. http://mrinalc.blogspot.com/2010/03/global-warming-are-we-concerned.html
Posted by: Mrinal | March 5, 2010 11:05 AM
If it is true that man-created CO2 has been the cause of the earth heating up so "catastrophically" since 1988, then please can you explain how it is that the Romans used to grow wine in Northern Scotland?
The evidence is that the earth has warmed by .8 degrees celcius since 1900, but that the earth has been far warmer during earlier periods (also far colder), and that we are in a mild warming cycle which is completely natural.
Posted by: lojolondon | June 30, 2010 9:55 AM
"and that we are in a mild warming cycle which is completely natural." - lojo
Yeah, and murder is impossible because people die of natural causes all the time eh?. By the way, what "natural" mechanism is causing the warming if not the extra CO2 humans have put into the atmosphere?.
Posted by: Dappledwater | June 30, 2010 2:32 PM
lojolondon
".....If it is true that man-created CO2 has been the cause of the earth heating up so "catastrophically" since 1988, then please can you explain how it is that the Romans used to grow wine in Northern Scotland?..."
The Romans never grew wine - in northern Scotland or anywhere. Wine is not a crop, and cannot be grown. You can grow a variety of crops such as grapes from which you can make wine, and the Romans certainly did this in a lot of places. But there is little evidence to suggest that they ever did it in Britain at all - in any quantity at least - and certainly not in northen Scotland. If you remember your history (sorry - apparently you don't) the Romans never occupied northern Scotland - the local tribes there offered fierce resistance. You may have even heard of a little thing called Hadrian's Wall.
So here's a little tip. If you want to come in an discuss the issue of climate change, please don't do so from the position of a completely ignorant moron (Oh, sorry. You are a denier. Being a completely ignorant moron goes with the territory).
Posted by: mandas | June 30, 2010 5:19 PM