Guest post by Dr. Don J. Easterbrook
1934 has long been considered the warmest year of the past century. A decade ago, the closest challenger appeared to be 1998, a super-el nino year, but it trailed 1934 by 0.54°C (0.97°F). Since then, NASA GISS has “adjusted” the U.S. data for 1934 downward and 1998 upward (see December 25, 2010 post by Ira Glickstein) in an attempt to make 1998 warmer than 1934 and seemingly erased the original rather large lead of 1934 over 1998. The last phases of the strong 2009-2010 el nino in early 2010 made this year another possible contender for the warmest year of the century. However, December 2010 has been one of the coldest Decembers in a century in many parts of the world, so 2010 probably won’t be warmer than 1998. But does it really matter? Regardless of which year wins the temperature adjustment battle, how significant will that be? To answer that question, we need to look at a much longer time frame‒centuries and millennia.
One of the best ways to look at long-term temperatures is with isotope data from the GISP2 Greenland ice core, from which temperatures for thousands of years can be determined. The ice core isotope data were obtained by Minze Stuiver and Peter Grootes from nuclear accelerator measurements of thousands of oxygen isotope ratios (16O/18O), which are a measure of paleo-temperatures at the time snow fell that was later converted to glacial ice. The age of such temperatures can be accurately measured from annual layers of accumulation of rock debris marking each summer’s melting of ice and concentration of rock debris on the glacier.
The past century
Two episodes of global warming and two episodes of global cooling occurred during the past century:
1880 to 1915 cool period. Atmospheric temperature measurements, glacier fluctuations, and oxygen isotope data from Greenland ice cores all record a cool period from about 1880 to about 1915. Many cold temperature records in North America were set during this period. Glaciers advanced, some nearly to terminal positions reached during the Little Ice Age about 400 years ago. During this period, global temperatures were about 0.9 ° C (1.6 ° F) cooler than at present. From 1880 to 1890, temperatures dropped 0.35 ° C (0.6° F) in only 10 years. The 1880 –1915 cool period shows up well in the oxygen isotope curve of the Greenland Ice Sheet.
1915 to 1945 warm period. Global temperatures rose steadily in the 1920s, 1930s, and early 1940s. By the mid-1940s, global temperatures were about 0.5 °C (0.9° F) warmer than they had been at the turn of the century. More high temperature records for the century were recorded in the 1930s than in any other decade of the 20th century. Glaciers during this warm period retreated, temperatures in the 1930s in Greenland were warmer than at present, and rates of warming were higher (warming 4°C (7° F) in two decades). All of this occurred before CO2 emissions began to soar after 1945, so at least half of the warming of the past century cannot have been caused by manmade CO2.
1945 to 1977 cool period. Global temperatures began to cool in the mid–1940’s at the point when CO2 emissions began to soar. Global temperatures in the Northern Hemisphere dropped about 0.5° C (0.9° F) from the mid-1940s until 1977 and temperatures globally cooled about 0.2° C (0.4° F). Many of the world’s glaciers advanced during this time and recovered a good deal of the ice lost during the 1915–1945 warm period. Many examples of glacial recession cited in the news media show contrasting terminal positions beginning with the maximum extent at the end of the 1880-1915 year cool period and ending with the minimum extent of the recent 20 year warm period (1977-1998). A much better gauge of the effect of climate on glaciers would be to compare glacier terminal positions between the ends of successive cool periods or the ends of successive warm periods.
1977 to 1998 global warming The global cooling that prevailed from ~1945 to 1977 ended abruptly in 1977 when the Pacific Ocean shifted from its cool mode to its warm mode in a single year and global temperatures began to rise, initiating two decades of global warming. This sudden reversal of climate in 1977 has been called the “Great Pacific Climate Shift” because it happened so abruptly. During this warm period, alpine glaciers retreated, Arctic sea ice diminished, melting of the Greenland Ice Sheet occur.
The abruptness of the shift in Pacific sea surface temperatures and corresponding change from global cooling to global warming in 1977 is highly significant and strongly suggests a cause-and-effect relationship. The rise of atmospheric CO2, which accelerated after 1945 shows no sudden change that could account for the “Great Pacific Climate Shift”.
1999 to 2010 global cooling. No global warming has occurred above the 1998 level and temperatures have declined slightly.
The past 500 years
Temperature oscillations recorded in Greenland ice cores over the past 500 years (Fig. 2) are truly remarkable. At least 40 periods of warming and cooling have occurred since 1480 AD, all well before CO2 emissions could have been a factor.
The past 5,000 years
Figure 3 shows oxygen isotope ratios from the GISP2 Greenland ice core for the past 5,000 years. Note that temperatures were significantly warmer than present from 1500 to 5000 years ago.
The past 10,000 years
Most of the past 10,000 have been warmer than the present. Figure 4 shows temperatures from the GISP2 Greenland ice core. With the exception of a brief cool period about 8,200 years ago, the entire period from 1,500 to 10,500 years ago was significantly warmer than present.
Another graph of temperatures from the Greenland ice core for the past 10,000 years is shown in Figure 5. It shows essentially the same temperatures as Cuffy and Clow (1997) but with somewhat greater detail. What both of these temperature curves show is that virtually all of the past 10,000 years has been warmer than the present.
So where do the 1934/1998/2010 warm years rank in the long-term list of warm years? Of the past 10,500 years, 9,100 were warmer than 1934/1998/2010. Thus, regardless of which year ( 1934, 1998, or 2010) turns out to be the warmest of the past century, that year will rank number 9,099 in the long-term list.
The climate has been warming slowly since the Little Ice Age (Fig. 5), but it has quite a ways to go yet before reaching the temperature levels that persisted for nearly all of the past 10,500 years.
It’s really much to do about nothing.
HenryP says:
January 5, 2011 at 10:24 pm
“henry@Wheels OC/ Frm Peru
http://wattsupwiththat.com/2009/12/09/hockey-stick-observed-in-noaa-ice-core-data/
So, you say that J. Storrs Hall was also wrong by asserting that things have been a lot warmer in the past and that the current warming ‘hockey stick’ is dinky compared to what happened in history?”
Absolutely YES. The same capital mistake that Dr. Don J. Easterbrook has done: chopping off the last 105 years of warming.
And before you say “in the last 105 years there is still no ice core record” remember that there is an instrumental temperature record!
HenryP says:
January 5, 2011 at 9:49 pm
“From Peru says
Relative Change:
T mean = +0.34
T min = +0.29
T max = +0.41
Now, if those results for Tmax and Tmin had been the other way around or at least equal to each other, you would have a good point. All it shows now is that more heat came in which simply has to linger longer. Do you get that?”
This is the RELATIVE CHANGE of the trend between these periods:
1958– 1985:
T mean = 0.036 (0.04)
T min = 0.11 (0.04)
T max =-0.04 (0.04)
DTR = -0.15 (0.01)
1985– 2002:
T mean = 0.38 (0.08)
T min = 0.40 (0.08)
T max = 0.37 (0.08)
DTR =-0.03 (0.02)
In both Tmin increases more than Tmax, a clear signature of greenhouse warming.
The “relative change” is the change in TREND (not temperatures) between those two periods. The Tmax trend increases more than Tmin trend because for Tmax the aerosol-induced cooling trend of 1958– 1985 switches to brightening+greenhouse induced warming trend of 1985– 2002, unlike Tmin, that show a warming trend in both periods.
Do you get that?
If you don’t I suggest you to read the article I linked:
“Impact of global dimming and brightening on global warming”
http://www.iac.ethz.ch/people/wild/2006GL028031.pdf
Henry@peru
http://www.arm.ac.uk/preprints/445.pdf
Here is a paper where you can see the actual data and where I know I can rely on its accuracy.
look carefully at fig. 8
There is no trend of rise in Tmin
Same for that station in Spain.
I will still find others, I will still get to the truth. Try to avoid showing me papers from East Anglia…or Virginia…
don’t you have one for Peru?
HenryP says:
January 6, 2011 at 7:36 pm
“Henry@peru
http://www.arm.ac.uk/preprints/445.pdf
Here is a paper where you can see the actual data and where I know I can rely on its accuracy. look carefully at fig. 8
There is no trend of rise in Tmin”
This is NOT what is shown in the paper, instead, it CONFIRMS (not refutes) the fact that minimum temperatures are warming faster than maximum temperatures, at least for this particular station.
The paper concludes:
“Long-term trends are seen in both seasonal and annual mean temperatures, with spring and summer series relatively flat compared with autumn and winter.”
(i.e. winter warming faster than summer. A greenhouse signature)
“Mean maximum and minimum temperatures show a consistent downward trend in the DTR at Armagh since readings began in 1843.”
That is, minimum temperatures (nighttime) warming faster than maximum temperatures (daytime). Another greenhouse signature.
That is, the results of this station are consistent with the global analysis in the paper “Impact of global dimming and brightening on global warming”
henry@peru
Did you not see that the trend in the TMin line is exactly the same as the trend of the Tmax line? How you get proof of GHG warming out of that one is a mystery to me.
if you want to quote, here is the conclusion:
In spite of the current warmer conditions, annual mean temperatures still remain within the range seen in the previous two centuries.
In the period of overlap, 1865–2002, we note that the features seen in the Armagh series are closely paralleled by features in the Northern Hemisphere mean temperature (Jones et al., 2001). The mid-19th century warm period, which is also seen in the central England series, has received relatively little attention.
It is important to establish the reality of such 19th century warmings, because that century is frequently used as a baseline for modelling the 20th century climate. A baseline at the end of the 19th century, when conditions were noticeably cooler, would exaggerate the subsequent warming in the 20th century.
I found some data here nearby in Pretoria, going back to 1973. We know that the dry months here are from May to September, so I am only going toput those data together.
Or would you say to rather look at the wet months?
I have analysed the data from this station here in Pretoria, South Africa
http://www.tutiempo.net/en/Climate/Pretoria/05-1974/682620.htm
for the month of May in every year from 1974 to 2010
(May is generally a dry month here in Pretoria )
Amazing results:
(pity it does not want to copy the graph out of excel here now)
The trend of the mean is absolutely flat
The (linear) trendline on maximum temps. is slightly up
The (linear) trendline of minimum temps. is slightly down.
So what does that tell you?
Unfortunately no global warming as a result of an increase in GHG where I live, I am afraid.
I did it again. All the results I find or get, always point to global warming due to reasons other than GHG warming. Like I said, the carbon dioxide is not your problem…
MORE CARBON DIOXIDE IS GOOD
Blessings,
Henry
WheelsOC wrote :
“From Peru: Thank you, but again I must clarify that the last data in the core study is from the year 1855, not 1905. The last bar on the graph is “95 years before present,” and in this data “present” is used in a paleoclimate convention to mean the year 1950, as with radiocarbon dating (Smokey might wish to take note so that he can avoid “amateur” mistakes). ”
Thank you for the correction WheelsOC.
I am not sure if there is any instrumental data dating back to 1855, but since Greenland was just getting out of the LIA at that time, I would be surprized if the temperature difference between 1855 to present would be less than than 2-4 C that Greenland experienced during the 1905 – present period.
Either way, this clearly shows, as “from Peru” already mentioned, that Easterbrook is “hiding the incline” at its worst. 2010 is likely to be the warmest in the Holocene, even in the cherry-picked location of Greenland.
For Henry:
You mention that you have 35 years of experience in Chemistry, but in your blog you fail to mention that a 30% increase in CO2 causes a (30%) increase in ocean acidification (Hydrogen ions) in the ocean. You only mention ‘outgassing’ of CO2 due to warmer oceans (which by the way assumes that warming is happening) and fail to mention that observations confirm ocean acidification consistent with our CO2 emissions.
Second, in you blog you mention a “CO2 cooling” effect due to the 5um CO2 absorption bands, but fail to mention that the sun does not radiate much energy in 5um, and on top of that, if CO2 would absorb that energy that it would cause warming of the troposphere (since CO2 absorbs in that band).
Now I’m sure that you “know what you are doing” as you state, but you did not provide any evidence to show that you are actually interested in doing science instead of politics.
Please update your blog with scientific evidence to your assertions (of CO2 cooling and ocean de-acidification), not to mention your remark that skepticalscience.com continues to “wipe your arguments away”. Until then, your reference to a recent FOIA by a “climate skeptics think tank” (American Tradition Institute) is very indicative of your motives and agenda. The truth is already out there.
Rob says
Either way, this clearly shows, as “from Peru” already mentioned, that Easterbrook is “hiding the incline” at its worst. 2010 is likely to be the warmest in the Holocene, even in the cherry-picked location of Greenland.
So Rob,
Are you not happy that it is warming?
Did you ever see a forest grow where it is very cold?
Don’t you like to see more more greenery?
I showed you that warming is not happening as a result of the CO2. That is clear from all the results I can find.
http://www.letterdash.com/HenryP/more-carbon-dioxide-is-ok-ok
Rob,
to all of your points,
1) All the results show it is warming, I did not dispute that. I say that it is not the carbon dioxide doing it.
2) If it is warming then the net effect will be that more CO2 is released from the oceans and the oceans will get less acid: H2CO3=>CO2 + H2O. This is good.
3) CO2 is not only cooling at between 4-5 but also has absorptions 1.6-2,3. Even some UV absorptions. Look how they are able to measure this radiation on earth as it bounces back from the moon. So it went from sun-earth-moon-earth. (see comments in my blog). And then how much is it cooling also because of photo synthesis?
4) I know what I am doing and I have proved it again in my previous posts here. Stay with Sceptical Science if the truth is not dear to you.
If this is your life’s work then I understand that you are disappointed. Unfortunately I cannot change the truth. There must be a reason God wanted me to investigate this.
I was like you, 100% with Al Gore. Now I feel a bit like Noah. Sorry, the flood about this hoax is going to come. Better be prepared.
Rob!
Did you read this?
http://wattsupwiththat.com/2010/12/28/2010%e2%80%94where-does-it-fit-in-the-warmest-year-list/#comment-568188
Henry,
Thank you for making my point.
henry@Rob
why then do you keep coming back to
wattsupwiththat?
I just finished reading this very interesting article by Dr. Easterbrook. His charts show very clearly that these temperatures have happened before over and over.
Many thanks to Dr. Anthony Watts for bringing so many scientists to a much wider audience. This is by far the best site for climate discussion. It’s so essential that I’ve already set WUWT as my home page!
I have a stupid question about ice core analysis. Looking down through the layers, is it possible to pick up the condition whereby warming was so large for a given period that it completely melted away snow from those years and is therefore not there to be counted?
@HenryP: So, you say that J. Storrs Hall was also wrong by asserting that things have been a lot warmer in the past and that the current warming ‘hockey stick’ is dinky compared to what happened in history?
Having read over that post, yes it seems he is making much of the same mistakes as Dr. Easterbrook (even getting the dates wrong, as Nick Stokes and Willis Escherbach point out in the comments). Not only did he describe (what he though was) 1905’s temperatures as “today’s”, he even forgot to take into account that “years before present” is “years before 1950.”
I’m left wondering why actual paleoclimate people aren’t being sought to make posts that explain Greenland’s temperature history for the benefit WUWT readers, instead of having a retired geologist and a nanotechnologist both make guest posts here, and both get it very wrong (in much the same way, even). In fact, since these very same errors have been pointed out repeatedly before, why isn’t Anthony discussing it with the authors or in the comments?
In addition, Hall totally leaves out a graph of the modern warming trend as revealed by the instrumental data instead of giving both sets of data a graphical comparison. If he wants to say that the current “hockey stick” is not unprecedented, he may want to actually work with the graphs and show it.
Henry@WheelsOC, Rob, etc.
I think you people might find this investigation done by myself interesting!?
http://letterdash.com/HenryP/assessment-of-global-warming-and-global-warming-caused-by-greenhouse-forcings-in-pretoria-south-africa
You too can do this! It is easy. Prove it for yourself that it is not warming.
Smokey, light up another cigar there!
Henry@Rob
I have been through my posts and I definitely cannot see where I said something political that could possibly described me as being “rightwing”
I am actually more socialist, because I see Jesus was like that, as seen by the actions of his followers, Acts 4:32-35
I’d love to hear what you think of the rsults of my investigations, here,
http://letterdash.com/HenryP/assessment-of-global-warming-and-global-warming-caused-by-greenhouse-forcings-in-pretoria-south-africa
Well Henry, I didn’t realize the weather in Pretoria, South Africa = global average temperature, or that 1 weather station > 7,000 globally-distributed stations. This, of course, changes everything.
I mean, if the climate has been basically the same for that one station in Pretoria, South Africa for the last 36 years, clearly the other 99.9999999999999% of the globe follows suit. It’s all so clear to me, now. Thank you for showing me the error of my ways.
Henry@Wheelsoff
It appears you have not read the report until the end!
Did you understand what I did?
Clouds are important. it is all in the clouds.
if more heat comes to earth then you get more clouds and that brings everything back to zero.
So what we call “weather” is really God’s way of keeping the temperature of our planet stable.
Otherwise we’d all melt in the heat or be frozen in the cold.
But if you want to see if global warming is happening my thinking was that you must eliminate those clouds
and “weather” in general
because they are going to cause serious scattering, especially if it occurs at night in winter.
The results you get, will then become dependant on how long those clouds linger,
which, from one day when compared to the same day (on the calendar) exactly one year ago, may be very much different,
if your place of measurement on earth is constant.
I was expecting you to come up with your weather stations comparing dry and cloudless days – during the past 50 years when we had this enormous increase in CO2 but obviously you are not interested in finding out what the truth is in your own area.
In the meantime, the trees and the plants have been talking to me. They all said they want more warmth and more food (carbon dioxide)
So who is the real man standing up for the environment?
HenryP said :
“I have been through my posts and I definitely cannot see where I said something political that could possibly described me as being “rightwing” “.
Not surprising Henry, because I never suggested that you are “rightwing”. So you made that up all by yourself. I did however suggest that you “update your blog with scientific evidence to your assertions (of CO2 cooling and ocean de-acidification)”, which you have not done yet.
HenryP said: “the trees and the plants have been talking to me”. That’s very nice Henry, but maybe you could sustain that perception with some scientific evidence as to the response of trees and plants to our CO2/methane emissions, forest destruction and land-use changes. I’m sure you will find (as most biologists do) that trees in the real world experience more severe constraints than CO2 limits. For example, you will find that CO2 increases enables weeds to grow more vigerously, while trees suffer due to water constraints. And that changes in the climate and aquatic environment cause annihilation of a massive amount of species that cannot adapt to the rapid changes we are imposing on them. So much that biologists are already naming our era as the “Holocene extinction event”.
We should realize that science is the ONLY objective method by which we can judge our own actions. So get the science right at the very least…. Please adjust your blog.
I share your faith in God, and the responsibility of humans to take care of all creatures that share this planet with us. But what I see is that our actions (including burning millions of years worth of fossil fuels) is seriously disrupting to our planet’s eco systems and is already causing great stress on this planet’s living species, including record numbers of extinctions. Not to mention the damage that we will cause when our carbon emissions will increase uncontrollably.
It is time that we face our responsibility as expressed in every major religion that we hold, and minimize the harm that we impose on all the millions of species that share this planet with us. Time to show our children and grandchildren that we stand by our belief that we are the caretakers of this planet, and not the undertakers.
Rob,
surely you must agree now to my conclusion that the Co2 has nothing to do with the warming of earth?
That is what my all my 3 samples proves. South Africa, Spain, Northern Ireland.
It cannot be a co-incidence. They all say the same thing. The minimum temps. do not show an increase in line with modern warming.
http://letterdash.com/HenryP/assessment-of-global-warming-and-global-warming-caused-by-greenhouse-forcings-in-pretoria-south-africa
In addition, it appears that warming has stalled. Pity.
I have had two kids, and when they were small they were quickly able to communicate to me if they wanted warmth, food or love
Now I have two dogs, and somehow they are also able to do exactly the same.
yesterday, the plants and trees in the garden talked to me.
They said they really wanted more warmth and more food (carbon dioxide)
but now we have thousands and thousands of people including yourself who believe
– or who have been made to believe \ (brainwashed) –
that global warming and carbon dioxide is bad
So I am the only one, really, and a few here at WUWT, who is standing up for the environment.
Don’t think that you can continue to lie about the goodness of the carbon dioxide for the environment and the grace of God for you will just continue to increase to cover the sin of speaking untruths. It does not work that way.
Obviously I am for the environment and everything. We need more living space for animals. We need to take a stand against people taking the habitats of the animals.
BTW, do you know what caused the glacier in Kilimanjaro to retreat? Unfortunately, this is Africa and here they just cut the wood of the trees if they need to cook or get warm. Do you think that is better than coal? I think it is better to give them electricity from gas or coal and then filter out the sulphurs and heavy metals?
(3rd generation power stations)
this is an important debate for AFRICA and INDIA, you must tell them that it is OK to put more CO2 in the air.
God bless you
if you do
“1934 has long been considered the warmest year of the past century.”
Umm, 1934 was the warmest year in the continental United States. Not on the planet.
Climate science reports average global temeratures. Land and Ocean. Over the whole planet. The United States is , what, 5% of the earth’s surface? It’s not a measure of average global temperature trends. Most warming, as I understand it, occurs over ocean regions and polar regions.
HI Peter
yes we are asking people to check their local weather station (where they live) to see if it has been warming over the past 30-50 years when we had this massive increase in the carbon dioxide. In my home town mean temps. have not changed and minimum temps. have been decreasing which refutes the theory of global warming being due to an increase in GHG’s
here is my report:
http://letterdash.com/HenryP/assessment-of-global-warming-and-global-warming-caused-by-greenhouse-forcings-in-pretoria-south-africa
So we are all here agreed now that more carbon dioxide is good for the environment as it stimulates growth (forest and greenery).
Greetings. Unfortunately, I’ve never heard of “letterdash.com”.
I haven’t heard of the U.S. National Oceanographic and Atmospheric Administration, NASA, a plethora of other highly reputable scientific organizations with umimpeachable credibility. Every single one of them says there’s a global trend upward in temperatures. Every reputable scientific organization on the planet acknowledges that pumping more carbon dioxide in the atmosphere will – with a high degree of scientific certainty = affect climate and temperature – sometimes in good ways, as you suggest, but mostly in bad ways.
Asking anonymous people on the internets to check their local weather stations is hardly sound science. Gathering and analyzing representative data on regional trends takes an effort by trained people and an extraordinary amount of rigourous technical work. Otherwise, we wouldn’t need to train people for eight to ten years in college to do scientific work. Do anonymous people on the internets know how to do trend analysis, and rigorous study in accordance with established scientific methodology.
Its not plausible that Global climate and global temperature trends can be scientifically analyzed posting some website nobody’s every heard of, and asking untrained people to look at some local weather stations. That’s not science.
Well Peter X(?) if you had read and understood my report you would have figured out that there is something worrying about it, but it is opposite as of what you think it is or should be. If you can figure out what worries me about my own report you are a genius.
In the meantime, there is confimation of my observation that GHG’s do not cause warming, first of all when you look at my own summary of all of my investigations,
http://letterdash.com/HenryP/more-carbon-dioxide-is-ok-ok
(note that South-Africa< Spain < Northern Ireland are on one line covering the whole of earth and minimum temps. have not been increasing here in line with modern warming)
but there was also a lot of it here on WUWT. I suggest you keep up to date with it, so it won't hit you one day like Noah's flood did to most of compatriots.