Global Warming and the Posture of Skepticism

I couldn't believe my eyes when I saw it. There was my latest issue of Skeptical Inquirer magazine – the “Magazine for Science and Reason” – and on the cover were the words:

“Let's Cool It on Global Warming–Bjorn Lomborg.”

I was stunned.

I started my professional career working for Skeptical Inquirer. My last book was excerpted there, and I'm currently a contributing editor.

Typically, the magazine debunks real nonsense–pseudoscience, claims about the paranormal, quack UFO visions, that kind of thing. And I'm totally with them: Crop circles are a prank, there's no Bigfoot or Nessie, and that untested herbal remedy you're taking might well be dangerous.

And yes: The face on Mars is just an interesting rock formation.

So what on earth was Skeptical Inquirer doing publishing someone like Lomborg–who, as I have shown here at DeSmogBlog, and as others have shown elsewhere, remains scientifically inaccurate when it comes to discussing the real risks posed by global warming?

Lomborg consistently–and irresponsibly–downplays the worst case scenarios that we have to worry about if we just continue to unrepentantly pollute the atmosphere with heat-trapping gases. And sure enough, here he is doing it in Skeptical Inquirer, right at the outset of his article:

Man-made climate change is certainly a problem, but it is categorically not the end of the world. Take the rise in sea levels as one example of how the volume of screaming is unmatched by the facts. In its 2007 report, the United Nations estimates that sea levels will rise about a foot over the remainder of the century. While this is not a trivial amount, it is also important to realize that it is not unknown to mankind: since 1860 we have experienced a sea level rise of about a foot without major disruptions…We dealt with rising sea levels in the past century, and we will continue to do so in this century. It will be problematic, but it is incorrect to posit the rise as the end of civilization.”

This is claimed by Lomborg and Skeptical Inquirer to be the approach supported by “facts and reason.

But in fact, it's nothing of the sort.

First of all, it's not like we can suddenly stop worrying about sea level rise after the year 2100. Furthermore, the United Nations estimate cited by Lomborg is being outrageously misused. That UN report (PDF) fully admitted that its sea level rise projections for the year 2100 do not include “rapid dynamical changes in ice flow.”

Which, of course, is what everyone is really afraid of.

Here's the glaringly obvious and completely terrifying fact: If we don't do anything about global warming, if we just let it rip, we run the risk of eventually (no one knows exactly when) destabilizing the Greenland and West Antarctic ice sheets. And if these fall in the ocean we're talking about a sea level rise of many feet, not inches, and the resultant loss of major coastal cities, like New York.

How do we know this? Well, in a part that Lomborg doesn't cite, the self-same United Nations report explains: “The last time the polar regions were significantly warmer than present for an extended period (about 125,000 years ago), reductions in polar ice volume led to 4 to 6 m of sea level rise.”

That's the world we're heading back to if we don't alter course quickly. In ignoring this fact, in simply pretending that all we have to do is worry about an inch of sea level rise, Lomborg is disqualifying himself from being taken seriously.

So what on earth is Skeptical Inquirer doing publishing him?

I think several things are going on here. One is simply that Lomborg employs the rhetoric of “science and reason” even as he actually abandons both. But alas, for someone who doesn't really know anything about global warming yet prides him or herself for supporting critical thinking, Lomborg might sound convincing.

Still, Skeptical Inquirer certainly ought to know that not everyone who claims to have science on his or her side actually does. Anti-evolutionists claim the support of science. So did tobacco companies. Indeed, they helped spin off an entire “sound science/junk science” movement that is basically dedicated to calling good science bad and bad science good.

But I think something else is going on here as well, far beyond naievete. A few issues back, Skeptical Inquirer published a very respectable two-part series of articles by Stuart Jordan laying out the mainstream scientific position on global warming (see here).

This was all to the good.

But perhaps in part because the organized “skeptic” movement in the US has so many overlaps with global warming denying free-market libertarianism–for complex reasons that I can't really address here–Jordan's articles caused a Skeptical Inquirer reader uproar, leading to several further responses from the author (see for example here).

And now, suddenly, we find Skeptical Inquirer publishing Lomborg.

I really support Skeptical Inquirer. I want it to do well. But to preserve credibility, it needs to cast aside the skeptic-libertarian readers who simply refuse to accept the overwhelming reality of global warming.

In this sense, publishing Bjorn Lomborg–whose claim to the mantle of science and reason cannot possibly be sustained–was a huge step backward.


In John Cook’s words (

“Scientific skepticism is a healthy thing. Scientists should always challenge themselves to expand their knowledge, improve their understanding and refine their theories. Yet this isn’t what happens in global warming skepticism. Skeptics vigorously criticise any evidence that supports anthropogenic global warming (AGW) and yet eagerly, even blindly embrace any argument, op-ed piece, blog, study or 15 year old that refutes AGW.”

Time to “get skeptical about the skeptics”, so to speak. Show the “skeptics” for who they are.

Frank Bi,

Time to “get skeptical about the skeptics”, so to speak. Show the “skeptics” for who they are.

Good idea. I sooo agree. They should be recognized for being the only remaining intellegent people left.

Bjorn Lomborg is such a refreshing voice or reason in a sea of alarmist nutbars.

Bjorn Lomborg is guilty of heresy against doctrine.
Nothing more.
He has the courage to be honest in the face of religrous dogma.

The “skeptics” are so “skeptical” that they just keep repeating mantras.

All the peer-reviewed work by climate scientists all over the world is summarily dismissed as “religrous [sic] dogma”. And a silly book by Lomborg which argues that polar bears can evolve like Pokemon is touted as the “voice or [sic] reason”.

Again, that’s AGW “skepticism” for ya.

Frank Bi,

“Bjorn Lomborg is guilty of flawed statistical analysis that the Danish scientific community rejected his analysis.”

“Q: Wasn’t Bjorn Lomborg proved scientifically dishonest?
A: No. Using a critique written by Lomborg’s critics in the Scientific American (January 2002), the Danish Committee on Scientific Dishonesty (DCSD) found that The Skeptical Environmentalist was objectively scientifically dishonest on January 7 2003. However, on December 17 2003, the Danish Ministry of Science, Technology and Innovation completely rescinded this finding. It released a 70-page evaluation criticizing at least 13 points in the DCSD report, three of which individually would have led to it being rescinded.

It found the DCSD verdict “dissatisfactory”, “deserving [of] criticism” and “emotional.” Most importantly, the Ministry found “that the DCSD has not documented where [Lomborg] has allegedly been biased in his choice of data and in his argumentation, and that the [DCSD] ruling is completely void of argumentation.” The case was finally dropped by DCSD March 12 2004.

While Lomborg’s critics continue to quote the DCSD’s 2003 verdict, it has been rescinded and found to be “dissatisfactory,” “emotional” and “completely void of argumentation.” An independent Dutch group of scientists analyzed the DCSD verdict and found that the comittee “delivered an almost totally political verdict.”

If Lomborg says Lomborg isn’t dishonest, then it must be true!

Goes to show once more the high degree of “skepticism” being exercised by the “skeptics”.

Frank Bi,

“If Lomborg says Lomborg isn’t dishonest, then it must be true!”

What if the Danish government says so? – Since, uh, that’s who actually said it.

And Frank, don’t you think it would be fair to let the other residents of your group home have a chance to play with the computer, too?

“don’t you think it would be fair to let the other residents of your group home have a chance to play with the computer, too?”

Is there a scientific argument here?

More “skepticism” in action, I see.

Frank Bi,

I will agree though, the original DCSD was invalidated, and there was no follow up claim.

Doesn’t mean he’s right. Just means the original argument against him was sloppy.


That said
Lomborg is simply wrong, Here’s why, in detail:

“Doesn’t mean he’s right. Just means the original argument against him was sloppy.”

Yes, if by “sloppy”, you actually mean fallacious, and hence, completely unsuccessful. Not unlike the subsequent arguments.

But then, sloppy seems to be a theme with AGW enthusiasts:

You meant _this_, rob?

(discussed below)

Frank Bi,

True scientists are naturally skeptical especially when there’s a political agenda lurking largely in the background.

Just when the looney lefties thought they had successfully pushed the new religion of Gorebal Warming firmly down our throats comes a shocking report…

Yes, believe it or not, the earth is not getting warmer any longer, in fact it’s cooling down, and fast! Unless Gulfstream Gore can figure out a way to blame the precipitous drop in global temperatures over the last twelve months on increased CO2 levels, he’ll have to find another way to raise taxes on corporations other than his ridiculous Cap and Trade idea or similar proposals. Proposals which, by the way, result in all of us paying more for everything we buy and consume and give our oversized government even more control over our lives.

Here’s the scoop. The four major temperature tracking organizations report a .75C drop over the last twelve months; almost enough to wipe out the entire warming of the past 100 years claimed by Climate Fanatics. Check out the link below for details. This should be good news, but if the trend continues we could be headed for another Little Ice Age. Remember the TV drama The Day After Tomorrow? It’s not a pretty picture as the US is completely covered by an ice sheet and Americans become illegal aliens as they flee for their lives to Mexico! Yes, as difficult as it might be to accept, we may have no choice but to drive even bigger SUV’s, burn more coal and oil, and fly around the world more often on vacation in hopes that increasing CO2 levels might warm our freezing planet enough to save humankind from extinction.

So what’s next? Will the Old York Times report this as the big news item that it is, or will it be buried on page 39b? Will CNN’s Wolf Blitzkrieg bring this to the forefront at prime time or somehow just fail to report it at all? Will schools that have been making kids watch Gore’s deliberately deceptive “Scary Movie” both here and abroad remove it from their curriculum and have to apologize to students and parents for teaching falsehoods based on pseudo science? Will Gore create an even stranger new religion that taxes ice cubes? We will have to wait and see, but in the meantime there’s one really cool event that I can’t wait to see……

The sweetest moment of all will be when Gore is forced kicking and screaming to give back his Nobel Prize!


Yet another so-called “skeptic” who enthusiastically embraces some half-baked argument without even making the slightest effort to check the facts.

Guess what, I debunked this silly “proof” you quoted just yesterday:

Executive summary:

What the DailyTech “proof” tried to do is to take two data points, draw a straight line, and call it a “global cooling” trend. Yeah, great.

The nice thing is, the same method was used back in 2006 to “prove” that global warming came to an end in 1998. Of course, that didn’t happen, which is why our denialists now have to adjust the “end date” and “prove” that global warming came to an end in 2007.

Anyone wants to bet our denialist friends won’t adjust the “end date” again?

(But hey, why should a “skeptic” care? After all, “skepticism” is about mindlessly regurgitating every piece of denialist “news” that comes along, no? By the way, the link to John Cook I quoted is up against precisely this rubbish.)

Frank Bi,

I eagerly followed your links to where you claim to have “debunked” the recent calculations of declining global temperature, and all that I found was a two-years-old essay in which you debated (not debunked) Carter’s conclusions. That’s false advertising.

Who (other than you) interprets Watts’, summary to mean that “global warming stopped in 2007”? An unbiased reader would see only that temperature is currently declining much more rapidly than in the previous 8 years, but there is no suggestion of a hiatis. For the last decade, the trend has been undeniably downward, and one doesn’t have to start graphing from the tip of the 1998 peak to get that result. Do a simple equal areas projection for 1998- 2007 and the trend line slopes downward to the right. Period. The end. Full stop. Whether or not that is significant is a matter for debate but, you scupper your credibility when you pretend that it hasn’t been happening.

ZOG, where do you get your misinformation from? Do you make it up yourself or do you spend too much time on the denier web sites? Why not spend some time actually reading up on the science of climate change. there are a number of easily accessible web sites which give a very good background in the science.

As I showed another of the neuronally-challenged trolls a few months ago, the data DO NOT SHOW A DECLINE IN TEMPERATURE OVER THE PAST 9 TO 10 YEARS.

Here are the most recent data from GISS (Dec - Nov numbers)

1995 - 0.46
1996 - 0.38
1997 - 0.40
1998 - 0.70
1999 - 0.49
2000 - 0.42
2001 - 0.54
2002 - 0.70
2003 - 0.65
2004 - 0.61
2005 - 0.75
2006 - 0.65
2007 - 0.75

The right hand column shows temp anomaly in degrees C based on the 1951-1980 average.

Then I did a series of regressions to give the slope of temperature change over a number of yearly ranges:

1995-2007 - 0.026
1996-2007 - 0.028
1997-2007 - 0.026
1998-2007 - 0.020
1999-2007 - 0.034
2000-2007 - 0.035

Right hand column represents the rate of change of temperature in degrees C for the given period (slope of the linear regression line). No matter which year you pick as a starting year the slopes are all positive, indicating RISING TEMPERATURES.

How can anyone with even the lowest level of statistics say that temperatures have remained constant over the past 9 - 10 years, let alone say that they have dropped? For anyone who claims to be “an expert in statistics”, (M, M and W) it shows that they are liars.

So do us all a favour and stop repeating the nonsense that global warming stopped in 1998, 2000, (take any year you want it still won’t work).

Ian Forrester

Clearly Zog got his info from denialist sites; you can tell because he chose 1998, that unusually hot year because of El Nino, for his end date; and 2007 with its colder La Nina winter for the other end date.

VJ, I guess that you missed this sentence in my original post: “For the last decade, the trend has been undeniably downward, and one doesn’t have to start graphing from the tip of the 1998 peak to get that result.”

Not that it matters a damn, since several of your previous posts ranting about evil, greed-driven corporations have established that your only interest in the GW debate is a burning elitist desire to dismantle society - for the greater good of course.

I’m guessing that you’re quite young, and your 1960s rhetoric doesn’t fit too well in 2008. Where did you pick it up? Mummy and Daddy? A hippy professor? Just wonderin’.

hey Ian.
Do a little background reading on Hansen’s now famous Fudging.
GISS data is about as acurate as licking you finger and sticking it out the window.
He manipulates old temperatures down and new ones up to propogate his myth.
What incredible noncense.
Only devout cultists trust anything out of GISS anymore.


Try this. Go to
and plot the global monthly temperature anomaly from January 2001 through January 2008. Then plot a linear regression line through that data. Observe the zero slope. (Technically it’s slightly negative, but approximately zero.)

No one denies that the earth was warming slightly from the 70’s through 2000. However, since then, there has been no global warming, even though CO2 levels have continued to slowly increase. It will be interesting to see if the recent cooldown in global temperatures continues. I, for one, hope not since a global cooldown to Little Ice Age levels would likely be much more devastating than the slight warmup we were seeing throughout the 80’s and 90’s.

Of course. The difference is that the satellite data is likely quite a bit more accurate. Regardless, do the same thing with the GISS data. Go to and graph the monthly global temperature anomaly from January 2001 through January 2008. Plot a linear regression line through the data and notice the slope of zero. (OK, technically a very slight positive slope, but essentially zero.)

Ian - of the available data sets for the period in question, you have arbitrarily referred only to the one which is least reliable and which, coincidently, shows the greatest warming. Now why would you do that, I wonder?

The accuracy of raw GISS inputs is well outside of the range of temperature variations being measured, i.e., they aren’t significant numbers. NASA (Hansen et. al.) attempts to correct the deficiencies by applying undefined “corrections”. Not too many years ago, handling empirical data like that was known as “cooking”.

Satellite measurements of lower troposphere temperatures by microwave sounding units (MRUs) aren’t perfect either but, at least they aren’t subject to gross human errors in sensor location, they deliver consistent records over land, sea and ice, and they are much less susceptible than land-based stations to heat island effects. In other words, they are late 20th and early 21st century technology.

GISS and the slightly more reliable Hadley CRUT data are still derived from obsolete technology incorporating huge scope for human error.

GISS, HadCRUT and MSU all show a rising temperature trend from 1979 to 2008 but, from 1998 onward (the time interval that we are discussing), the GISS trend is, as you calculated, gently rising, and the trend from the more reliable satellite data is downward at about 0.12°C/decade.

In absolute terms, the plotted GISS temperature anomaly for the period 1979 to 2008 is roughly 0.2°C larger than that obtained from MRU. Within the range of variability under consideration, that is one hell of a big number! The HadCRUT curve falls about halfway between the GISS and MRU curves. Interestingly, the three data sets converge at the 1998 el Niño and current la Niña events. Damned if I can figure out why.

Ian, your snotty first paragraph is quite typical of your Neanderthal approach to anything related to scholarship, and your selective presentation only of data supportive of your cause is downright deceitful. Unfortunately, even some senior warmists (eg. Mann, Hansen) aren’t averse to using such tactics when it suits their purpose, so I guess that you’re a good disciple.

Actually Zog, if you re-range the GISS data to use a 1979-1998 zero-point mean (the same year span used by the satellite data for their mean), you will see that you will end up shifting the GISS data downward by about .24 deg C. It then matches up more closely with the satellite data. The GISS team uses a 1951-1980 mean to define the zero-point for their temperature anomalies. The GISS data just looks warmer because the 1951-1980 years were on average slightly colder than the 1979-1998 years. I’m sure it’s just coincidence that the GISS team chose a cooler zero-point for their anomaly numbers.

“The GISS team uses a 1951-1980 mean to define the zero-point for their temperature anomalies.”

“I’m sure it’s just coincidence that the GISS team chose a cooler zero-point for their anomaly numbers.”

Thanks Keith. I should have tumbled to that.

Your answers are just a load of rubbish. It does not matter what you take as your baseline since we are discussing trends not absolute values. Read some basic maths and physics then come back and discuss it.

You also missed the other major reason why GISS is more representative of GLOBAL warming.

If you don’t understand what GLOBAL means then you are even more ignorant than I thought.

Ian Forrester

O.K., Ian, now you can quit grunting and snuffling, put your knuckles back on the ground and shuffle back into your cave. Maybe someday you’ll learn to communicate with civilized people. Some warmists have mastered the art.

And speaking of communication - of course the important issue is the downward TREND of global temperature - not the absolute values. Try reading my post again, if that doesn’t make your lips sore.

“You also missed the other major reason why GISS is more representative of GLOBAL warming.” Did I now?

The reason that it is representative of global warming is that it’s an artificial construct tweaked (sorry, “corrected”) to fit the theory. The juggling of data to yield a desired result is an affront to science and a public disgrace.

It’s ignorant trolls like you that I get upset with.

Why don’t you come out from behind your ridiculous name and tell us who you really are and then slander Dr. Hansen? If you are so sure of your “facts” then you would not need to hide, that is a sign of an ignorant coward.

By the way the reason GISS is better for GLOBAL temperatures is that RSS doesn’t go poleward of about 80 degrees. Thus it omits the areas of the GLOBE with the highest amount of warming.

You are one ignorant and disgusting person.

Ian Forrester

And there are, at most, about a dozen permanent surface stations “poleward” of 80°. You should stick to biotech, at which you are such an enormous success (sarc off).

Ian Forrester impotently raged:

“Why not identify yourself like a man would?”

Hmm, not a very prudent idea, given that there are psychotic snap-jobs who collect guns, like Ian Forrester, out there.

Ian, did you bother to download the GISS data and plot it? If you need help understanding how to use Excel, just let me know, and I’d be happy to lead you through how to do it. Please do this and at least look at the point I was trying to make before you start slinging ad hominem attacks in my direction.

Do you think I just made up these numbers? You are as silly as your troll friend ZOG.

You are the ones using ad hominem attacks, not me. If you act in a stupid, ignorant and demeaning manner I will respond, but it is not an ad hominem attack merely showing you the truth about yourselves.

Ian Forrester

Ian, so you agree that according to the GISS data there has been no warming for the last seven years (Jan. 2001 through Jan2008)?

No, I don’t agree with your conclusion that “according to the GISS data there has been no warming for the last seven years (Jan. 2001 through Jan2008)”.

A linear regression of the data I presented above for temperature anomalies between 2001 and 2007 show an INCREASING TREND OF 0.0225 degrees C per year.

Are you just being stupid on purpose or do you truly not understand how temperature trends are calculated?

If I have made any error I would welcome you pointing it out to me but I believe that what I have done is correct.

Ian Forrester

Ian, no offense, but I have no interest in data you posted without any links for me to verify its veracity and context. I’m using data directly from GISS’s monthly update site at:

Please do the same, and plot the monthly global anomaly data from January 2001 through January 2008. Please tell me if the slope of a linear regression trend line through this data is not approximately zero. To do this, create a chart with your data, right click on the trend line, and select Add Trendline…

Mmmmm seems to be the same data you used so how come you get “approximately zero”?

I used the D-N data since I did the original analysis in December.

I stand by my conclusion that the temp trend for 2001 to 2007 is 0.0225 degrees C per year.

If you plot the monthly temps you get a slightly lower value but these numbers are not “approximately zero.”

Ian Forrester

I’m starting to wonder now if “approximately zero” is just a sneaky way of saying “not zero”.

Frank Bi,

Ian, thanks for the link to your data. It helps to understand the discrepancy. Your link only includes land-based meteorological stations and does not include sea surface temperatures as the link I gave you does. You are correct that a plot of monthly temperatures from the land-only data from Jan. 2001 through Jan. 2008 has a positive linear regression slope, but for that time span, it is only about .013 deg C per year. For the land plus sea surface temperature data from GISS, the slope is about .005 deg C per year. I consider .005 deg C per year to be essentially zero considering the magnitude of error in the measurements themselves.

As an aside, I so wish I had Excel when I was in college! Compiling lab results would have taken 1/10th the time.

I can now see where your selection of data gives a lower increasing trend than the set I chose. However, neither set gives credence to those who claim global warming stopped in 1998, 2001 or any date they care to choose. The rate of increase has slowed a bit but it is still increasing.

Nowhere in the science does it claim that the increase in temperature should be linear. There are a number of factors which determine global temperature though CO2 is still the main driver.

Ian Forrester

Ian, I guess we’ll have to agree to disagree. The GISS data over the time period Jan. 2001 through Jan. 2008 shows .005 deg C per year of warming. I claim this to be essentially zero, while you claim this to be significant enough to be called an increase. The satellite data, which I’ve already stated I believe to be more accurate, shows .004 deg C per year of cooling over the same time period. However, I make no claim that this is significant, but rather once again a data point showing essentially zero change for the past 7 years.

Regardless, thank you for eventually participating in a rational, intelligent discussion. I wish more of these type of discussions could take place online between people who disagree without the mindless vitriol from both sides.

Keith, you’d believe satellite data over actual instrumental data? That’s a sign of poor judgment and is similar to if one were to try and guess the weight of someone based on their height and their appearance rather than to get them to stand on a scale and actually measure their weight.

Satellites derive temperatures and are not necessarily accurate. Instruments (i.e. thermometers) actually measure the temperature.

Stephen, satellites use an instrument called a Microwave Sounder Unit to convert microwave radiation measurement into a temperature.

Ground stations use an instrument called a thermocouple to convert a millivoltage produced by a junction of two dissimilar metals into a temperature, or an instrument called a thermistor or an RTD to convert a resistance measurement into a temperature.

All of these temperature measurement methods have the capability for errors due to inaccurate calibration or various inaccuracies in the measurement of the variables themselves.

Based on your comment, I must assume that you do not understand how temperature is measured. Somehow, however, you feel qualified to accuse me of poor judgement. Must all of these discussions start with attacks?

There is a vast difference between actual thermometers, whether they be mercury in glass, thermistors or any other form of thermometer than MSU. The biggest difference is that thermometers are actually calibrated before they are distributed. They can be re-calibrated any number of times during use to ensure that they are not drifting.

The MSU’s do not measure temperature directly but “they measure radiances in various wavelength bands, which must then be mathematically inverted to obtain indirect inferences of temperature” (

Thus there is a wide distribution of thoughts on the actual mathematical conversions to be used (Spencer and Christy even managed to get simple errors included in their original transformation).

Thus it is a big stretch of the imagination to suggest that the satellite measurements are “more accurate” than readings from real thermometers.

There have been numerous errors found and corrected in the readings and conversions of the MSU data.

The reasons that MSU temperatures are considered more accurate by the deniers is that the original data by Christy and Spencer showed very low temps compared with ground measurements. Thus they (AGW deniers) jumped on the bandwagon that “AGW has been disproved”. Unfortunately for them the errors in the measurements were found and now the MSU data and land based measurements are in good agreement.

However, the damage has been done and deniers still believe the original results of Christy and Spencer. I often wonder would would have happened to MSU data if Christy and Spencer’s error had been in the other direction, i.e. had resulted in much warmer temps.

Ian Forrester

The MSU instruments are routinely calibrated as described here:

I have not been able to find documentation on how often the MMTS sensors used by the majority of the ground stations are calibrated. If you have a link to this, I would be interested in seeing it.

The ground stations also do not measure temperature directly. They generally rely on a thermistor which measures resistance. This resistance is then mathematically converted to a temperature.

I agree with you, Ian, that the temperatures measured by satellite and the temperatures measured by land instruments are generally in close agreement. My problem with the land instrument record is that it is subject to many more subjective interpretations such as instrument location, urban heat island effect, etc. To the GISS team’s credit, they seem to be doing a decent job of correcting for these effects such that their post-1979 data is in relatively close agreement with the satellite data.

One area I’ve been trying to research is how the GISS corrections to land-based data have changed data values prior to 1979. Do you happen to know of any GISS websites which show global temperature anomaly estimates both prior and after the corrections they now apply? I’ve been able to find this for individual stations, but not for the global estimate.