New items are added occasionally to the lists of related reading and related posts at the bottom of this page.
The GISS set comprises surface thermometer records going back to January 1880. It takes a lot a massaging to construct a monthly time series of “global” temperatures that spans 137 years, with spotty coverage of Earth’s surface (even now), and wide variability in site conditions, among other problems that can occur in a not-truly-global or systematically controlled network of thermometers over the span of 137 years. There’s the further issue of data manipulation, the most recent example of which was the erasure of the pause that had lasted for almost 19 years.
The UAH database goes back to December 1978, and consists of readings obtained by a system of satellites. A satellite-based system has obvious advantages over a surface-based system, if one’s objective is to obtain accurate and consistent estimates of Earth’s atmospheric temperature.
There are other databases, including those produced by RSS (satellite-based) and HadCRUT (surface-based). But the point of this post is to compare GISS records with those a satellite-based system, and I have chosen the GISS and UAH systems for that purpose.
In Figure 1 you can see that despite efforts to hide the decline — a cooling trend from about 1940 to the late 1970s — GISS could only muster a long pause in the rise of its global temperature estimates.
(I used December 1978 as the “zero” point for ease of comparison with Figure 2.)
Now look at UAH vs. GISS for the span covered by UAH, namely, December 1978 to the present:
The pause, according to RSS, extended from February 1997 to November 2015. This agrees with the UAH data for that period, which show a flat trend; whereas, the GISS data for that period show a rising trend. Taking the UAH slope as the correct one, it seems that GISS overstates the slope of the pause by 0.0011 degree C per month. Subtracting that overstatement from the GISS coefficient for the entire period gives a new GISS slope of 0.0007 degree C per month, which is close to the UAH slope of 0.001 degree C per month. It is also the same as the GISS slope for 1880-1937 (see Figure 1).
I therefore conclude the following: GISS has been doctored not only to hide the decline from about 1940 to the late 1970s and the pause from 1997 to 2015, but also to exaggerate the rise from the late 1970s to the present.
What is really going on? The recent rise in temperature has been ripped out of context. This is from a post by Dr. Tim Ball (figures re-numbered to avoid confusion):
Recent discussion about record weather events, such as the warmest year on record, is a totally misleading and scientifically useless exercise. This is especially true when restricted to the instrumental record that covers about 25% of the globe for at most 120 years. The age of the Earth is approximately 4.54 billion years, so the sample size is 0.000002643172%. Discussing the significance of anything in a 120-year record plays directly into the hands of those trying to say that the last 120-years climate is abnormal and all due to human activity. It is done purely for political propaganda, to narrow people’s attention and to generate fear.
The misdirection is based on the false assumption that only a few variables and mechanisms are important in climate change, and they remain constant over the 4.54 billion years. It began with the assumption of the solar constant from the Sun that astronomers define as a medium-sized variable star. The AGW proponents successfully got the world focused on CO2 [emphasis added], which is just 0.04% of the total atmospheric gases and varies considerably spatially and temporally…. [I]t is like determining the character, structure, and behavior of a human by measuring one wart on the left arm. In fact, they are only looking at one cell of that wart….
Two major themes of the AGW claims are that temperature change is greater and more rapid than at any time in the past. This is false, as a cursory look at any longer record demonstrates…. The Antarctic and Greenland ice core records both illustrate the extent of temperature change in short time periods. Figure [I] shows a modified Antarctic ice core record.
Figure [I] (Original Source SPPI.org no longer available)
The total temperature range is approximately 12°C (-9°C to +3°C). The variability is dramatic even though a 70–year smoothing average was applied. The diagram compares the peak temperatures in the current interglacial with those of the four previous interglacials. The horizontal scale on the x-axis is too small to identify even the length of the instrumental record.
Steve Goreham shows how small a portion it is in this diagram of the last 10,000 years (Figure [II]).
Another graph shows the same period, the Holocene Optimum, in a different form (Figure [III]).
(Read the whole thing.)
The null hypothesis about “climate change” is that recent warming, whatever its true extent, is of a piece with natural variations in Earth’s temperature. I have yet to read anything that refutes the null hypothesis. A lot of what has been written seems, at first glance, to do so. But it does not do so. It assumes, or aims to prove, a causal connection between the steady rise in atmospheric CO2 that has accompanied the industrialization and mechanization of the world and the coincidental — and halting — rise in the temperature record since Earth began to emerge from the Little Ice Age. Thus the inability of simplistic climate models, which are heavy on CO2 effects, to accurately “hindcast” actual temperature changes, that is, to replicate them from the vantage point of the present.
But most of the public “knows” only the scare story told by the red line in Figure 1. There’s no context. The explanation (“CO2 bad”) is superficial and misleading. But it sells the story that pseudo-scientists and politicians like James Hansen, Gavin Schmidt, Michael Mann, and Al Gore. want to sell. And which is sold with the eager assistance of the pro-big-government media outlets in the U.S. (i.e., most of them). It sells the story that leftists want to sell because it supports their need to control the lives of others through the agency of government.
A SCARE-TACTIC DEBUNKED: THE MYTHICAL, EVER-RISING, 30-YEAR AVERAGE
Our local weather Nazi, of whom I have written before, jumped on his high horse and lectured viewers about the 401 (?) consecutive months of above-average temperatures. He didn’t come out and say it — this time — but his thoughts and prayers are running in the direction of a climatic version of gun confiscation. Just take away those fossil fuels, etc., and Earth will return to its “correct” temperature. In his case, because anything above 75 in Austin is too warm for him, attaining the “correct” temperature would require a return to something like a real ice age.
In any event, the statistic that has the weather Nazi — and other climate hysterics — all a-twitter goes like this. The global temperature for every month since February 1985 has exceeded the rolling, 30-year average for that month. This statistic must be derived from surface thermometer readings, inasmuch as satellite readings didn’t begin until the late 1970s. We know all about those surface thermometer readings: spotty coverage, poor siting (often in locations surrounded by concrete and traffic), missing data, and — worst of all — frequent downward adjustments of historical numbers to make recent decades look hotter than they were. There’s no mention of the “pause” between the El Niños of the late 1990s and mid 2010s, of course.
Here’s something closer to the truth, based on satellite-recorded temperatures in the lower troposphere, from the Global Temperature Report by the Earth System Science Center of the University of Alabama-Huntsville:
Here are the yearly averages:
- The anomalies are small.
- There are many negative values before the onset of the major El Niño that began late in 2014 and lasted until mid-2016. (A negative value means that the reading for a month was below the 30-year average for that month.)
- The effects of that El Niño are wearing off.
Note to local weather Nazi: Give it a rest.
TAKING A STEP BACK — “GLOBAL” TEMPERATURES IN PERSPECTIVE
The “official” GISS set of temperature records (here) comprises surface thermometer records going back to January 1880. It takes a lot of massaging to construct a monthly time series of “global” temperatures that spans 137 years, with spotty coverage of Earth’s surface (even now), and wide variability in site conditions. There’s the further issue of data manipulation, the most recent example of which was the erasure of the pause that had lasted for almost 19 years.
Taking the GISS numbers at face value, for the moment, what do they suggest about changes in Earth’s temperature (whatever that means)? Almost nothing, when viewed in proper perspective. When viewed, that is, in terms of absolute (Kelvin) temperature readings:
Yes, there’s an upward trend of about 1 degree K (or 1 degree C) per century. And, yes, it’s statistically significant. But the statistical significance is due to the strong correlation between time and temperature. The trend doesn’t explain why Earth’s temperature is what it is. Nor does it explain why it has varied over the past 137 years.
Those variations have been minute. The maximum of 288.79K is only 1.1 percent higher than the minimum of 285.68K. This minuscule difference must be swamped by measurement and estimation errors. It is credible that Earth’s average temperature — had it been measured consistently over the past 137 years — would have changed less (or more) than the GISS record indicates. It is credible that the observed uptrend is an artifact of selective observation and interpretation. It has become warmer over the past 30 years where I live, for example, but the warming is explained entirely by the urban heat-island effect.
A proper explanation of the minute variations in Earth’s temperature — if real — would incorporate all of the factors that influence Earth’s temperature, starting from Earth’s core and going out into the far reaches of the universe (e.g., to account for the influence of cosmic radiation). Among many things, a proper explanation would encompass the effects of the expansion of the universe, the position and movement of the Milky Way, the position and movement of the Solar System, and the position and movement of Earth within the Solar System, and variations in Earth’s magnetic field.
But global climate models (or GCMs) focus entirely on temperature changes and are limited to superficial factors that are hypothesized to cause those changes — but only those factors that can be measured or estimated by complex and often-dubious methods (e.g., the effects of cloud cover). This is equivalent to searching for one’s car keys under a street lamp because that’s where the light is, even though the car keys were dropped 100 feet away.
The deeper and probably more relevant causes of Earth’s ambient temperature are to be found, I believe, in Earth’s core, magma, plate dynamics, ocean currents and composition, magnetic field, exposure to cosmic radiation, and dozens of other things that — to my knowledge — are ignored by GCMs. Moreover, the complexity of the interactions of such factors, and others that are usually included in GCMs, cannot possibly be modeled.
- Changes in Earth’s temperature are unknown with any degree of confidence.
- At best, the changes are minute.
- The causes of the changes are unknown.
- It is impossible to model Earth’s temperature or changes in it.
It is therefore impossible to say whether and to what extent human activity causes Earth’s temperature to change.
It is further impossible for a group of scientists, legislators, or opinionizers to say whether Earth’s warming — if indeed it is warming — is a bad thing. It is a good thing for agriculture — up to some point. It’s a good thing for human comfort (thus the flight of “snowbirds”) — up to some point. But for reasons given above, it’s truly unknown whether those points, and others, will be reached. But as they are, human beings will adapt, as they have in the past — unless their ability to adapt is preempted or hampered by costly regulations and counterproductive resource reallocations.
Science is not on the side of the doom-sayers, no matter how loudly they protest that it is.
Related reading (listed chronologically):
Stephen McIntyre and Ross McKitrick, “Corrections to the Mann et. al. (1998) Proxy Data Base and Northern Hemispheric Average Temperature Series“, Energy and Environment, Vol. 14, No. 6, 2003
Freeman Dyson, “Heretical Thoughts about Science and Society“, from Many Colored Glass: Reflections on the Place of Life in the Universe, University of Virgina Press, 2007
Anthony Watts, “Surface Temperature Uncertainty Quantified“, Watts Up With That?, January 20, 2011
Anthony Watts, “The Metrology of Thermometers“, Watts Up With That?, January 22, 2011
Ron Clutz, “Temperatures According to Climate Models“, Science Matters, March 24, 2015
Dr. Tim Ball, “Long-Term Climate Change: What Is a Reasonable Sample Size?“, Watts Up With That?, February 7, 2016
The Global Warming Policy Foundation, Climate Science: Assumptions, Policy Implications, and the Scientific Method, 2017
John Mauer, “Through the Looking Glass with NASA GISS“, Watts Up With That?, February 22, 2017
David R. Henderson and Charles L. Hooper, “Flawed Climate Models“, Hoover Institution, April 4, 2017
Mike Jonas, “Indirect Effects of the Sun on Earth’s Climate“, Watts Up With That?, June 10, 2017
George White, “A Consensus of Convenience“, Watts Up With That?, August 20, 2017
Jennifer Marohasy, “Most of the Recent Warming Could be Natural“, Jennifer Marohasy, August 21, 2017
Richard Taylor, “News from Vostok Ice Cores“, Watts Up With That?, October 8, 2017
Ian Flanigan, “Core of Climate Science Is in the Real-World Data“, Watts Up With That?, November 22, 2017
Eric Worrall, “Claim: Climate Driven Human Extinction ‘in the Coming Decades or Sooner’“, Watts Up With That?, November 23, 2017
Rupert Darwall, “A Veneer of Certainty Stoking Climate Alarm“, Competitive Enterprise Institute, November 28, 2017
Anthony Watts, “New Paper: The Missing Link between Cosmic Rays, Clouds, and Climate Change on Earth“, Watts Up With That?, December 19, 2017
David Archibald, “Baby It’s Cold Outside – Evidence of Solar Cycle Affecting Earth’s Cloud Cover“, Watts Up With That?, December 31, 2017
Anthony Watts, “‘Flaws in Applying Greenhouse Warming to Climate Variability’: A Post-Mortem Paper by Dr. Bill Gray“, Watts Up With That?, January 18, 2018
Dale Leuck, “Fake News and 2017 Near-Record Temperatures“, Watts Up With That?, January 21, 2017
Christopher Booker, Global Warming: A Case Study in Groupthink, The Global Warming Policy Foundation, February 2018
Will Happer, “Can Climate Models Predict Climate Change?“, PragerU, February 5, 2018
Anthony Watts, “A Never-Before Western-Published Paleoclimate Study from China Suggests Warmer Temperatures in the Past“, Watts Up With That?, February 11, 2018
H. Sterling Burnett, “Alarmist Climate Researchers Abandon Scientific Method“, The American Spectator, February 27, 2018
Anthony Watts, “Alarmists Throw In the Towel on Poor Quality Surface Temperature Data – Pitch for a New Global Climate Reference Network“, Watts Up With That?, March 2, 2018
David Archibald, “The Modern Warm Period Delimited“, Watts Up With That?, March 10, 2018 (This piece offers further evidence — not put forward as “proof” — of the influence of solar flux on cosmic radiation, which affects cloud formation and thus climate. The time scale analyzed is far longer than the 25-year period in which the coincidence of rising CO2 emissions and temperatures led many climate scientists — and many more non-scientists — to become
“global warming” “climate change” “climate catastrophe” hysterics.)
Anthony Watts, “New Paper Tries to Disentangle Global Warming from Natural Ocean Variations“, Watts Up With That?, March 15, 2018
Anthony Watts, “Climate Scientist Admits Embarrassment over Future Climate Uncertainty“, Watts Up With That?, March 16, 2018
Renee Hannon, “Modern Warming – Climate Variability or Climate Change?“, Watts Up With That?, March 28, 2018
David Archibald, “It Was the Sun All Along — So Say the Bulgarians“, Watts Up With That?, April 9, 2018
Mark Fife, “Reconstructing a Temperature History Using Complete and Partial Data“, Watts Up With That?, April 19, 2018
Jamal Munshi, “The Charney Sensitivity of Homicides to Atmospheric CO2: A Parody“, Watts Up With That?, April 20, 2018
Peter L. Ward, “Ozone Depletion, Not Greenhouse Gases Cause for Global Warming, Says Researcher“, R&D Magazine, April 20, 2018 (It makes as much sense, if not more sense, than global climate models, which only predict the past.)
Nic Lewis, “Impact of Recent Forcing and Ocean Heat Uptake Data on Estimates of Climate Sensitivity“, Climate Etc., April 24, 2018
Christopher Monckton of Brenchley, “Did Official Climatology Know Its Predictions Were Nonsense?“, Watts Up With That?, April 24, 2018
Dr. Willie Soon, Dr. Ronan Connolly, and Dr. Michael Connolly, “New Paper Shows Issues with Temperature Records: Comparing the Current and Early 20th Century Warm Periods in China“, Watts Up With That?, June 13, 2018
Wim Röst, “How Earth Became a Hothouse: By H2O“, Watts Up With That?, June 15, 2018
Dr. Tim Ball, “Anthropogenic Global Warming (AGW) a Premeditated Crime Against Science Justified with Artificial Certainty“, Watts Up With That?, June 18, 2018
Willis Eschenbach, “Dr. Hansen’s Statistics“, Watts Up With That?, June 30, 2018
Clyde Spencer, “Analysis of James Hansen’s 1988 Prediction of Global Temperatures for the Past 30 Years“, Watts Up With That?, June 30, 2018
Ross McKitrick and John Christy, “The Hansen Forecasts 30 Years Later“, Climate Etc., July 3, 2018
Viv Forbes, “Watching Weather Waves, Missing Climate Tides“, American Thinker, July 10, 2018
Dr. Tim Ball, “The Heartbeat of the Deep State: Climate, Corruption, and Lack of Accountability“, Watts Up With That?, July 28, 2018
Christopher Monckton of Brenchley, “Climatology’s Startling Error — An Update“, Watts Up With That?, July 30, 2018
Francis Menton, “How Do You Tell If the Earth’s Climate System ‘Is Warming’?”, Manhattan Contrarian, August 9, 2018
Kenneth Richard, “AGW Gatekeepers Censor The CO2-Climate Debate By Refusing To Publish Author’s Response To Criticism“, NoTricksZone, August 27, 2018
Javier, “What Is Warming the Earth?“, Watts Up With That?, August 28, 2018
Andy May, “The Great Climate Change Debate: William Happer v. David Karoly“, Watts Up With That?, September 1-3, 2018
Dr. Tim Ball, “Empirical Evidence Shows Temperature Increases Before CO2 Increase in ALL Records”, Watts Up With That?, September 9, 2018
John Hinderaker, “Climate Alarmism Fails the Test of Observation“, Power Line, September 17, 2018
AGW: The Death Knell (with many links to related reading and earlier posts)
Not-So-Random Thoughts (XIV) (second item)
AGW in Austin?
Understanding Probability: Pascal’s Wager and Catastrophic Global Warming
The Precautionary Principle and Pascal’s Wager
AGW in Austin? (II) (with more links to related reading)
Hot Is Better Than Cold: A Small Case Study