Climate science: observations vs. models
Richard K. Moore
This document continues to evolve, based on continuing research. The latest version is always maintained at this URL:
You can click on any graphic in this document to see a larger image.
Global temperatures in perspective
Let’s look at the historical temperature record, beginning with the long-term view. For long-term temperatures, ice-cores provide the most reliable data. Let’s look first at the very long-term record, using ice cores from Vostok, in the Antarctic. Temperatures are shown relative to 1900, which is shown as zero.
Here we see a very regular pattern of long-term temperature cycles. Most of the time the Earth is in an ice age, and about every 125,000 years there is a brief period of warm tempertures, called an interglacial period. Our current interglacial period has lasted a bit longer than most, indicating that the next ice age is somewhat overdue.
These long-term cycles are probably related to changes in the eccentricity of the Earth’s orbit, which follows a cycle of about 100,000 years. We also see other cycles of more closely-spaced peaks, and these are probably related to other cycles in the Earth’s orbit. There is an obliquity cycle of about 41,000 years, and a precession cycle, of about 20,000 years, and all of these cycles interfere with one another in complex ways. Here’s a tutorial from NASA that discusses the Earth’s orbital variations:
Next let’s zoom-in on the current interglacial period, as seen in Vostok and Greenland, again using ice-core data.
Here we see that the Antarctic emerged from the last ice age about 1,000 years earlier than the Arctic. While the Antarctic has oscillated up and down throughout the interglacial period, the Arctic has been on a steady decline towards the next ice age for the past 3,000 years.
As of 1900, in comparison to the whole interglacial period, the temperature was 2°C below the maximum in Vostok, and 3°C below the maximum in Greenland. Thus, as of 1900, temperatures were rather cool for the period in both hemispheres, and in Greenland temperatures were close to a minimum.
During this recent interglacial period, temperatures in both Vostok and Greenland have oscillated through a range of about 4°C, although the patterns of oscillation are quite different in each case. In order to see just how different the patterns are, let’s look at Greenland and Vostok together for the interglacial period. Vostok is shown with a dashed line.
The patterns are very different indeed. While Greenland has been almost always above the 1900 base line, Vostok has been almost always below. And in the period 1500-1900, while Greenland temperatures were relatively stable, within a range of 0.5°C, Vostok went through a radical oscillation of 3°C, from an extreme high to an extreme low.
These dramatic differences between the two arctic regions might be related to the Earth’s orbital variations (See NASA tutorial). On the other hand, we may be seeing a regulatory mechanism, based on the fact that the Southern Hemisphere is dominated by oceans, while most of the land mass is in the Northern Hemisphere. Perhaps incoming heat, though retained by the northern continents, leads to evaporation from the oceans and increased snowfall in the Antarctic. Whatever the reasons, the differences between the two arctic regions are striking.
Let’s now look at the average of Greenland and Vostok temperatures over the interglacial period:
8,500 BC — 1900
Here we see that the average temperature has followed a more stable pattern, with more constrained oscillations, than either of the hemispheres. The graph shows a relatively smooth arc, rising from the last ice age, and descending steadily over the past 4,000 years toward the next ice age. Here’s the average again, together with Vostok and Greenland:
8,500 BC — 1900
Notice how the average is nearly always nestled between the Arctic and Antarctic temperatures, with the Arctic above and the Anatarctic below. It does seem that the Antarctic is acting as a regulatory mechanism, keeping the average temperature always moderate, even when the Arctic is experiencing high temperatures. I don’t offer this as a theory, but simply as an observation of a possibility.
We can see that the average temperature tells us very little about what is happening in either arctic region. We cannot tell from the average that Arctic temperatures were 3°C higher in 1500 BC, and that glacier melting might have been a danger then. And the average does not tell us that the Antarctic has almost always been cool, with very little danger of ice-cap melting at any time. In general, the average is a very poor indicator of conditions in either arctic region.
If we want to understand warming-related issues, such as tundra-melting and glacier-melting, we must consider the two polar regions separately. If glaciers melt, they do so either because of high Arctic temperatures, or high Antarctic temperatures. Whether or not glaciers are likely to melt cannot be determined by global averages.
Next let’s take a closer look at Vostok and Greenland since 500 BC:
500 BC — 1900
Again we see how the Antarctic temperatures balance the Arctic, showing almost a mirror image over much of this period. From 1500 to 1800, while the Arctic was experiencing the Little Ice Age, it seems almost as if the Antarctic was getting frantic, going into radical oscillations in an effort to keep the average up near the base line.
Beginning about 1800 we have an unusual situation, where both arctic regions begin warming rapidly at the same time, as each follows its own distinct pattern. This of course means that the average will also be rising. Keep in mind that everything we’ve been looking at so far has been before human-caused CO2emissions were at all significant.
Thus, just as human-caused emissions began to increase, around 1900, average temperatures were already rising sharply, from natural causes. There has been a strong correlation between rising average temperature and CO2 levels since 1900, arising from a coincidental alignment of three distinct trends. Whether or not rising CO2 levels have accelerated the natural increase in average temperature remains to be seen.
We’ll return to this question of CO2 causation, but first let’s look at some other records from the Northern Hemisphere, to find out how typical the Greenland record is of its hemisphere. This first record is from Spain, based on the mercury content in a peat bog, as published in Science, 1999, vol. 284. Note that this graph is backwards, with present day on the left.
Present day — 2,000 BC
This next record is from the Central Alps, based on stalagmite isotopes, as published in Earth and Planteary Science Letters, 2005, vol. 235.
0 AD — Present Day
And for comparison, here’s the Greenland record for the most recent 4,000 years:
2,000 BC — 1900
While the three records are clearly different, they do share certain important characteristics. In each case we see a staggered rise, followed by a staggered decline — a long-term up-and-down cycle over the period. In each case we see that during the past few thousand years, temperatures have been 3°C higher than 1900 temperatures. And in each case we see a steady descent towards the overdue next ice age. The Antarctic, on the other hand, shares none of these characteristics.
In the Northern Hemisphere, based on the shared characteristics we have observed, temperatures would need to rise at least 3°C above 1900 levels before we would need to worry about things like the extinction of polar bears, the melting of the Greenland ice sheet, or runaway methane release. We know this because none of these things have happened in the past 4,000 years, and temperatures have been 3°C higher during that period.
However such a 3°C rise seems very unlikely to happen, given that all three of our Nothern Hemisphere samples show a gradual but definite decline toward the overdue next ice age. Let’s now zoom-in on the temperature record since 1900, and see what kind of rise has actually occurred. Let’s turn to Jim Hansen’s latest article, published on realclimate.org, 2009 temperatures by Jim Hansen. The article includes the following two graphs.
Jim Hansen is of course one of the primary spokespersons for the human-caused-CO2-dangerous-warming theory, and there is some reason to believe these graphs show an exaggerated picture as regards to warming. Here is one article relevant to that point, and it is typical of other reports I’ve seen:
Son of Climategate! Scientist says feds manipulated data
Nonetheless, let’s accept these graphs as a valid representation of recent average temperature changes, so as to be as fair as possible to the warming alarmists. We’ll be using the red line, which is from GISS, and which does not use the various extrapolations that are included in the green line. We’ll return to this topic later, but for now suffice it to say that these extrapolations make little sense from a scientific perspective.
The red line shows a temperature rise of .7°C from 1900 to the 1998 maximum, a leveling off beginning in 2001, and then a brief but sharp decline starting in 2005. Let’s enter that data into our charting program, using values for each 5-year period that represent the center of the oscillations for that period. Here’s what we get for 1900-2008:
1900 — 2008
In order to estimate how these average changes would be reflected in each of the polar regions, let’s look at Greenland and Vostok together, from 1000 AD to 1900.
1000 — 1900
Vostok shown with dashed line
Here we can see that in 1900 the Antarctic was warming much faster the Arctic. As usual, the Antarctic was exhibiting the more extreme oscillations. In the most recent warming shown, from 1850 to 1900, the Arctic increased by only 0.5°C while the Antarctic increased by 0.75°C. As regards the average of these two inreases, the Antarctic contributed 60%, while the Arctic contributed 40%. If we assume these trends continue, and changes in global average are reflected in the polar regions, then we get the following estimate for temperature changes in the two polar regions:
1900 — 2008
(based on apportioning GISS changes,
60% to Vostok, 40% to Greenland)
Vostok shown with dashed line
This is only approximate, of course, but it is probably closer to the truth than apportioning the changes equally to the two polar regions. Let’s now look again at Greenland and Vostok together, for the past 4,000 years, with these apportioned GISS changes appended.
2,000 BC — 2008
Extended by GISS data
Vostok shown with feint line
We see here that both polar regions have remained below their maximum for this period. The Arctic has been nearly 2.5°C warmer, and the Antarctic about 0.5°C warmer. Perhaps CO2 is accelerating Antarctic warming, or perhaps Antarctica is simply continuing its erratic oscillations. In the Arctic however, temperatures are definitely following their long-term pattern, with no apparent influence from increased CO2 levels.
The recent warming period has given us a new peak in the Greenland record, one in a series of declining peaks. If you hold a ruler up to the screen, you’ll see that the four peaks shown, occuring about every 1,000 years, fall in a straight line. If the natural pattern continues, then the recent warming has reached its maximum in the Northern Hemisphere, and we will soon experience about two centuries of rapid cooling, as we continue our descent to the overdue next ice age. The downturn shown in the GISS data beginning in 2005 fits perfectly with this pattern.
Next let’s look at the Greenland-Vostok average temperature for the past 4,000 years, extended by the GISS data.
2,000 BC — 2008
Extended by GISS data
Here we see a polar-region subset of the famous hockey stick, on the right end of the graph — and we can see how misleading that is as regards the likelihood of dangerous warming. From the average polar temperature, we get the illusion that temperatures are warmer now at the poles than they’ve been any time since year 0. But as our previous graph shows, the Arctic has been about 1.5°C warmer during that period, and the Antarctic has been about 0.5°C warmer. And even the average has been nearly 0.5°C warmer, if we look back to 2,000 BC. So in fact we have not been experiencing alarmingly high temperatures recently in either hemisphere.
Dr. Hansen tells us the recent downturn, starting in 2005, is very temporary, and that temperatures will soon start rising again. Perhaps he is right. However, as we shall see, his arguments for this prediction are seriously flawed. What we know for sure is that a downward trend has begun. How far that trend will continue is not yet known.
So everything depends on the next few years. If temperatures turn sharply upwards again, then the IPCC may be right, and human-caused CO2 emissions may have taken control of climate. However, if temperatures continue downward, then climate has been following natural patterns all along in the Northern Hemisphere. The record-setting cold spells and snows in many parts of the Northern Hemisphere this winter seem to be a fairly clear signal that the trend is continuing downwards.
If so, then there has been no evidence of any noticeable influence on northern climate from human-caused CO2, and we are now facing an era of rapid cooling. Within two centuries we could expect temperatures in the Northern Hemisphere to be considerably lower than they were in the recent Little Ice Age.
We don’t know for sure which way temperatures will go, rapidly up or rapidly down. But I can make this statement:
As of this moment, based on the long-term temperature patterns in the Northern Hemisphere, there is no evidence that human-caused CO2 has had any effect on climate. The rise since 1800, as well as the downward dip starting in 2005, are entirely in line with the natural long-term pattern. If temperatures turn sharply upwards in the next few years, that will be the first-ever evidence for human-caused warming in the Northern Hemisphere.
The illusion of dangerous warming arises from a failure to recognize that global averages are a very poor indicator of actual conditions in either hemisphere.
If the downward trend continues in the Northern Hemisphere, as the long-term pattern suggests, we are likely to experience about two centuries of rapid cooling in the Northern Hemisphere, as we continue our descent toward the overdue next ice age.
As regards the the recent downturn, here are two other records, both of which show an even more dramatic downturn than the one shown in the GISS data:
Dr. John Christy
UAH Monthly Means of Lower Troposphere LT5-2
2004 – 2008
RSS MSU Monthly Anomaly – 70S to 82.5N (essentially Global)
2004 – 2008
Why haven’t unsually high levels of CO2significantly affected temperatures in the Northern Hemisphere?
One place to look for answers to this question is in the long-term patterns that we see in the temperature record of the past few thousand years, such as the peaks separated by about 1,000 years in the Greenland data, and other more closely-spaced patterns that are also visible. Some forces are causing those patterns, and whatever those forces are, they have nothing to do with human-caused CO2 emissions.
Perhaps the forces have to do with cycles in solar radiation and solar magnetism, or cosmic radiation, or something we haven’t yet identified. Until we understand what those forces are, how they intefere with one another, and how they effect climate, we can’t build useful climate models, except on very short time scales.
We can also look for answers in the regulatory mechanisms that exist within the Earth’s own climate system. If an increment of warming happens on the surface, for example, then there is more evaporation from the oceans, which cools the ocean and leads to increased precipitation. While an increment of warming may melt glaciers, it may also cause increased snowfall in the arctic regions. To what extent do these balance one another? Do such mechanisms explain why Antarctic temperatures seem to always be balancing the Arctic, as we have seen in the data?
It is important to keep in mind that CO2 concentrations in the atmosphere are tiny compared to water-vapor concentrations. A small reduction in cloud formation can more than compensate for a large increase in CO2 concentration, as regards the total greenhouse effect. If there is a precipitation response to CO2-warming, that could be very significant, and we would need to understand it quantitatively, by observing it — not by making assumptions and putting them in our models.
Vegetation also acts as a regulatory system. Plants and trees gobble up CO2; that is where their substance comes from. Greater CO2 concentration leads to faster growth, taking more CO2 out of the atmosphere. Until we understand quantitively how these various regulatory systems function and interact, we can’t even build useful models on a short time scale.
In fact a lot of research is going on, investigating both lines of inquiry — extraterrestrial forces as well as terrestrial regulation mechanisms. However, in the current public-opinion and media climate, any research not related to CO2 causation is dismissed as the activity of contrarians, deniers, and oil-company hacks. Just as the Bishop refused to look through Galileo’s telescope, so today we have a whole society that refuses to look at many of the climate studies that are available.
From observation of the patterns in climate history, the evidence indicates that regulatory mechanisms of some kind are operating. It’s not so much the lack of a CO2-effect that provides evidence, but rather the constrained, oscillatory pattern in the average polar temperatures over the whole interglacial period. Whenever you see contrained oscillations in a system, that is evidence of a regulatory mechanism — some kind of thermostat at work.
Direct evidence for climate-regulation mechanisms
I’d like to draw attention to one example of a scientist who has been looking at one aspect of the Earth’s regulatory system. Roy Spencer has been conducting research using the satellite systems that are in place for climate studies. Here are his relevant qualifications:
Roy W. Spencer is a principal research scientist for the University of Alabama in Huntsville and the U.S. Science Team Leader for the Advanced Microwave Scanning Radiometer (AMSR-E) on NASA’s Aqua satellite. He has served as senior scientist for climate studies at NASA’s Marshall Space Flight Center in Huntsville, Alabama.
He describes his research in a presentation available on YouTube:
In the talk he gives a lot of details, which are quite interesting, but one does need to concentrate and listen carefully to keep up with the pace and depth of the presentation. He certainly sounds like someone who knows what he’s talking about. Permit me to summarize the main points of his research:
When greenhouse gases cause surface warming, a response occurs, a ‘feedback response’, in the form of changes in cloud and precipitation patterns. The CRU-related climate models all assume the feedback response is a positive one: any increment of greenhouse warming will be amplified by knock-on effects in the weather system. This assumption then leads to the predictions of ‘runaway global warming’.
Spencer set out to see what the feedback response actually is, by observing what happens in the cloud-precipitation system when surface warming is occurring. What he found, by targeting satellite sensors appropriately, is that the feedback response is negative rather than positive. In particular, he found that the formation of storm-related cirrus clouds is inhibited when surface temperatures are high. Cirrus clouds are themselves a powerful greenhouse gas, and this reduction in cirrus cloud formation compensates for the increase in the CO2 greenhouse effect.
This is the kind of research we need to look at if we want to build useful climate models. Certainly Spencer’s results need to be confirmed by other researchers before we accept them as fact, but to simply dismiss his work out of hand is very bad for the progress of climate science. Consider what the popular website SourceWatch says about Spencer.
We don’t find there any reference to rebuttals to his research, but we are told that Spencer is a “global warming skeptic” who writes columns for a free-market website funded by Exxon. They also mention that he spoke at conference organized by the Heartland Institute, that promotes lots of reactionary, free-market principles. They are trying to discredit Spencer’s work on irrelevant grounds, what the Greeks referred to as an ad hominem argument. Sort of like, “If he beats his wife, his science must be faulty”.
And it’s true about ‘beating his wife’ — Spencer does seem to have a pro-industry philosophy that shows little concern for sustainability. That might even be part of his motivation for undertaking his recent research, hoping to give ammunition to pro-industry lobbyists. But that doesn’t prove his research is flawed or that his conclusions are invalid. His work should be challenged scientifically, by carrying out independent studies of the feedback process. If the challenges are restricted to irrelevant attacks, that becomes almost an admission that his results, which are threatening to the climate establishment, cannot be refuted. He does not hide his data, or his code, or his sentiments. The same cannot be said for the warming-alarmist camp.
What are we to make of Jim Hansen’s prediction that rapid warming will soon resume?
Once again, I refer you to Dr. Hansen’s recent article, 2009 temperatures by Jim Hansen. Jim explains his prediction methodlolgy in this paragraph, emphasis added:
The global record warm year, in the period of near-global instrumental measurements (since the late 1800s), was 2005. Sometimes it is asserted that 1998 was the warmest year. The origin of this confusion is discussed below. There is a high degree of interannual (year‐to‐ year) and decadal variability in both global and hemispheric temperatures.Underlying this variability, however, is a long‐term warming trend that has become strong and persistent over the past three decades. The long‐term trends are more apparent when temperature is averaged over several years. The 60‐month (5‐year) and 132 month (11‐year) running mean temperatures are shown in Figure 2 for the globe and the hemispheres. The 5‐year mean is sufficient to reduce the effect of the El Niño — La Niña cycles of tropical climate. The 11‐ year mean minimizes the effect of solar variability — the brightness of the sun varies by a measurable amount over the sunspot cycle, which is typically of 10‐12 year duration.
As I’ve emphasized above, Jim is assuming there is a strong and persistent warming trend, which he of course attributes to human-caused CO2 emissions. And then that assumption becomes the justification for the 5 and 11-year running averages. Those running averages then give us phantom ‘temperatures’ that don’t match actual observations. In particular, if a downard decline is beginning, the running averages will tend to ‘hide the decline’, as we see in these alarmist graphs from the article with their exaggerated ‘hockey stick’.
It seems we are looking at a classic case of scientists becoming over-attached to their model. In the beginning there was a theory of human-caused global warming, arising from the accidental convergence of three independent trends, combined with the knowledge that CO2 is a greenhouse gas. That theory has now become an assumption among its proponents, and actual observations are being dismissed as “confusion” because they don’t agree with the model. One is reminded again of the Bishop who refused to look through Galileo’s telescope, so as not to be confused about the ‘fact’ that the Earth is the center of the universe.
The climate models have definitely strayed into the land of imaginary epicycles. The assumption of CO2 causation, plus the preoccupation with an abstract global average, creates a warming illusion that has no connection with reality in either hemisphere. This mathematical abstraction, the global average, is characteristic of nowhere. It creates the illusion of a warming crisis, when in fact no evidence for such a crisis exists. In the context of IPCC warnings about glacers melting, runaway warming, etc., the global-average hockey stick serves as deceptive and effective propaganda, but not as science.
As with the Ptolemaic model, there is a much simpler explantation for our recent era of warming, at least in the Northern Hemisphere: long-term temperature patterns are continuing, from natural causes, and natural regulatory mechanisms have compensated for the greenhouse effect of human-caused CO2 emissions. There is no strong reason to believe that CO2 has been affecting the Southern Hemisphere either, given the natural record of rapid and extreme oscillations — which often go opposite to northern trends.
This simpler explanation is based on actual observations, and requires no abstract mathematical epicycles or averages — but it removes CO2 from the center of the climate debate. And just as politically powerful factions in Galileo’s day wanted the Earth to remain the center of the universe, powerful factions today want CO2 to remain at the center of climate debate, and global warming to be seen as a threat.
What is the real agenda of the politically powerful factions who are promoting global-warming alarmism?
One thing we always need to keep in mind is that the people at the top of the power pyramid in our society have access to the very best scientific information. They control dozens, probably hundreds, of high-level think tanks, able to hire the best minds, and carrying out all kinds of research we don’t hear about. They have access to all the secret military and CIA research, and a great deal of influence over what research is carried out in think tanks, the military, and in universities.
Just because they might be promoting faulty science for its propaganda value, that doesn’t mean they believe it themselves. They undoubtedly know that global cooling is the most likely climate prognosis, and the actions they are promoting are completely in line with such an understanding.
Cap-and-trade, for example, won’t reduce carbon emissions. Rather it is a mechanism that allows emissions to continue, while pretending they are declining — by means of a phony market model. You know what a phony market model looks like. It looks like Reagan and Thatcher telling us that lower taxes will lead to higher government revenues due to increased business activity. It looks like globalization, telling us that opening up free markets will “raise all boats” and make us all prosperous. It looks like Wall Street, telling us that mortgage derivatives are a good deal, and we should buy them. And it looks like Wall Street telling us the bailouts will restore the economy, and that the recession is over. In short, it’s a con. It’s a fake theory about what the consequences of a policy will be, when the real consequences are known from the beginning.
Cap-and-trade has nothing to do with climate. It is part of a scheme to micromanage the allocation of global resources, and to maximize profits from the use of those resources. Think about it. Our ‘powerful factions’ decide who gets the initial free cap-and-trade credits. They run the exchange market itself, and can manipulate the market, create derivative products, sell futures, etc. They can cause deflation or inflation of carbon credits, just as they can cause deflation or inflation of currencies. They decide which corporations get advance insider tips, so they can maximize their emissions while minimizing their offset costs. They decide who gets loans to buy offsets, and at what interest rate. They decide what fraction of petroleum will go to the global North and the global South. They have ‘their man’ in the regulation agencies that certify the validity of offset projects, such as replacing rainforests with tree plantations, thus decreasing carbon sequestration. And they make money every which way as they carry out this micromanagement.
In the face of global cooling, this profiteering and micromanagenent of energy resources becomes particularly significant. Just when more energy is needed to heat our homes, we’ll find that the price has gone way up. Oil companies are actually strong supporters of the global-warming bandwagon, which is very ironic, given that they are funding some of the useful contrary research that is going on. Perhaps the oil barrons are counting on the fact that we are suspicious of them, and asssume we will discount the research they are funding, as most people are in fact doing. And the recent onset of global cooling explains all the urgency to implement the carbon-management regime: they need to get it in place before everyone realizes that warming alarmism is a scam.
And then there’s the carbon taxes. Just as with income taxes, you and I will pay our full share for our daily commute and for heating our homes, while the big corporate CO2 emitters will have all kinds of loopholes, and offshore havens, set up for them. Just as Federal Reserve theory hasn’t left us with a prosperous Main Street, despite its promises, so theories of carbon trading and taxation won’t give us a happy transition to a sustainable world.
Instead of building the energy-efficient transport systems we need, for example, they’ll sell us biofuels and electric cars, while most of society’s overall energy will continue to come from fossil fuels, and the economy continues to deteriorate. The North will continue to operate unsustainably, and the South will pay the price in the form of mass die-offs, which are already ticking along at the rate of six million children a year from malnutrition and disease.
While collapse, suffering, and die-offs of ‘marginal’ populations will be unpleasant for us, it will give our ‘powerful factions’ a blank canvas on which to construct their new world order, whatever that might be. And we’ll be desperate to go along with any scheme that looks like it might put food back on our tables and warm up our houses.