Global warming is in retreat at the moment, even as CO2 concentration increases. If one looks at the data, increased CO2 concentration does not cause, and has not caused, a large world-wide increase in temperature. The greenhouse effect, however real, is neither large enough nor independent of other effects to cause substantial warming.

In the last article in this series, we showed the measured increase in CO2 concentration and a physically realistic projection of future changes. Here we will look at current temperature data with respect to the CO2 data, and then review the literature that caused such alarm.

Temperature can be measured in many ways, but, for the purpose of looking at the greenhouse effect, the best measurements are of the lower troposphere. The troposphere itself is the lowest portion of Earth’s atmosphere, and is approximately 17 km thick.[1] Satellite measurements of the lower troposphere, about 2.5 km thick, would be the most sensitive to the greenhouse effect, because that is where the heat would be trapped.

A plot of the Northern Hemisphere temperature in the lower troposphere over a recent period[2] shows the temperature holding constant or decreasing, even while the CO2 concentration at the Mauna Loa site[3] (MLO) was increasing. (Mind you, the Mauna Loa site is near the top of this region. Local temperature measurements at Mauna Loa reflect the satellite measurements.)

Several characteristics of this plot deserve mention. First, the large temperature value in 1998 is not spurious, but is the result of a large El Niño effect[4], which quickly dissipated. Other than that effect, the overall temperature appears to hold constant or decrease slightly except for seasonal swings; the CO2 concentration continues to rise.

Close examination of the data shows that the temperature rose early in each year. While this was coincident with seasonally increasing CO2 early on, it dropped off while the CO2 was still rising. Note that increased temperature not only releases CO2 from the oceans but evaporates water vapor as well. And water vapor forms clouds, which reflect sunlight and cause cooling.

The important point to take from this data is not that the greenhouse effect cannot contribute to global temperature, but that it is not the dominant effect.[5]

Because this conclusion is at odds with the 2007 report by the Intergovernmental Panel on Climate Change (IPCC)[6], a look at their referenced data is in order. (Note that the IPCC report summarizes the data from other sources, occasionally very suspect sources.[7])

The main source of global warming visualization comes from a plot of the global temperature for the last 1000 years by Mann, Bradley, and Hughes.[8]

This is really two plots, a blue plot of temperatures estimated mostly from tree rings and a red plot of surface temperatures from various monitors. This plot was dubbed the “hockey stick”, and has been dissected for errors by a plethora of scientists.[9] The details of the controversy are mostly beyond the scope of a popular discussion, so we will concentrate on just two artifacts of the plot.

First, note that the growth at the end of the temperature measurements (red curve) is that same large El Niño effect shown before, although the report fails to mention that. Instead the report represents this change as man-made, without any supporting data. (Models aren’t data.)

Second, look at the blue plot of historical temperatures. These temperatures are taken largely from tree ring proxies. These become temperatures by measuring the growth rings of old trees and relating these to temperature through a process called reconstruction.

Of particular note is the period around the 1960s. Below is a plot of the tree ring data[10] against the surface measurements of temperature[11]. The base period for both curves reflects the 1961-1990 period as specified in the tree ring data.

Two things stand out instantly. First the errors in the tree ring data are large; go back and check out the gray bars in the previous graph. In science, the blue curve is actually far less meaningful than the envelope of possible error.

Second, and most importantly, the trend of the tree ring proxies for temperature is going down while the trend of the measured surface temperature does not. The tree ring data does not faithfully represent known measurements. (This discrepancy was obviously unwanted by this particular group of climate scientists; this tree ring data was dropped from the archived data set[12].)

This, and other data, calls into question the use of tree rings for historical temperature reconstruction. These reconstructions assume that trees responded linearly with temperature. But tree growth can be limited by parameters other than temperature such as water, and, at higher elevations, CO2 concentration. The growth can also be accelerated by these same things; the observed increase in CO2 can fertilize tree growth.[13] This observed growth acceleration indicates that the limiting factor is not temperature, so that tree ring data may not be measuring temperature.

So if tree ring estimates of historical temperature are suspect, what can we use? The other available proxies include ice core data and sea floor sediment from all over the globe. A plot of these various data sets by Loehle[14], normalized to a common baseline, shows a wholly different picture from the tree ring data.

Here, the shaded areas are the dates for the Medieval Warm Period and the Little Ice Age. These periods are well known historically. For instance, Greenland was first settled by the Norse in the 900s, but died out due to increasing cold and ice by the 1400s. Europe, during this time, had long season farming both further north and at higher elevations. Curiously, during the Little Ice Age, Europe recorded increased storms and reduced farming seasons with famine.

A look back at the tree ring data shows that it largely glossed over the Little Ice Age and missed the end of the Medieval Warm Period if the errors bars are ignored. The IPCC commented that the Medieval Warm Period was endemic to the North Atlantic and was not global, but it is hard to have climate be local then and global now. From radioisotope data[15], contaminants are delivered from the Northern Hemisphere to the Southern Hemisphere in about two years. Volcanic contaminates are delivered around the globe, that is, within the same hemisphere, in less time[16].

But the current temperature data and the non-tree ring data makes certain conclusions obvious.

The global temperature of the earth has seen an increase in the last century and a half. However, the increase is not exceptional when compared to historical trends. And CO2 is not the cause, man-made or not.

A note of caution is in order. CO2 concentrations are directly measured; global temperatures are not. All temperature data, while having a relatively local source, has been filtered, censored, averaged, extrapolated, and otherwise massaged to produce the curves given above. In order to be believable, the scientists in question must exhibit a high level of integrity and release accurate data and algorithms on a timely basis during peer review. The scientists who wrote, or contributed to, the IPCC report and provided the temperature curves failed in this regard. Apparently, they have even destroyed original data rather than turn it over to Freedom of Information requests. The IPCC report has been suborned by their work and their lack of scientific integrity.

In summary, global warming is not dominated by burning fossil fuels. As such, political global warming is a hoax. The proponents of global warming claim a consensus, but it is only among themselves. And they have, according to their own emails, made every attempt to control the peer-reviewed literature. This forced unanimity of view, in which contrary opinions are suppressed, can only be termed political zeal. It is certainly not scientific.

Because the current data will not support the global warming fraud, the comment that CO2 is actually causing climate change, not global warming, is now in vogue. There is no scientific basis for such a statement, but that’s for another discussion. Or, perhaps, global cooling should be the next topic, perhaps possible causes of warming, perhaps the source of the CO2.

[1] Wikipedia, Troposphere
[2] Data from NASA Satellite collected and corrected by John Christy, University of Alabama, Huntsville, Atmospheric Science Department
[3] C. D. Keeling, S. C. Piper, R. B. Bacastow, M. Wahlen, T. P. Whorf, M. Heimann, and H. A. Meijer, Exchanges of atmospheric CO2 and 13CO2 with the terrestrial biosphere and oceans from 1978 to 2000. I. Global aspects, SIO Reference Series, No. 01-06, Scripps Institution of Oceanography, San Diego, 88 pages, 2001.
[4] Trenberth, K. E.; et al. (2002). “Evolution of El Niño – Southern Oscillation and global atmospheric surface temperatures”. Journal of Geophysical Research 107 (D8): 4065
[5] Douglass, D.H., J.R. Christy, 2009: Limits on CO2 climate forcing from recent temperature data of Earth. Energy & Environment, 20, 178-189
[6] IPCC, Climate Change 2007: Synthesis Report
[7] For a short summary, Is it time to overhaul the IPCC?, Christian Science Monitor, 2/10/2010
[8] Mann, Michael E.; Bradley, Raymond S.; Hughes, Malcolm K. (1998), “Global-scale temperature patterns and climate forcing over the past six centuries”, Nature 392: 779–787
[9] Wikipedia, Hockey Stick Controversy
[10] K. R. Briffa et al., Nature 391, 678 (1998)
[11] P. Brohan, J.J. Kennedy, I. Harris, S.F.B. Tett and P.D. Jones, Uncertainty estimates in regional and global observed temperature changes: A new data set from 1850, J. G. R., Vol. 111, D12106, 24 June 2006 (HADCRUT3 data set)
[12] Data archived by the National Oceanic and Atmospheric Organization, US Dept. of Commerce, ftp://ftp.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/n_hem_temp/briffa2001jgr3.txt (no guarantees here, they can change the data at will.)
[13] Graybill, D.A. and Idso, S.B., Detecting the Aerial Fertilization Effect of the Atmospheric CO2 Enrichment in Tree Ring Chronologies, Global Biogeochemical Cycles, 7 (1993), 81-95 (There are a lot of regerences on this subject, most very technical.)
[14] Loehle, Craig, Energy & Environment, 18 No. 7+8, 2007
[15] Wikipedia, Carbon-14, check out the delay of the C14 isotope from the atmospheric nuclear tests in going from the Northern Hemisphere (Austria measurement) to the Southern Hemisphere (New Zealand measurement)
[16] Start at NASA Facts On-Line, Volcanoes and Global Cooling and NASA, Earth Science Reference Handbook

Today, every news show seems to talk about carbon dioxide (CO2), but usually with very little reference to actual data. Much of the news is dominated by political scare tactics or abject rejection of all science. So, here we describe, in a series of articles, the actual data as available on-line with references and some added science discussion.

However, before we get started, let’s separate science from conjecture and politics. Scientists rarely use the word believe. Those that do are usually theorists, including modelers, and use the word believe because they don’t have the data to back up their statements. Second, scientists never use the word consensus, ever. There are also several substitute words that fall into this category, like incontrovertible and high agreement. Those that use these words are not real scientists, or have left science for another calling. In general, follow the data, and keep an open mind.

And there is a reasonable amount of data. To start, take a look at the air around us, with water vapor excluded for the moment. Most of the air is nitrogen, followed by oxygen and an inert gas, argon. Carbon dioxide, CO2, is just 0.035% or 350 parts per million by volume (ppmv) on average. Water vapor, H2O, is not shown here because it varies so widely over the whole earth.[1]

Indeed, water vapor can vary from near zero to over 3%, depending on the temperature. Of course that is because water has both liquid and solid phases (ice) as well. The temperature determines the dominance of each phase. By the time the temperature reaches -60 degrees C near the poles, water vapor is negligible. Over the surface of the earth, however, water vapor averages about 1% or 1000 ppmv, 3 times CO2.

Although water vapor dominates any science of radiation heating (or cooling), the main trace molecules, carbon dioxide and methane, dominate discussions. Carbon dioxide, in particular, has been studied for some time now and is increasing as a minor constituent in the atmosphere. Methane depends on where you look. Because its main sources are on the surface, its concentration falls off rapidly with height.

The most complete data set for carbon dioxide comes from the Mauna Loa site, located at over 11,000 feet near a volcano in Hawaii.[2] These measurements of the CO2 concentration in air have been made continuously since 1958. They show a continuous increase with a yearly cycle.

Of course, the growth of CO2 concentration did not start in 1958; it has been going on for some time. For instance, using ice core data, the concentration has been growing since 1744. Ice core data are the measurements of air constituents in tapped bubbles in layered ice, generally from Antarctica. Recent data in the last three centuries are from the Siplo station.[3]

So the increase in CO2 concentration has been going on for centuries. In fact, using ice core data from the end of the last ice age, about 13,000 years ago, the concentration of CO2 has been increasing gradually for some time. The concern is the rapid increase in the last half of a century. (Note the suppressed zero which exaggerates the increase.)

All this data begs the question: what will happen in the future? Hofmann, from the NOAA Earth System Research Laboratory in Boulder, Colorado, has fit the Mauna Loa data to an exponential curve and, thus, projects that the total CO2 will double by the year 2050 to 580 ppmv. He also notes that the concentration growth tracks the population growth, which, if continued would indicate a maximum CO2 level of 430 ppmv, using the population projections of the United Nations.[4]

While this seems enormous, it is in line with the projections of the Intergovernmental Panel on Climate Change[5] (IPCC) whose report shows the CO2 concentration, for various scenarios, reaching 475 – 525 ppmv in 2050, and then keep going. And this report is being used to drive governmental change in energy production.

Of course, when projections such as these are used with such dire consequences, one must always ask whether they are properly done. All models must meet at least two criteria: fit all the data not just some and be physically reasonable. And the exponential fit is erroneous for those two very obvious reasons.

First, if the Siplo ice core data is added to the Mauna Loa data, the exponential doesn’t fit any longer. The projections of the fit to the earlier data are poor. Second, the exponential fit is not bounded for future projection, but goes to infinity, a very unphysical situation.

So, what happens if we include the physical processes into the problem, and demand that the fitted curve that we use for projections is bounded and be validated by the earlier data? In that case, we can get an estimate of the upper limit, along with a time frame for its occurrence.[6]

The method is straightforward; the type of mathematical curve is called a growth curve. It is frequently used to describe complex situations in which the growth is the sum of many complex processes. In this case the curve saturates at about 400 ppmv in 2028. (Error bars have been placed about the ice core data.)

Can such a curve be used for projections? Somewhat, but with caution. However, this projection is far better than the projections given by Hofmann and IPCC; at least the actual processes over time are described and the upper limits brought into play.

Now, what does this mean to the climate? None of this data or analysis ties CO2 concentration to world-wide temperature growth. None of the data even indicates the source of the CO2. This merely indicates the potential for the CO2 change in the near term. Thus, conclusions about the meaning of this data must be deferred to another discussion with more pertinent data.

1. The data here is from NASA Earth Fact Sheet modified to reflect the year 1987

2. C. D. Keeling, S. C. Piper, R. B. Bacastow, M. Wahlen, T. P. Whorf, M. Heimann, and H. A. Meijer, Exchanges of atmospheric CO2 and 13CO2 with the terrestrial biosphere and oceans from 1978 to 2000. I. Global aspects, SIO Reference Series, No. 01-06, Scripps Institution of Oceanography, San Diego, 88 pages, 2001.

3. Neftel, A., E. Moor, H. Oeschger, and B. Stauffer. 1985. Evidence from polar ice cores for the increase in atmospheric CO2 in the past two centuries. Nature 315:45-47.

4. World Population Prospects, 2007. The 2006 Revision, Highlights, Working Paper No. ESA/P/WP.202, United Nations, Department of Economic and Social Affairs, Population Division, New York.

5. IPCC, Climate Change 2007: Synthesis Report

6. For the mathematically curious, the analytical expression used is the Loglogisic distribution with a reversed axis. The parameter estimates were done using Maximum Likelihood Estimation, and converged quickly using Gauss-Newton. The curve has a negative skewness demanded by the data; curves with positive skewness did not fit because of the Siplo data.

Professionally, I am, first, a trained physicist, (atomic and molecular physics), second, a working statistician specializing in stochastic models, and, lately due to illness, the editor of a local on-line newspaper. And, being naturally curious, I have followed the scientific debate over global warming.

• I understand the measured increase in background CO2 concentration, and the concerns there from.
• I understand the decrease in the carbon isotope ratio, and the possible causes.
• I understand the correlation of measured temperatures with CO2 concentration, albeit with no correlation in the last decade. (Mind, correlation is not cause and effect.)
• I understand the importance of good models, or lack thereof, for cloud formation. Reflection of sunlight by clouds aids cooling, and water vapor is the predominant greenhouse gas by far.
• I understand the measurement of emissivity of the earth over time, and the contradiction that poses for many climate models.
• I understand the erroneous statistical model used by climate scientists to evaluate historical temperatures over the last few millennium.
• I understand the dearth of chaotic and stochastic processes in climate models that produces a false robustness. (insufficient computing power)

I understand, and I am still learning, as any scientist would. But I cannot explain my knowledge to lay people; I lack that skill. Even my neighbors laughed at me when I tried, so little did they understand of what I said. So I have remained silent.

But I cannot remain silent when important climate scientists are found to be dishonest in their work. And this is what happened with the release of over 1000 emails from Climate Research Unit at the University of East Anglia in Great Britain. In those emails, the scientists admitted to falsifying temperature data and jury-rigging their models. They admitted choosing to hide, or possibly, destroy original data rather than release such data to the public. (Why hide data unless it condemns your work?) They blackballed their critics, forcing them out of peer reviewed journals, even to the point of having journal editors removed who would not cooperate. One scientist even celebrated the death of a critic.

What makes this important is straightforward; these are the very scientists who wrote a good part of the United Nation’s latest report by the Intergovernmental Panel on Climate Change (IPCC). That report is the reason for the EPA’s regulation of CO2 emissions, the basis for the cap and trade legislation before Congress, and the driving force behind the proposed Copenhagen treaty. Any one of those governmental changes will drive the cost of energy, and transportation, up astronomically. And Kent is a town whose economy depends on transportation.

Of course, my voice is small and inconsequential in the face of such a political juggernaut. But the total lack of personal and scientific integrity in these men requires whatever amplification I can give it.