This article originally appeared in Forbes online on March 19, 2013.
Although “climate” is generally associated with periods of at least three decades, less than one and one-half decades following mid-1970s “scientific” predictions that the next Ice Age was rapidly approaching, the media trumpeted a new and opposite alarm…a man-made global warming crisis. Previously, even the prestigious National Academy of Sciences had issued a warning that there was “a finite possibility that a serious worldwide cooling could befall the earth within the next 100 years.”
Hot climate frenzy was fueled by a convergence of geopolitical circumstances. Theoretical model calculations at that time, including some at NOAA’s Geophysical Fluid Dynamic Laboratory, began to indicate that substantial global warming could result from increasing CO2 levels. Then, during a particularly hot 1988 summer in many U.S. regions, NASA’s James Hansen testified before Senator Al Gore’s steamy 1988 Committee on Science, Technology and Space, that he was 99% certain that temperatures had in fact, increased due to greenhouse warming. Also, the Cold War had just ended, and the Union of Concerned Scientists redirected its attention from nuclear disarmament to a new “global warming threat”. They issued a widely publicized statement in the New York Times condemning human carbon emissions as the villain.
This was also a time when Third World countries, by force of numbers, and European socialist Green parties, through powers of aggressiveness, seized control of the United Nations to advance globalization goals, which emerging global warming alarm perfectly served. Accordingly, the United Nations established the Framework Convention on Climate Change (UNFCCC) to organize conferences, along with the UN’s Intergovernmental Panel on Climate Change (IPCC), which, prior to any studies, concluded that climate change caused by fossil burning posed a global threat.
Within about half of a legitimate climate period after the earlier global cooling scares, the UNFCCC had already determined that “climate change” was, by their definition: “a change of climate, which is attributed directly or indirectly to human activity, that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods.” Key words here are “attributed” to “human activities” which alter the “atmosphere”…greenhouse gases (CO2 specifically).
Accordingly, when you hear references to “climate change” in the media these days, you can be pretty certain that it’s going to discuss some observed or inevitable catastrophe attributed to “bad” greenhouse warming caused by burning evil fossil fuels. We almost never see commentary reminding us that CO2 and warm conditions are both really great for agriculture and most Earth critters.
Yes, Climate Change is Real!
Indeed, climate really does change without any help from us, and we can be very grateful that it does. Over the past 800,000 years, much of the Northern Hemisphere has been covered by ice up to miles thick at regular intervals lasting about 100,000 years each. Much shorter interglacial cycles like our current one lasting 10,000 to 15,000 years have offered reprieves from bitter cold.
And yes, from this perspective, current temperatures are abnormally warm. By about 12,000 to 15,000 years ago Earth had warmed enough to halt the advance of glaciers and cause sea levels to rise, and the average temperature has held fairly constant ever since, with brief intermissions.
Although temperatures have been generally mild over the past 500 years, we should remember that significant fluctuations are still normal. The past century has witnessed two distinct periods of warming. The first occurred between 1900 and 1945, and the second, following a slight cool-down, began quite abruptly in 1975. That second period rose at quite a constant rate until 1998, and then stopped and began falling again after reaching a high of 1.16ºF above the average global mean.
But What About Those “Observed” Human Greenhouse Influences?
The IPCC stated in its last 2007 Summary for Policymaker’s Report that “Most of the observed increase in globally averaged temperature since the mid-20th century [which is very small] is very likely due to the observed increase in anthropogenic [human-caused] greenhouse gas concentrations.” And there can be no doubt here that they are referring to CO2, not water vapor, which constitutes the most important greenhouse gas of all. That’s because the climate models don’t know how to “observe” it, plus there aren’t any good historic records to enable trends to be revealed.
Besides, unlike carbon, there is little incentive to attach much attention to anthropogenic water vapor. After all, no one has yet figured out a way to regulate or tax it.
A key problem in determining changes and influences of water vapor concentrations in the Earth’s atmosphere is that they are extremely variable. Differences range by orders of magnitude in various places. Instead, alarmists sweep the problem to one side by simply calling it a CO2 “feedback” amplification effect, always assuming that the dominant feedback is “positive” (warming) rather than “negative” (cooling). In reality, due to clouds and other factors, those feedbacks could go both ways, and no one knows for sure which direction dominates climate over the long run.
Treating water vapor as a known feedback revolves around an assumption that relative humidity is a constant, which it isn’t. Since it is known to vary nearly as widely as actual water vapor concentrations, no observational evidence exists to support a CO2 warming amplification conclusion.
But let’s imagine that CO2 is the big greenhouse culprit rather than a bit-player, and that its influences are predominately warming. Even if CO2 levels were to double, it would make little difference. While the first CO2 molecules matter a lot, successive ones have less and less effect. That’s because the carbon that exists in the atmosphere now has already “soaked up” its favorite wavelengths of light, and is close to a saturation point. Those carbon molecules that follow manage to grab a bit more light from wavelengths close to favorite bands, but can’t do much more…there simply aren’t many left-over photons at the right wavelengths. For those of you who are mathematically inclined, that diminishing absorption rate follows a logarithmic curve.
Who Hid the Carbon Prosecuting Evidence?
Since water vapor and clouds are so complex and difficult to model, their influences are neglected in IPCC reports. What about other evidence to support an IPCC claim that “most” mid-century warming can “very likely” be attributed to human greenhouse emissions? Well, if it’s there, it must me very well hidden, since direct measurements seem not to know where it is.
For example, virtually all climate models have predicted that if greenhouse gases caused warming, there is supposed to be a telltale “hot spot” in the atmosphere about 10 km above the tropics. Weather balloons (radiosondes) and satellites have scanned these regions for years, and there is no such pattern. It wasn’t even there during the recent warming spell between 1979 (when satellites were first available) and 1999.
How have the committed greenhouse zealots explained this? They claim that it’s there, but simply hidden by “fog in the data”…lost in the statistical “noise”. Yet although radiosondes and satellites each have special limitations, their measurements show very good agreement that the “human signature” doesn’t exist. Suggestions to the contrary are based upon climate model data outputs which yield a wide range of divergence and uncertainty…an example of garbage in, gospel out.
Why Did the Last Ice Age End and the Good Times Begin?
A recent study conducted by researchers at Grenoble University in France and published in Science magazine suggests that atmospheric carbon dioxide levels produced from natural factors contributed to the sharp warming that ended the last Ice Age about 15,000 years ago. Scientists have long recognized that Ice Ages and brief interglacial interludes (like our current one) are caused by variations in the Earth’s orbit around the sun. It is also well known that when oceans warm (in this instance due to intensification of sunlight energy), huge amounts of absorbed CO2 are released, exactly like the off-gassing of a carbonated drink when warmed. The bottom line is that past atmospheric CO2 is wholly controlled by the Earth’s temperature and climate, not the other way around.
The Grenoble study authors did not factor in influences the warming oceans would have had upon evaporated of water vapor, that primary atmospheric greenhouse gas. Rather, it focused upon analyzing air bubbles trapped in Antarctic ice cores to determine the trace CO2 concentrations at different times over thousands of years, concluding that the last Ice Age ended within 200 years or less after CO2 levels rose…and possibly that there was no time lag at all. This finding challenges previous research indicating that CO2 levels rose some 600-800 years or so after temperatures increased.
There is another possibility warranting consideration as well, one involving slight differences in Arctic and Antarctic deglaciation time cycles. Since atmospheric CO2 is a global condition, and the solar “Milankovich” mechanism of deglaciation begins with warming in the high North, it is plausible to imagine that Arctic warming would have preceded and subsequently influenced Antarctic deglaciation through the release of both water vapor and CO2. This, in turn, might help to explain different temperature lag conclusions.
Still, if true, might this “lock-step” relationship between CO2 and temperature increases be interpreted to suggest that a CO2 greenhouse effect may have accelerated (amplified) the warming? That’s not smoking gun evidence, but it is certainly possible, and even quite probable. So if this truly is the case, then by how much? Determining that is the big rub, because the findings can be interpreted in different ways.
Consider, for example, that atmospheric CO2 concentrations at the end of the last Ice Age, when rapid deglaciation occurred were less than half of today’s levels. At the same time, the influence of that lower concentration would also have been much greater than today due to the logarithmic absorption pattern. Therefore, the CO2 amplification factor might have contributed proportionately much more influence than today, causing it to be less relevant to current circumstances.
Accurate dating of samples is very difficult and subject to large unknowns. And while carbon dioxide levels have been constantly increasing, most of all estimated warming since 1900 occurred before the mid-1940s. Despite those continuously rising CO2 levels, global mean temperatures have been flat over at least the past decade.
Regarding That Confidence That We Are Changing the Climate
While even IPCC admits that correlation between different occurrences, however convincing, doesn’t prove cause and effect, this uncertainty principle is often given little priority in summary conclusions they convey to the public. In their first 1990 report, IPCC played on this confusion, claiming: “The size of this warming is broadly consistent with the predictions of climate models, but is also of the same magnitude as natural climate variability.” They could have just as easily said that the greenhouse theory didn’t explain climate, but natural variability did.
Later, the IPCC artfully changed the term “correlation” to “attribution”, meaning that even if observations couldn’t be objective correlated, they could be subjectively attributed if those who wrote the “consensus” conclusions wished to do so. That consensus is what anonymous, politically-determined representatives who approve the entire reports decide fits their preferred narrative.
The final draft of IPCC’s second report for example, contained a passage which was removed which said: “None of these studies cited has shown clear evidence that we can attribute the observed changes [in global temperature] to the specific cause of increases in greenhouse gases.” Yet, the final, printed 1996 report claimed: “…there is evidence of an emerging pattern of climate response to forcings by greenhouse gases and sulphate aerosols…from geographical, seasonal and vertical patterns of temperature change…These results point towards human influence on climate.” The IPCC Summary concludes that “the balance of evidence” suggests a discernible human influence on climate.
Remarkably, another 1996 publication “The Holocene”, written by some of the same Summary authors said: “Estimates of…natural variability are critical to the problem of detecting an anthropogenic [human] signal…We have estimated the spectrum…from paleo-temperature proxies and compared it with…general [climate] circulation models…none of the three estimates of the natural variability spectrum agree with each other…Until…resolved, it will be hard to say, with confidence, that an anthropogenic climate signal has or has not been detected.”
The True Nature of Climate Change…It Ain’t a New Thing
Keep in mind that cyclical, abrupt and dramatic global and regional temperature fluctuations have occurred since long before humans invented agriculture, industries, internal combustion engines and carbon-trading schemes. Yet atmospheric CO2 levels have remained relatively low over the past 650,000 years, even during the six previous interglacial periods when global temperatures were as much as 9ºF warmer than temperatures we currently enjoy.
Many natural factors are known to contribute to these changes, although even the most sophisticated climate models and theories they are based on cannot predict the timing, scale (either up or down), or future impacts- much less the marginal influences we humans might contribute. So let’s be very thankful for the good times that global warming affords as long as we are fortunate to have it. The real climate crisis will arrive when our planet’s warm Ice Age vacation ends.