The notion of a static, unchanging climate is foreign
Aug 2nd, 2008 by Rick Arms
The notion of a static, unchanging climate is foreign to the history of the earth or any other planet with a fluid envelope. The fact that the developed world went into hysterics over changes in global mean temperature of a few tenths of a degree will astound future generations.
Such hysteria simply represents the scientific illiteracy of much of the public, the susceptibility of the public to the Goebbelian substitution of repetition for truth, and the exploitation of these weaknesses by politicians, environmental promoters, and, after 20 years of media drum beating, many others as well.
Climate is always changing. We have had ice ages and warmer periods when alligators were found in Spitzbergen. Ice ages have occurred in a hundred thousand year cycle for the last 700 thousand years, and previous warm periods appear to have been warmer than the present despite CO2 levels being lower than they are now. More recently, we have had the medieval warm period and the little ice age. During the latter, alpine glaciers advanced to the chagrin of overrun villages.
Since the beginning of the 19th Century these glaciers have been retreating. Frankly, we don’t fully understand either the advance or the retreat. For small changes in climate associated with tenths of a degree, there is no need for any external cause. The earth is never exactly in equilibrium. The motions of the massive oceans where heat is moved between deep layers and the surface provides variability on time scales from years to centuries. Recent work (Tsonis et al, 2007), suggests that this variability is enough to account for all climate change since the 19th Century. Supporting the notion that man has not been the cause of this unexceptional change in temperature is the fact that there is a distinct signature to greenhouse warming: surface warming should be accompanied by warming in the tropics around an altitude of about 9km that is about 2.5 times greater than at the surface.
Measurements show that warming at these levels is only about 3/4 of what is seen at the surface, implying that only about a third of the surface warming is associated with the greenhouse effect, and, quite possibly, not all of even this really small warming is due to man. This further implies that all models predicting significant warming are greatly overestimating warming. This should not be surprising. According to the UN’s Intergovernmental Panel on Climate Change, the greenhouse forcing from man made greenhouse gases is already about 86 % of what one expects from a doubling of CO2 (with about half coming from methane, nitrous oxide, freons and ozone), and alarming predictions depend on models for which the sensitivity to a doubling for CO2 is greater than 2C which implies that we should already have seen much more warming than we have seen thus far, even if all the warming we have seen so far were due to man.
This contradiction is rendered more acute by the fact that there has been no significant global warming for the last ten years. Modelers defend this situation by arguing that aerosols have cancelled much of the warming, and that models adequately account for natural unforced internal variability. However, a recent paper (Ramanathan, 2007) points out that aerosols can warm as well as cool, while scientists at the UKs Hadley Centre for Climate Research recently noted that their model did not appropriately deal with natural internal variability thus demolishing the basis for the IPCC iconic attribution. Interestingly (though not unexpectedly), the British paper did not stress this. Rather, they speculated that natural internal variability might step aside in 2009, allowing warming to resume. Resume? Thus, the fact that warming has ceased for the past decade is acknowledged.
Given that the evidence (and I have noted only a few of many pieces of evidence) strongly suggests that anthropogenic warming has been greatly exaggerated, the basis for alarm due to such warming is similarly diminished.
However, the really important point is that the case for alarm would still be weak even if anthropogenic global warming were significant. Polar bears, arctic summer sea ice, regional droughts and floods, coral bleaching, hurricanes, alpine glaciers, malaria, etc. etc. all depend not on some global average of surface temperature, but on a huge number of regional variables including temperature, humidity, cloud cover, precipitation, and direction and magnitude of wind.
The state of the ocean is also often crucial. Our ability to forecast any of these over periods beyond a few days is minimal. Yet, each catastrophic forecast depends on each of these being in a specific range. The odds of any specific catastrophe actually occurring is almost zero. This was equally true for earlier forecasts: famine for the 1980’s, global cooling in the 1970’s, Y2K and many others. Regionally, year to year fluctuations in temperature are over four times larger than fluctuations in the global mean. Much of this variation has to be independent of the global mean; otherwise the global mean would vary much more.
This is simply to note that factors other than global warming are more important to any specific situation. This is not to say that disasters will not occur; they always have occurred and this will not change in the future. Fighting global warming with symbolic gestures will certainly not change this. However, history tells us that greater wealth and development can profoundly increase our resilience.
Given the above, one may reasonably ask why there is the current alarm, and, in particular, why the astounding upsurge in alarmism of the past 2 years. When an issue like global warming is around for over twenty years, numerous agendas are developed to exploit the issue.
