Global Cooling

May 8, 2009

But knowing that it is Global Warming. Belief or facts. Create confusion with apparent facts. Overnight experts claming to know what nobody else on this planet knows, or that is being hidden – the conspiracy feeling. There are bloggers insisting on the existence of global cooling (Ref 1). To prove this, a multitude of isolated facts are produced, going from periodic solar activity, the oceanic temperature to graphs showing seasonal variations of arctic ice. A luster of scientific seriosity impresses many readers not aware of the pitfalls.

The worldwide consensus regarding climatic change is this (Wikipedia)  : In February 2007, the IPCC released a summary of the forthcoming Fourth Assessment Report. According to this summary, the Fourth Assessment Report finds that human actions are “very likely” the cause of global warming, meaning a 90% or greater probability. Global warming in this case is indicated by an increase of 0.75 degrees in average global temperatures over the last 100 years.
The phenomenon of arctic shrinkage has been observed since at least 1950 and it is accelerating, with the cold winter of 2007 marking an exception (Ref 2)
At least since the publication of the IPCC in 2007, global warming is a fact accepted by scientists and informed laymen (Ref 3).

I am a layman, but I know that the worldwide ecology is infinetely complex. Climate change, desertification, the polar melting, the migration of flora and fauna due to these factors, all this is being researched seriously and requires profound knowledge. Research has been conducted for decades and the conclusions are concordant. Computer programs extrapolating climatic changes can simply not be reproduced or invalidated by anybody during a commercial break, on his laptop.

The ongoing debate over the very existence of global warming has no scientific base, it is an ideologic one. Let’s recall the Bush administration. They systematically denied any human influence on the climate change, they boycotted the Kyoto agreement, systematically blocking all efforts of the worldwide community to take effective measures against the CO2-induced climatic change. One specifity of the US debate is a tendency to engage and perseverate in undefensable theories like : infallibility of a totally deregulated economy, creationism, worldwide menace through terrorism, feeling of superiority over all international laws and organisations etc.
The Bush administration preached low taxes, a lean state and the inexistence of any climatic problems for the simple reason that they did not want to spend any money for infrastructure, for international organisations, and among these was the Kyoto protocol – money was the motif. Behind a religious, almost ideologic façade, this administration simply and effectively directed all public and private financial resources towards their own lobbies and for specific objectives : finance sector, oil industry, military-industrial complex etc. The general public bought this smokescreen so well, because the average GOP voter was convinced that every tax $ was wasted. A certain avarice led people to vote not for their convictions, but for these reasons. In this way, the GOP administration has ransacked their countries resources and partly those of the worldwide economy and ecology.

After this small recapitulation lets get on with the climate debate. Based on pseudo-scientific facts presenting a fragmented and thus distorted view, the overwhelming positive evidence is simply eclipsed. Psychologically certain people might get a kick from convincing a group of adepts to believe a theory that is diametrically opposed to the conclusions of thousands of scientists. I would call this the conspiracy feeling : a group is formed by a hermetic belief that is contrary to the mainstream.  Negationism is a well-known subterfuge used in many contexts. Apart from the all-time classic (the shoa), it is very popular to displace the discussion, psychologically this is known als freudian repression. Creationsts build a complex system only to contradict the evident existence of natural evolution. The pope makes backwards contortions to avoid admitting that jews can go to heaven without being first converted to christianism, he creates arguments to deny priests a right of marriage, to deny the necessity of using condoms, just to cling to the holy scripture in the face of overwhelming evidence. In the US, politics has castrated scientific research for years only to please certain religious groups fighting against abortion etc. While forbidding stemcell research, use of embryos and red genetic technology, green genetic engineering was supported without any criticism, again using a tactic of denial, namely of it’s potential dangers. Denial is also used by adepts of sects believing in intelligent design, in the return of aliens … the list is endless.

I see this psychological trait of denial or negationism as quite characteristic of certain sections of the US population. It is quite remarkable to see such a degree of irrational thinking in a socienty claiming to be so rational and scientifically savvy. Of course, admitting that greenhouse-gases are the main culprit for global warming might be a confession too painful to make, since the US are the largest producer of CO2 worldwide. It could challenge the way of life of a nation.

Ref 1 : Wikipedia : Global cooling was a conjecture during the 1970s of imminent cooling of the Earth’s surface and atmosphere along with a posited commencement of glaciation. This hypothesis never had significant scientific support, but gained temporary popular attention due to a combination of press reports that did not accurately reflect the scientific understanding of ice age cycles, and a slight downward trend of temperatures from the 1940s to the early 1970s. Today, General scientific opinion is that the Earth has not durably cooled, but undergone global warming throughout the 20th century.[“Summary for Policymakers” (PDF). Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Intergovernmental Panel on Climate Change. 2007-02-05. Retrieved on 2007-02-02.]

Ref 2 Wikipedia : Records of Arctic Sea ice from the United Kingdom’s Hadley Centre for Climate Prediction and Research go back to the turn of the 20th century, although the quality of the data before 1950 is debatable. Still, these records show a persistent decline in Arctic Sea ice over the last 50 years.[2].
Reliable measurements of sea ice edge begin within the satellite era. From the late 1970s, the Scanning Multichannel Microwave Radiometer (SMMR) on Seasat (1978) and Nimbus 7 (1978–87) satellites provided information that was independent of solar illumination or meteorological conditions. The frequency and accuracy of passive microwave measurements improved with the launch of the DMSP F8 Special Sensor Microwave/Imager SSMI in 1987. Both the sea ice area and extent are estimated, with the latter being larger, as it is defined as the area of ocean with at least 15% sea ice.
In a modelling study of the 52-year period from 1948 to 1999 Rothrock and Zhang (2005) find a statistically significant trend in Arctic ice volume of −3% per decade; splitting this into wind-forced and temperature forced components shows it to be essentially all caused by the temperature forcing.
The trends from 1979 to 2002 have been a statistically significant Arctic decrease and an Antarctic increase that is probably not significant, depending exactly on which time period is used. The Arctic trends of −2.5% ± 0.9% per decade; or about 3% per decade[3]. Climate models simulated this trend in 2002[4], and attributed it to anthropogenic forcing.
The September ice extent trend for 1979–2004 is declining by 7.7% per decade[5].
Record Low Arctic Sea Ice in 2007 – Showing the Northwest passage open
In 2007 the ice melt accelerated. The minimum extent fell by more than a million square kilometers, the biggest decline ever. The minimum extent fell to 4.14 million km², by far the lowest ever. New research shows the Arctic Sea ice to be melting faster than predicted by any of the 18 computer models used by the Intergovernmental Panel on Climate Change in preparing its 2007 assessments.[6]
While the Northern Hemisphere sea ice reached new record lows, on September 12, 2007 the Southern Hemisphere sea ice area reached 15.91 million km², close to the maximum recorded of 16.02 million km².[7]
The Antarctic increase is 0.8% per decade[8] although this depends on the period being considered. Vinnikov et al.[9] find the NH reduction to be statistically significant but the SH trend is not.
Scientific parameter to quantify the extent of sea ice
In the overall mass balance, the volume of sea ice depends on the thickness of the ice as well as the areal extent. While the satellite era has enabled better measurement of trends in areal extent, accurate ice thickness measurements remain a challenge. “Nonetheless, the extreme loss of this summer’s sea ice cover and the slow onset of freeze-up portends lower than normal ice extent throughout autumn and winter, and the ice that grows back is likely to be fairly thin”[2].

Ref 3 : Global warming is the increase in the average temperature of the Earth’s near-surface air and oceans since the mid-twentieth century and its projected continuation. Global surface temperature increased 0.74 ± 0.18 °C (1.33 ± 0.32 °F) during the last century.[1]A[›] The Intergovernmental Panel on Climate Change (IPCC) concludes that anthropogenic greenhouse gases are responsible for most of the observed temperature increase since the middle of the twentieth century,[1] and that natural phenomena such as solar variation and volcanoes probably had a small warming effect from pre-industrial times to 1950 and a small cooling effect afterward.[2][3] These basic conclusions have been endorsed by more than 40 scientific societies and academies of science,B[›] including all of the national academies of science of the major industrialized countries.[4]
Climate model projections summarized in the latest IPCC report indicate that global surface temperature will probably rise a further 1.1 to 6.4 °C (2.0 to 11.5 °F) during the twenty-first century.[1] The uncertainty in this estimate arises from the use of models with differing climate sensitivity, and the use of differing estimates of future greenhouse gas emissions. Some other uncertainties include how warming and related changes will vary from region to region around the globe. Most studies focus on the period up to 2100. However, warming is expected to continue beyond 2100 even if emissions stop, because of the large heat capacity of the oceans and the long lifetime of carbon dioxide in the atmosphere.[5][6]
Increasing global temperature will cause sea levels to rise and will change the amount and pattern of precipitation, probably including expansion of subtropical deserts.[7] The continuing retreat of glaciers, permafrost and sea ice is expected, with the Arctic region being particularly affected. Other likely effects include shrinkage of the Amazon rainforest and Boreal forests, increases in the intensity of extreme weather events, species extinctions and changes in agricultural yields.
Political and public debate continues regarding the appropriate response to global warming. The available options are mitigation to reduce further emissions; adaptation to reduce the damage caused by warming; and, more speculatively, geoengineering to reverse global warming. Most national governments have signed and ratified the Kyoto Protocol aimed at reducing greenhouse gas emissions.


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