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CONSIDERATIONS ON CLIMATE & GLOBAL WARMING |
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There is growing concern about the danger of global warming caused by Man (widely believed to be an established fact) and the subsequent consequences thereof, including coastal flooding and the engulfment of various populated islands.1 Added to this is the danger of large amounts of fresh water from the Greenland sheets and caps changing the ratio of salt to water in the Atlantic.2 This would cause major changes in the climate of Europe, increasing mountain glacier growth, as happened at the end of the last ice age and temporarily delaying the onset of further warming.3
The advocates of global warming point to the following factors as evidence of cause: (1) mankind has been producing ever greater quantities of carbon dioxide, methane, and other greenhouse gases; (2) in a laboratory setting, carbon dioxide and other greenhouse gases have been shown to hold heat in the atmosphere; (3) warmer air allows higher levels of water vapor (tiny water droplets) to remain in the atmosphere (tiny water droplets) - and water vapor is the greatest of the greenhouse gases, so the increase in water vapor should result in even warmer temperatures and, due to the warmer atmospheric temperatures, hold even more water vapor, causing a spiraling cycle. Further, the much greater amount of water vapor would result in increased cloud cover which might eventually cover the whole globe, causing almost no irradition of heat into space to cool the planet! This data has been backed up by world-wide research showing that temperatures in various cities world-wide are warmer than at any time since we have had the ability to take such measurements. The evidence for the effects are the following: warmer temperatures will likely result in the melting of the ice sheets and caps of Greenland and Antarctica; this has been shown by diatom fossils taken from Antarctica which have been dated to 3 million years ago - when the temperatures were as high as some models show they will rise sometime in the early to middle part of the 21st Century - indicating that the continent had largely been flooded, with plant-life flourishing on the islands there; further, at least one study has shown that ocean temperatures have increased by a degree (and oceans, which make up over 70% of the Earth's surface, are a major determinant of climate!). Added to this, sea-levels over the last 100 years have shown a steady increase of 2 cm each year! Now comes new evidence that the ice shelves are melting and that the bottom of the ice sheets of West Antarctica (by far the most massive) are warm-based, so that a layer of water separates them from the continental crust. This means that as the ice shelves break away from the continent they may pull the ice sheets from the continent and into warmer waters where they can melt. This would certainly cause a major increase in sea levels.
The first issue that must be raised is whether there have, in fact, been major, abnormal changes in world climate. The evidence for this, unfortunately, greatly conflicts. Research taken in various cities worldwide seems to indicate that, overall, global climate has changed. Dr. Hansen of the [NASA] Goddard Space Institute for Space Studies has explicitly stated that the research gathered by himself and others has accounted for the so-called heat-island effect caused by decreased ground-cover and increased albedo rates. Others, such as Dr. Sherwood Idso of the USDA Agricultural Research Service, finding that an exhaustive study of small town weather-stations in the United States over 70 years provided evidence that the overall US climate actually decreased, has stated that until all land-based data has been collected and filtered for the heat island effect, we will not know whether or not the planet has actually warmed.4 Further, such research has not typically included the temperature of the ocean (over 70% of the earth's surface)or the earth's atmosphere. Logs of water temperatures taken by various ships over time has not shown changes in ocean temperature and of the two major tests of ocean temperatures taken by the US and the UK, the tests were contradictory - one showing an increase and one a decrease of about 1 degree Farenheit! Dr. John Christy of the University of Alabama and Dr. Roy Spencer of the [NASA] Marshall Space Flight Center, using 15 years of satellite research collected from the National Oceanic and Atmospheric Administration (NOAA) have not found any evidence of a warming trend in the data. While Hansen has pointed out that this only shows temperatures since 1979 and could be skewed by water vapor interfering with the microwave radiation reception, he admitted that there should be some evidence in the data showing a warming trend and assumed that the team needs to re-read the data. Christy has pointed out that the satellite research covers the entire planet evenly not in a somewhat spotty fashion (as, by necessity, Hansen's temperature readings were taken) and not in industrial areas (or heat islands!).5 Thus, it would appear that the evidence that global warming is occurring is uncertain. The second issue regarding global warming is whether the evidence shows mankind is responsible. Dr. Broecker has admitted that about half of the supposed increase in temperatures recorded in Hansen's research occurred prior to 1940 - whereas almost all so-called "greenhouse gas" emissions occurred after that time! |
Further, the record indicates that natural temperature changes have occurred quite often in the past, including the so-called Medieval Optimum temperature warmth period and the "mini-Ice Age" which appears to have been the major cause for the extermination of the Nordic Greenland colony in the 1400s. As far as the evidence that the oceans have been rising by 2 cm a year for 100 years, the problem is that the buoys used for these measurements have only been around for 100 years! Further, the evidence shows that sea levels have been rising, on the whole, since the end of the Pleistocene. And, there appears to be a correlation between solar activity and changing weather patterns on earth, since even a 1 degree change in solar magnitude can drastically affect the weather and can be cumulative. So, again, even if we assume that global warming is occurring, the evidence does not appear to indicate that Man is responsible. Finally, let us assume that climate change is occurring and mankind is responsible. Does this mean that global warming will cause the Antarctic ice sheets and caps to melt, deluging the world's coasts and submerging various island-nations as asserted by Dr. Stephen Schneider in defense of his computer models? If the supposed increase in temperatures occurs, then temperatures later this century will approximate those existing about 3 million years ago, the period at which Dr. Harwood [University of Nebraska] has carbon-dated the diatom fossils found in Antarctica.6 However, Dr. Sugden of the University of Edinburgh, using argon isotopes in volcanic ash covering the region in which Harwood's diatoms were found has dated the surrounding ice to 8 million years ago! Thus, it is far from certain that Antarctica was really a verdant paradise 3 million years ago. Even if global warming were occurring, it would, therefore, appear doubtful that such a deluge could be expected. That leaves us with the evidence that the bases of West Antarctic ice sheets are melting. The problem is that heavy layers of ice, possibly combined with friction from an uneven topography can cause warm-based ice. The outflow from the warm-based ice carries more ice with it, leaving them to drop in the ocean where they move southward and melt. There is no evidence of global warming in this situation and, according to Dr. Ackert of the Woods Hole Oceanographic Institution, this process has been going on for 10,000 years with the oldest ice-free beach abutting the Ross Sea becoming clear about 7,600 years ago and continuing to decay at about 120 meter per year. Thus, the phenomenon appears to have no connection with the actions of mankind - and will probably take at least another 7,000 years before the Antarctic glaciers completely melt away and the ocean rise the projected amount - regardless of the activities of mankind, who was hardly putting out large doses of Carbon Dioxide 100 years, much less 7,600.
There is no undeniable evidence that temperatures are increasing. Further, there is no evidence that mankind is responsible. Finally, there is no evidence that even if global warming is occurring it would result in a melting of the Antarctic ice sheets, whereas the Greenland Ice Sheets would only marginally increase the depth of the oceans. Perhaps the best case to be made for vastly increasing the burden on consumers of products directly or indirectly related to the production of carbon dioxide and other greenhouse gases is: "despite any real evidence, what if."
2Wallace Broeker, mentioned later in this essay, developed the theory of current flow and hypothesized that the change in ratio could shut down the current flowing between Europe and North America, allowing American cold fronts to move into Europe and greatly decreasing the temperatures in Europe. 3Some have even predicted the existence of a continuous Superstorm or ultra-hurricane in the Atlantic - or a total planetary freeze as occurred 600 million years ago, leaving the entire planet, including the oceans, surrounded by a thick layer of ice for 10 millions of years. Of course, part of the problem, as stated by Dr. Hoffman, geologist, and Dr. Schrag, geochemical oceanographer, of Harvard, is that the Sun was 6% cooler at that time in the history of the solar system than it is today and the continents were clustered at the equator, affecting the concentration of Carbon Dioxide in the atmosphere. 4While his research only relates to the continental US, it is interesting to note that some members of the International group responsible for deciding whether or not global warming is occurring have used the change in temperature variation in the Northeastern United States! to make their argument. Further, not all of the global research is completely reliable and was not evenly spread over the globe. 5Christy has subsequently stated that there might be an associative effect between the surface and the lower atmosphere such that as the surface warms up, the atmosphere cools off; however, this appears to contradict his evidence regarding surface and atmospheric temperature changes during El Nino and the Mt. Pinatubo explosion. 6Harwood also found beech trees fossils, but they appear to have been undatable and may have been from a much earlier period in time, when Antartica had not moved to its present location.
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