Global Warming Debate Essay

morepeople think that our concern nigh snow dioxide and orbicular calefacient is a modern preoccupation driven by the attention of high-profile personalities, politicians and gullible activists. But Al Gore did not discover global warming. Nor did Tim Flannery, dent Garrett, Greenpeace or Malcolm Turnbull. Scientific concern about global warming is not new. A single scientific paper, published more than three decades ago, tummy place the discussions about climate change into historical perspective.Tomorrow it lead be 35 years since the leading science journal spirit published a review paper entitled Man-make carbon dioxide and the glasshouse effect, by the eminent atmospherical scientist J. S. sawyer, director of inquiry at the United Kingdom Meteorological Office. In four pages, sawyer beetle summarised what was known about the role of carbon dioxide in enhancing the innate nursery effect leading to warming at the earths surface, and made a remarkable 28-year predict ion of the warming expect to the end of the twentieth century.His prediction can now be canvasd with what has been observed. We can in addition compare his review of the science in the early seventies with that in the a la mode(p) (2007) assessment from the Intergovernmental Panel on Climate Change. After summarising recent calculations of the apparent impact of increasing carbon dioxide concentrations on global surface temperature, sawyer concluded that the increase of 25 per cent in carbon dioxide expected by the end of the century on that pointfore corresponds to an increase of 0. degrees in founding temperature an amount somewhat greater than the climatic variations of recent centuries.Examination of the global surface temperature over the latter part of the 20th century shows that in fact the temperature rose about 0. 5 degrees between the early 1970s and 2000. Considering that global temperatures had, if anything, been falling in the decades leading up to the early 1970 s, sawyer beetles accurate prediction of the reversal of this trend, and of the magnitude of the subsequent warming, is mayhap the most remarkable long-range forecast ever made. sawyers succinct summary of the climate change science understood at that time can be compared with the four volumes of the IPCC Fourth Assessment on Climate Change being released through 2007. The IPCC assessment involves more than four hundred authors, about 2500 reviewers, and runs to several thousand pages with many thousands of references. Such a analogy shows that much has been done to address the concerns and uncertainties expressed by sawyer beetle at the time. He was concerned that the rudimentary understanding of cloud processes and other climate system feedback resulted in uncertainties regarding predictions of warming.At the time, climate models were in their infancy, but sawyer beetle saw them as the lift out way to examine this feedback and reduce the uncertainties in climate change predictio ns. Since then, models have improved substantially and now involve many more processes in more detail than was possible in the early 1970s, and the various climate processes that may enhance or set out the effects of carbon dioxide have been studied in detail. Despite these advances, our lift out assessment of the warming to be expected from a doubling of atmospheric carbon dioxide concentration has changed little from Sawyers time.Our best estimate of the temperature increase that would result from a 25 per cent increase in atmospheric carbon dioxide concentrations is still around 0. 6 degrees. The scientific consensus of Sawyers time was very similar to the scientific consensus in 2007. Of course, let on climate models and improved data and analyses have allowed the IPCC to discuss and even mould possible changes in many other meteorological variables than could Sawyer, including extreme stomach of various kinds as well as sea-level.The IPCC now also looks in detail at regi onal aspects of climate change a bow not even considered by Sawyer. Perhaps the greatest difference, however, is the emphasis on the impacts of climate change. While the IPCC assessment devotes a volume to this subject, Sawyer could all conclude, after conceding that climate variations of only a fraction of a degree can have considerable economic importance that although there may be no immediate cause for alarm about the consequences of carbon dioxide in the atmosphere, there is certainly need for further subscribe.Perusal of the IPCC volume devoted to the impacts of climate change on natural and human systems leaves one feeling far less sanguine than Sawyer was 35 years ago. The anniversary of Sawyers paper reminds us that the understanding of the effects of carbon dioxide on the global climate was sufficiently advanced 35 years ago to allow an accurate 28-year prediction of warming.Despite claims to the contrary, our understanding of the greenhouse effect and global warming i s not reliant on modern climate models and nor is it a modern preoccupation. Nor is it even out to claim that in the 1970s climate scientists were predicting global cooling Sawyers paper accurately predicted exactly the opposite, based on the best science available. Other scientific papers around that time also drew attention to the warming expected from the anthropogenic increases in greenhouse gas emissions.