Climate Condition of Last Deglaciation - Research Paper Example

? Climate Condition of Last Deglaciation of Introduction It has not been easy to understand event’s sequences duringthe last deglaciation and due to this challenging tasks, scholars have come up with theories and various explanations in trying to explain and give evidence to the process which lead to formation of scablands. Such theories however will need to prove themselves against scientific evidences for them to be merited and accepted. The study has been very instrumental in understanding climate variations and how the earth’s climate is subject to change from one state to the next (Marcussen, 1977). Significantly, there has been an effort made to understand regional changes which provide evidence or relationship between the theories and various climatic variables. Scientific evidence on the Process That Lead to Formation of Scablands Scablands are formed as a result of geological erosion which sweeps the surface of the earth as a result of floods or overflows. Scablands were common in the state of Washington during the Missoula floods that periodically swept across the Eastern Washington down to the Columbia River. Scientists have provided evidences that assist in explaining the causes and the process which lead to formation of the scablands. Some of the scientific evidence include; magafloods of the ice age. This occurred about 15,000 years ago when the millennia ice age in a lake called Missoula burst suddenly through an ice dam on one end. The process was so radical which lead to a collapse sending amount of water equivalent to 500 cubic miles cascading over the Northwest pacific. This swept mass covering of the land and the surface leaving behind some unusual landscapes like the scablands of Washington State. Normally this kind of explosion is caused by turbulent forces which move tremendously in the water thus lifting large objects into the surface. It comes with a lot of particles which are thrown out of water over a great magnitude. When this happens, it results to huge sweep which fatally erodes the surface leaving behind scablands. The sweeping carried large animals like mammoths; this was evident as their vertebrate bones were found in deposits. It is still unclear whether human beings were subsequently affected because up to date, no human bone has been found in the deposits (Jeffrey, 2005). If they existed in the same habitat, chances are that, they were also damaged by the flood. Although this era was frequented by multiple floods, they were not huge as the explosion which caused the scablands. There were big floods enough to do significant erosion with huge heaps of deposition; this is because for this activity to be carried out there has to be some very high force or threshold behind the activity. It still remains unclear whether there was a single flood or multiple floods that occurred or accumulated over the last 15,000 or so years. The second evidence of formation of the scabland is the Columbia River and the Niagara falls. Scientists have given evidence about the formation of the Scablands as a result of the steep slides caused by waterfalls which create large gravel deposits resulting from splashes of water. When the rivers overflowed, they piled huge land islands which can be evidently seen protruding on the landscapes of the scablands. These show that, the streamlined features must have been carved by massive water torrents from the falls (Officer, 1994). This scientific evidence builds on the Megafloods which were the initial cause for the formation of the Scablands. The waterfalls acted as the major drainage of the glacial lake which later resulted to the Megafloods. How scientific evidence is used to reconstruct the Last Deglaciation Conditions The scientific evidences have been very instrumental in reconstruction the last deglaciation because, they give predictions as to what might happen based on the past experience. Using the weather patterns, climatic conditions of the past thousands years can be studied and subsequently predictions can be made for years to come. There has been reconstruction of qualitative stations databases about the rainfall depth and infiltration on the earth. The snowfall and snow depth has also been studied and this has assisted in rainfall reconstruction (Bruce, 2006). This has assisted in predicting the winter and summer patterns which assist in knowing climate variability of a region. Because of this reconstruction, scientists have been well equipped with measures to counter adverse weather effects which can be caused by the changes in place. Take for example, if the Mega floods of the ice age were to occur today, there will be devastating effects on the people and major towns which have been constructed along the areas which are likely to be affected by Missoula flooding. Today, there can not be such huge flooding because, as evident in the past occurrences, the flooding was caused by extremely large ice sheets which hardly exists today. When there are large ice sheets, there is a lot of water and huge volumes that the ice sheets hold. When they melt they end up releasing large volumes which causes mega floods like the ones which occurred during the time of Pleistocene. Today, the only ice sheets that exist are found in the Antarctica and Greenland, they almost cover landmasses and as such, no marginal ice lakes exists except some minor sub-glacial lakes. The fact that there are no megafloods does not leave out their chances of occurrence (Sean, 2004), subsequently, there has been some preventive measures for protecting people against any occurrences of big subglacial lakes which can as well release much floods. As a result, there have been perimeter walls constructed in major areas which experienced the floods which are specifically constructed to deal with any other related experience which might happen in the future. Whether Scientific Studies Support Scientific Evidences Presented Scientific studies have to a great extent supported the scientific evidences presented in the studies. It is evident from the scientific studies that; there existed major ice sheets which as a result of climate change, have been increasingly reducing in volume. Before the occurrences of the magafloods, there were large ice sheets which study reveals that were then broken into two ice sheets which still remains occupying major parts of the Antarctica and Greenland. Had it not been for the Megafloods, there could be a looming danger of the erosion because today there has been increased global warming which gradually melts the ice. Scientific study also supports the deposition of layers of sand which later form Scablands. It is argued that, when large deposits which are of fine particles are deposited over a considerably long period of time, scablands are created. The layers are usually known as the sea floors or lake varves (Flavio, 2004). According to studies, these layers can be used to record winters and summers, usually cold or warm summers appear in layers which are pale and thinner or thicker than most. When a streak of thin pale rock is seen in the middle of a dark winter’s layer, the lake’s midwinter memory is seen and estimated. There has been debris of wild animals, birds and other creatures found in the layers, this show prove of existence of ancient beings. According to study, no such fossils in Missoula were found and this gives room for doubt in the Megaflood theory. To some extent, the scientific study sheds light in areas where there may be doubts. This however does not mean that, all the facts presented by scientific evidences are false; some are true while others can be challenged. According to scientific study, the land’s surface is basically flat underlain by an extensive and thick basalt flows (Vincent, 1996). The braided pattern of the channels therefore supports the idea behind the erosion or the waterfalls; it shows that, there must have been some action which interfered with this natural process altering the earth’s surface. This gives room for the scientific evidences. From the bedrock that remains evident to date, the megafloods theory becomes even more practically supported by scientific studies. It is important to note that, not all scientific evidences are supported by scientific study. According the scientific study, it is possible that the scablands were formed as a result of the existing small rivers which were within the region. Instead of the Megafloods, it has been proved that over a long duration of time, the small rivers could have swept away and carved out scabland instead of the Megafloods, this challenges the scientific evidence based on the megafloods (Dean, 2006). Therefore, it is important to make further study to establish the real cause of the formation of Scablands. Pitfalls for using the scientific Evidences for Reconstruction of Paleoclimates Given the climatic change which has since occurred, it is unprintable to use these scientific evidences because they are no longer applicable today. It is also important to note that, even the major ice sheets today does not exist because of the global warming. It is therefore very difficult to experience Megafloods today. As a result of these differences, it is impossible to reconstruct Paleoclimates using the ancient scientific evidences. The ancient scientific evidences were majorly based on dissolution of major ice sheets which in turn lead to floods. These has not been happening today, because, the ice sheets have been consistently been reduced by global warming effects. It is therefore very difficult to experience major floods like the ones that happened which lead to development of the evidences. Global warming has also restructured the climatic patterns, it is no longer predictable or stable, and this makes it very difficult to use the scientific evidences for reconstructing paleoclimates. The time variations would make predictions inaccurate and untrue. This is another problem of using predetermined scientific evidences. As seen above, not all scientific evidences can be supported by scientific studies, this gives room for doubt and as such, they cannot be accurately applied in reconstruction of Paleoclimates (William & Wright, 1987). This is because, some scientific evidences are just theories and they cannot be proven and applied successfully. It is also evident that, most scientists developed their facts on estimations. There is therefore no correctness of the graphs and statistics estimating temperature records. When these records are then used to convey complex results and science to the public, there arises a question of their robustness of facts presented. This has thus been a major pitfall in using these scientific evidences. There is another major challenge of using, scientific evidences, particularly when studying climate patterns. Most scientists reconstructed a hemispheric-scale against which subsequent analysis and measurements were to be used to record temperature change, this was not effective given that, the data backdated to 1400 could be less applicable today. The scale was also reconstructed after a series of measurements implying that, it is not a hundred percent accurate. This has been a great challenge and question as to whether to use scientific evidences in Reconstruction of paleoclimates. The fact that there are changes and that what happened long ago is less likely to happen because of the global warming and changes in temperatures, it is evident that unless new innovations are made, scientific evidences cannot be used in the recent reconstruction of paleoclimates. Conclusion It is evident that, during deglaciation, the southern and the Northern hemispheres are the most affected regions, this is because; these regions experience diverse and extreme temperature variations. Regions which are sea-ice covered also experience the same. It is also proven that, using long averages, climate change can be anticipated though not in exactness. This is because, deglaciation is caused by varying factors which keep on changing and are thus not predictable. References Arhcer, D. (2010). The Climate Crisis: An Introductory Guide to Climate Change. Cambridge: Cambridge University Press. Bruce, B. (2006). On the Trail of the Ice Age Floods: A Geological Field Guide to the Mid- Columbia Basin. Columbia: Keokee books Publishers. Dean, A. (2006). Restoring the Pacific Northwest. Boston: Island Press Publishers, Flavio, J. (2004). The Influence of Glacial Boundary Conditions on the Climate System during the Last Glacial Maximum. Germany: Sharker Verlag Gmbh Publishers. Jeffrey, A. (2005). Crops and Environmental Change. CRC Press Publishers, Marcussen, I. (1977). Deglaciation landscapes formed during the wasting of the late Middle Weichselian ice sheet in Denmark. Denmark: C.A Reitzels Publishers. Officer, C. (1994). Tales of the Earth: Paroxysms and Perturbations of the Blue Planet. Oxford: Oxford University press Publishers. Sean, D. P. (2004). J Harlen Bretz and the Great Scabland Debate. Retrieved from http://www.detectingdesign.com/harlenbretz.htm Vincent, B. (1996).Postmodernism-Local Effects, Global Flows: Local Effects, Global Flows. New York, NY: State University of New York Press Publishers. William, F & Wright, H. E (1987). North America and Adjacent Oceans during the Last Deglaciation. Boston: Geological Society of Amer Publishers. Read More