РефератыИностранный языкA A Guide To The End Of The

A Guide To The End Of The

World Pt 2 Essay, Research Paper


A Guide to the End of the World pt 2Of all geological hazards, landslides are perhaps the most


underestimated, probably because they are often triggered


by some other hazard, such as an earthquake or deluge, and


the resulting damage and loss of life is therefore subsumed


within the tally of the primary event. Nevertheless, landslides


can be highly destructive, both in isolation and in numbers.


In 1556, a huge earthquake struck the Chinese province of


Shensi, shaking the ground so vigorously that the roofs of


countless cave dwellings collapsed, incarcerating (according


to Imperial records) over 800,000 people. In 1970, another


quake caused the entire peak of the Nevados Huascaran


mountain in the Peruvian Andes to fall on the towns below,


wiping out 18,000 people in just four minutes and erasing all


signs of their existence from the face of the Earth. Heavy


rainfall too can be particularly effective at triggering landslides, and when in 1998 Hurricane Mitch dumped over 30


centimetres of rain on Central America, it mobilized over


a million landslides in Honduras alone, blocking roads,


burying farmland, and destroying communities. The final – and perhaps greatest – threat to life and limb


comes not from within the Earth but from without. Although


the near constant bombardment of our planet by large


chunks of space debris ended billennia ago, the threat from


asteroids and comets remains real and is treated increasingly


seriously. Even as I write, the UK government has announced


funding for a new research centre dedicated to the study of


the impact threat and its consequences. Recent estimates


suggest that around a thousand asteroids with diameters of


1 kilometre or more have orbits around the Sun that cross


the Earth’s, making collision possible at some point in the


future: 1 kilometre is the impactor diameter threshold for


initiating a cosmic winter, due to dust lifted into the stratosphere blocking out solar radiation, for wiping out a quarter


or so of the human population, and for causing general


mayhem worldwide. The revival of interest in the impact


threat has arisen as a result of two important scientific events


during the last decade: first, the identification of a large


impact crater at Chicxulub, off Mexico’s Yucatan Peninsula,


which has now been established as the ’smoking gun’


responsible, ultimately, for global genocide at the end of


the Cretaceous period: second, the eye-opening collisions


in 1994 of the fragments of Comet Shoemaker-Levy with


Jupiter. Images flashed around the world of resulting impact


scars larger than our own planet were disconcerting to say


the least and begged the question in many quarters – what if


that were the Earth? Natural hazards and usIf you were not already aware of the scale of the everyday


threat from nature then I hope, by now, to have


engendered a healthy respect for the destructive potential


of the hazards that many of our fellow inhabitants of planet


Earth have to face almost on a daily basis. The reinsurance


company Munich Re., who, for obvious reasons, have a considerable interest in this sort of thing, estimate that up to 15


million people were killed by natural hazards in the last


millennium, and over 3.5 million in the last century alone.


At the end of the second millennium AD, the cost to the


global economy reached unprecedented levels, and in 1999


storms and floods in Europe, India, and South East Asia,


together with severe earthquakes in Turkey and Taiwan and


devastating landslides in Venezuela, contributed to a death


toll of 75,000 and economic losses totalling 100 billion


US$. The last three decades of the twentieth cen

tury each saw a


billion or so people suffer due to natural disasters. Unhappily, there is little sign that hazard impacts on society have


diminished as a consequence of improvements in forecasting


and hazard mitigation, and the outcome of the battle against


nature’s dark side remains far from a foregone conclusion.


While we now know far more about natural hazards, the


mechanisms that drive them, and their sometimes awful consequences, any benefits accruing from this knowledge have


been at least partly negated by the increased vulnerability of


large sections of the Earth’s population. This has arisen primarily as a result of the rapid rise in the size of the world’s


population, which doubled between 1960 and 2000. The


bulk of this rise has occurred in poor developing countries,


many of which are particularly susceptible to a whole spectrum of natural hazards. Furthermore, the struggle for


Lebensraum has ensured that marginal land, such as steep


hillsides, flood plains, and coastal zones, has become increasingly utilized for farming and habitation. Such terrains are


clearly high risk and can expect to succumb on a more frequent basis to, respectively, landsliding, flooding, storm


surges, and tsunamis. Another major factor in raising vulnerability in recent


years has been the move towards urbanization in the most


hazard-prone regions of the developing world. Within just a


few years, and for the first time ever, more people will live in


urban environments than in the countryside, many crammed


into poorly sited and badly constructed megacities with populations in excess of 8 million people. Forty years ago New


York and London topped the league table of cities, with


populations, respectively, of 12 and 8.7 million. In 2015,


however, cities such as Mumbai (formerly Bombay, India),


Dhaka (Bangladesh), Karachi (Pakistan), and Mexico City


will be firmly ensconced in the top ten: gigantic


sprawling agglomerations of humanity with populations


approaching or exceeding 20 million, and extremely vulnerable to storm, flood, and quake. A staggering 96 per cent of


all deaths arising from natural hazards and environmental


degradation occur in developing countries and there is currently no prospect of this falling. Indeed, the picture looks as


if it might well deteriorate even further. With so many people


shoehorned into ramshackle and dangerously exposed cities


it can only be a matter of time before we see the first of a


series of true mega disasters, with death tolls exceeding one


million.The picture I have painted is certainly bleak, but the


reality may be even worse. Future rises in population and


vulnerability will take place against a background of dramatic climate change, the like of which the planet has not


experienced for maybe 10,000 years. The jury remains out


on the precise hazard implications of the rapid warming


expected over the next hundred years, but rises in sea


level that may exceed 80 centimetres are forecast in the


most recent (2001) report of the IPCC (Intergovernmental


Panel on Climate Change). This will certainly increase


the incidence and impact of storm surges and tsunamis


and – in places – raise the level of coastal erosion. Other


consequences of a temperature rise that could reach 6


degrees Celsius by the end of the century may include


more extreme meteorological events such as hurricanes,


tornadoes, and floods, greater numbers of landslides in


mountainous terrain, and, eventually, even more volcanic


eruptions. So is the world as we know it about to end and, if so, how?


A century from now will we be gasping for water in an


increasingly roasting world or huddling around a few burning sticks, struggling to keep at bay the bitter cold of a cosmic


winter?

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