Global Warming


 


A current book by Lovelock (2006), provides cause to consider that disastrous consequences of global warming are much more forthcoming than is in general realised. He disputes in terms of his Gaia hypothesis (Lovelock, 1979) according to which the entirely of life in the biosphere acts in some respects like an enormous living creature, with means of modifiable such variables as the surface temperature of the earth, salinity of the oceans and oxygen content of the atmosphere, at levels well-matched with life. The hypothesis is extensively accepted and has underlain precise predictions.


Sunlight falling on land and water warmth the surface of the Earth and a few of this heat is re-emitted as radiation. In addition, Greenhouse gases suck up some of this radiation, warm the atmosphere and return some of this heat towards the surface of the Earth. The bigger the concentration of greenhouse gases in the atmosphere, the larger is the heating effect (Tisdell, 2008).


Carbon Dioxide or CO2 is one of the major greenhouse gases. From the time of the Industrial Revolution it has increased from 230 ppm in the Earth’s atmosphere to 380 ppm, it is now at levels that are much higher than have been recorded in the last 650,000 years (Pachauri, 2007). Even if CO2 emissions are maintained at the current levels, the concentration of CO2 in the atmosphere will still increase to around 525 ppm by the end of this century and global warming will speed up in the not too distant future (Tisdell, 2008).


During the last century, global warming of about 1°C on average had happened. Stabilization of CO2 emissions at the present level shows as though it could engage a global mean temperature increase of about 2.8°C, which will have very serious global environmental consequences. Globally, there is most likely little view of greenhouse gas emissions being lessened below current levels. But they may persist to increase. Carbon emissions have increased at about a constant rate in the last 50 years, and even though the degree of increase may be lessened due to the post-Kyoto global agreement, it seems too hopeful to foresee an actual decrease in carbon emissions compared to those at present (Tisdell, 2008).      


As a consequence sea levels can be expected to keep on rising. They rose on average by about 10-20 cm in the last century (Pachauri, 2007). Given current (2007) climate change policies, IPCC (2007, p. 7) estimates sea level rises in this century ranging from 0.18 to 0.59 metre. However, those figures are vague and actual sea level rises could be even higher (IPCC, 2007, p. 8). This is partly because there is a great deal of uncertainty about the extent of and the speed with which ice caps will melt in Greenland and elsewhere (UNEP, 2007, p. 64) melting of the Greenland ice sheet could result in a 7 meter rise in seal levels eventually (UNEP, 2007, p. 64). Sea-level rise is expected to accelerate. Snow cover and glacier mass balance is declining globally and contributing to increases in sea levels (Pachauri, 2007).


Consequently, geographical patterns of water availability will change in drastic manner, weather disturbances or disasters will become more recurrent and riskier, global food accessibility could decline, human habitation will become more unstable and insecure because of storms, rising sea levels and adverse weather conditions, new health risks and problems will emerge in more geographical locations (for instance, malaria could become more widespread) and substantial loss of biodiversity and ecosystems is anticipated (National Geographic, 2007, Map Supplement: Changing Climate, McKibben, 2007).


At the same time as one cannot foresee all the results of global warming with conviction, there is growing agreement amongst scientists about the major results of global warming and its causes. There is no doubt that most of Pacific Island nations will experience unfavorably from global warming and that sea-level rise will make threats on the continuing survival of some (Tisdell, 2008).


 


 


 


References


Lovelock, J. E. (1979). Gaia: A new look at life on earth. Oxford: Oxford University Press.


Lovelock, J. E. (2006). The revenge of Gaia: Why the eart is fighting back – And how we can still save humanity, with foreword by Sir Crispin Tickell. London: Allen Lane.


 


National Geographic (2007), “Changing climate”, National Geographic Magazine, map insert, Vol. 212 No.4.


Pachauri, R.K. (2007), The IPCC Fourth Assessment Working Group Reports: Key Findings, United Nations, New York, NY, Retrieved on 4th October, 2010, from www.ipcc.ch/.


Tisdell, C. (2008). ‘Global warming and the future of Pacific Island countries’. International Journal of Social Economics. Vol. 35, no. 12, 889 – 903.


UNEP (2007), “Global environment outlook”, Retrieved on 4th October, 2010, from www.unep.org/geo4/media/index/asp.



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