ClimateChangeOver the past years most individuals have become acutely aware that theintensity of human and economic development enjoyed over the 20th century cannotbe sustained. Material consumption and ever increasing populations are alreadystressing the earth’s ecosystems. How much more the earth can take remains avery heated issue.
Here a look at the facts sheds some very dark light. In 1950,there were 2. 5 billion people, while today there are 5. 8 billion. There may wellbe 10 billion people on earth before the middle of the next century. Even moresignificant, on an ecological level, is the rise in per capita energy andmaterial consumption which, in the last 40 years, has soared faster than thehuman population.
“An irresistible economy seems to be on a collision coursewith an immovable ecosphere. ” Based on these facts alone, there is gravereason for concern. Taken further, it is even more frightening to note that,while man has affected the environment throughout his stay on earth, the impacthas been most intense in the relatively short industrial era. Since theindustrial revolution, and over the past century in particular, man’secological footprint on the earth has quickly grown from that of a child to oneof a giant.
True, this period is heralded as an economic success story, which itcertainly has been. However, many argue that it seems increasingly likely thatthe path to man’s success will soon slope downward to his demise. The climateis changing, and so must we. This paper will look at the coin of climate change,where on the one side the human impact on the earth will be shown, and on theother, the impact of earth on man.
Such a study is inevitably somewhatpolemical, as it is still open to debate what the precise effects of man haveand will be on climate change, and also what climate change will mean to man. Itwill also be quite general in analysis, as a paper of this scope can allow nomore. What will be made clear, nevertheless, is that the relationship betweenman and earth is clearly changing. More specifically, man is outgrowing theearth. If the relationship is to continue?indeed prosper?then a new balanceneeds to be found.
The issue of climate change holds one important key to thisbalance. Man and the Environment Thomas Malthus is well remembered for hisposition as a doomsayer. When looking at the rates of population growth inVictorian England, he saw unchecked growth as leading to a rapid decline in theliving standards of man. He blamed this decline on three main factors: theoverproduction of offspring; the inability of natural resources to sustainrising human population; and the irresponsibility of the lower classes toprevent their overpopulation. Very generally, Malthus suggested that this trendcould be controlled only if the family size of the lower classes was regulatedso that poor families would not produce more children than they could support.
He predicted that the demand for food would inevitably become far greater thanthe available supply of it. This prediction was rooted in the thought thatpopulation, when unchecked, increased geometrically; i. e. , 2,4,8,16,32. . .
whilefood products, or as he called it ?subsistence’, only grew at an arithmeticrate; i. e, 1,2,3,4,5,. . .
. . . He provided only a basic economic reason for thishowever, and generally attributed famine, poverty and other catastrophicoccurrences to divine intervention (he was a very religious man, a clergyman, infact). He believed that such natural outcomes were essentially God’s way ofpreventing man from being lazy.
The point here is not to provide an evaluationof Malthus, and one might well argue that he was wrong in many of hispredictions; but rather to highlight the posit that man has long been livingbeyond his means. Sooner or later, this will have its consequences. As aspecies, our success has certainly been impressive, but it has come by turning ablind-eye to our surroundings. “A prime reason for our success is ourflexibility as a switcher predator and scavenger.
We are consummately adaptable,able to switch form one resource base?grasslands, forests or estuaries?toanother, as each is exploited to its maximum tolerance or use up. Like othersuccessful species we have learned to adapt ourselves to new environments. But,unlike other animals, we made a jump from being successful to being a runawaysuccess. We have made this jump because of our ability to adapt environments forour own uses in ways that no other animal can match. ” Whether or not man cancontinue to adapt to the emerging environment, however, is a difficult question.
In a (literally) rapidly changing world, it is difficult to look back on past orpresent to divine the future. But, using Malthus’ line of reasoning, one wayor another mother nature will surely ?take care of us’. “Lack ofresources, environmental degradation, famine and disease will in the painfulfashion known by our ancestors cut our species back. AIDS is the obvious exampleof a way in which to do it. .
. . Conditions already exist in several Africancountries for the virus to kill more people than are being born. . .
However, withits incubation period of as much as ten years or even more, AIDS is not aboom-and-bust infection like the Black Death. Unchecked it could move on atime-scale of 200 rather than 20 years. But the effects could be asdevastating. ” It is thus clear that we can not go on as we have in the past. The questions of ?when’ and ?how’ environmental degradation will catchup with us remain. In passing, it should be noted that there are several (weak)arguments to be made suggesting the patterns of climatic change that have, andwill still, occur to be quite beyond the understanding and influence of mortalmen.
As argued by C. W. Thornthwaite in 1956, “man is incapable of making anysignificant change in the climatic pattern on the earth; that the changes inmicroclimate for which he is responsible are so local and some so trivial thatspecial instruments are often required to detect them. ” Another interestingargument against the severity of global warming, forwarded by Meyer in 1996, isthe “artefact of a transition of stationing weather observatories near citiesthat have grown considerably during the same period. And place this curve, withits relatively small fluctuations, net to one of natural temperature changesover the last 20,000 years, and one might well despair of hearing any humanimpacts against so noisy a background.
” These arguments bring to light thecontroversy that surrounds the urgency of global warming and climatic change. Indeed, standing alone they do make compelling assertions that can only becountered by the application of theory. As also noted by Meyer, “only byadding a theoretical explanation of the workings of the climate system, theprocesses that generate the events that we experience as weather and the orderthat we discern as climate, can we suggest with some confidence what would havebeen or would be the consequences of particular human activities. ” TheImportance of Environmental Viability Before moving on, it is necessary tohighlight the importance of environmental viability. While this may already bewell known, it is equally apparent that most individuals do not perceive it asan immediate problem.
For most, concern with the environment is a distantlong-term problem that does not require today’s attention. This has much to dowith the lifestyle that has created the problems in the first place. In ourincreasingly interlinked world there is a common strive towards a ?global’economy which is characterised by the swelling of liberalised trade andfinancial capital flows. Though it is not certain at this point where this willlead, it is very likely that the result will be increased economic activity and,in turn, increased material and resource consumption. For many, at least in thedeveloped world, this means increased prosperity and enhanced standards ofliving. The glamour of this lifestyle, however, tends to hide the ugly facts.
Consider, for instance, that already at this stage of development, “rates ofresource harvesting and waste generation deplete nature faster than it canregenerate. . . . As the world becomes ecologically overloaded, conventionaleconomic development actually becomes self-destructive and impoverishing.
Manyscholars believe that continuing on this historical path might even put our verysurvival at risk. ” In contrast to the impressions of many, the environment isan immediate problem. Though environmental concerns are widespread and many,perhaps the most challenging is the significant (30%) increase in greenhousegasses accumulated in the atmosphere since the industrial revolution. At presentrates of increase, these greenhouse gasses will again double by the turn of thenext century. The effects this will have on the earth’s climate remaincontroversial, but most agree that the earth’s equilibrium temperature will beaffected.
The argument here remains, how much? This question will be looked atin the forthcoming section. Climatic Change It is not surprising to note at thisstage that “fluctuations and changes in climate occur both spatially andtemporally, the causes of which are a source of much speculation andcontroversy. What is unequivocal is that the past 2 to 3*106 years (and more)have been characterised more by change than by constancy. It is equally apparentthat climatic change, whether it is a response to natural or cultural stimuli,is complex. It is not yet understood which factors, either singly or incombination, create positive feedback, nor is it understood how theyinteract. ” Even further, the indices of climatic and environmental change overthe past 2 to 3*106 years have been proxy records, which makes theidentification of their underlying causes a formidable task.
Having noted theseinherent problems, its is possible to objectively evaluate some of thepredictions that have been forwarded over time. There are several ways by whichclimatic change can be recorded and understood. Three of the most well known arequaternary subdivisions based on the terrestrial record, ocean sediment cores,and ice cores. These methods have been used in isolation and also in conjunctionwith one another. Of particular interest here is the growing body of data thathas been collected from ice cores that is contributing to studies ofenvironmental change and aiding correlations between polar, continental andocean sediment records.
“The polar ice sheets and those of high tropicalmountains are nourished by precipitation from the atmosphere, the composition ofwhich is thus recorded as successive layers of ice accumulate. Such recordsprovide information on environmental change over the past ca. 200K years andbase line data from pre-and post-industrial levels for the biogeochemicalcycling of metals such as lead. ” Over the past century, countless theoriesabout climate change have been advanced and tested using the above techniques. First to be highlighted are those that look at climatic change as part of asystem of internal adjustments within the climatic system. “Several haveemphasised changes in the quantity and quality of solar radiation, especially inrelation to sunspot cycles.
. . Currie’s (1995) identification of the 18. 6 yearlunisolar cycle and the 11 year solar cycles in Chinese dryness/wetness indices,for example. ” Such phenomena have been associated with floods, draughts, poorharvests, and the like.
A 1988 study by Labitzke and Loon made a connectionbetween sunspot maxima/minima and quasi-biennial oscillation (QBO). “The QBOis an oscillation of the zonal wind component in the stratosphere above theequatorial region with a periodicity of ca. 27 months. ” Their study over a 36year period pointed out a positive link between “warmer winters during theSun’s more active periods and between colder winters when the Sun is leastactive and when the QBO is in a westerly direction. ” They found that thereverse conditions also applied.
While this relationship has subsequently beencriticised and generally disrespected, recent polar ice core samples have indeedshown correlations consistent with the study. Indeed, a 1990 study by Beer et allinked “10Be deposition with the 11 year sunspot in Dye 3 ice core fromGreenland. Beer et al. state that increased levels of 10Be occur when solaractivity declines; and because the intensity of the solar wind is reduced thereis an increase in the generation of cosmogenic isotopes such as 10Be and 14C. “Another 1990 study by Wigley and Kelly not only fortifies but also adds to thesefindings. “Not only is there a relationship, albeit complicated by the effectsof precipitation, between the 10Be in the Vostok ice core and temperaturechange, but there is also a possible relationship between the 14C concentrationsand fluctuations in glaciers.
The nature of this relationship and the way itvaries have yet to be determined; for now, change in solar irradiance, aliassunspots cycles, remain as enigmatic as ever. ” Tree ring data has also beenhelpful in the study of natural climatic change. In addition to the variablesjust noted, there are researchers who believe that the quantity and quality ofsolar radiation that reaches the earth is mainly affected by dust and sulphateaerosols, usually concomitant to volcanic eruption. “The dust scatters andpartially reflects incoming solar radiation whereas the aerosols act ascloud-condensation nuclei. Both cause reduced temperatures for short-livedperiods unless the volcanic eruptions are very large. ” Tree ring evidence hasfound that cool summers since the 17th century have indeed been primarily due tovolcanic eruptions.
Volcanic eruptions can further influence climate by theirpollution of the oceans. “some of the dust will settle into the water body,providing nutrients such as iron and other cations, which may stimulate primaryproductivity in maine phytoplankton. Their uptake of carbon dioxide could reduceits concentration in the atmosphere and contribute to global cooling bydiminishing the greenhouse effect. ” There can be little doubt that thecombination of these, and various other factors, does induce a varying degree ofcyclical climatic change. However, some suggest that none of them contributesufficiently to create positive feedback that would effect changes in themagnitude of glacial-interglacial swing. “It is now widely accepted thatastronomical forcing, the Milankovitch theory, is the most important primarycause of Quaternary glacial-interglacial cycles and probably those of earliergeological periods.
. . . It is the change in the orbital eccentricity that isthought to drive the glacial interglacial cycle. These cycles influence theamount of solar radiation received at the Earth’s surface, especially in thehigh latitudes of the northern hemisphere. ” However, these cycles have provento have little effect on insolation.
Other non-naturally occurring factors aretherefore responsible for the climatic changes anticipated. Popular causes arethe greenhouse gases, notably carbon dioxide and methane, whose changes inatmospheric concentration parallel global warming and cooling. Further, theremay also be a relationship between “ocean circulation, atmosphericconcentrations of greenhouse gases and global temperature change. The productionand dampening of North Atlantic Deep Water in particular is considered to be amechanism whereby temperature change over the Arctic ice cap is translated intoglobal change.
” Whatever the particular cause of climatic change, whatinterests many observers is how the changes will impact on human existence. Itis reasonably safe to say that, in aggregate, the changes will be large andprofound. Indeed, it is quite possible that human life and ecosystems in someparts of the world will not be able to survive. In all likelihood, the change isprobably going to be a reasonably quick one, occurring perhaps within decades,and most certainly within a century. “Across the globe, changes in temperaturewould be reflected, in complex ways, in the migration of rainfall patterns, withenhancement in some areas and drying in others.
Short-term weather events mightbecome more variable and severe and unusual storms occur more frequently. Forests, sensitive to temperature, might be severely damaged if the rate ofwarming exceeded the rate at which the forest species could migrate toward moresuitable conditions, and such migration would be widely obstructed where otherland uses stood in the way. ” Moreover likely is that the melting of the polarice caps would cause the sea level to rise. While some credible argumentsactually suggest that the sea level would decrease (due to increasedprecipitation in the polar regions), the mainstream logic does rather suggest arise to the tune of several centimetres per decade. In time, this would surelyflood very low-lying coastal areas, and increase erosion and stress onshorelines around the world.
This knowledge, however, is of little comfort orinterest to most people. The only fact that can perhaps involve people and easetheir tensions is knowing which particular locations will be affected, and howthey can begin to prepare themselves. It is towards this difficult question thatthe following question turns. Regional and Local Effects of Climate ChangeMaking any specific or even generalised claims about regional and local climatechanges is even more controversial than the effects of climate change at large.
“Existing lakes and inland seas do have some measurable effects on temperatureand humidity in the ribbon of land along their shores, but no so large and sowidespread as ordinarily to justify creating new ones as climatic generators. “The same type of controversy surrounds the desertification of land. Looking tothe cases of the desertification of the middle east, northern Africa, and India,it is argued that “overgrazing by livestock both raised the albedo of thesurface and injected dust into the air; thus altering the regional heat balanceby reflecting away more solar radiation. A net cooling from these processes thenpromoted atmospheric stability and suppressed rainfall; the vegetation witheredunder the lessened rainfall and more dust swirled upward, magnifying theoriginal impact. ” The example of the diminishing rainforests provides anothergood, though controversial, case. As has been witnessed in these regions to somedegree, changing the earth’s physical landscape can have affects onmicroclimates.
Cities, too, have witnessed some significant climatic changes asa result of increased urbanisation. The well-known ?heat island’ effect;i. e. , a net elevation of temperatures above those found in the adjacentcountryside, has been well documented.
“It stems particularly from changes inthe land surface and the energy budget. Cities themselves generate much of theheat in which they bask or swelter. The roughness of the urban land surfaceretards the speed of the winds, and thus lessens the dispersion of heat; theimpermeable and well-drained surface is less moist, and so less heat is lostthrough evaporation; and the structures and surfaces typical of the city absorband retain heat at high rates. ” This increased heat may in turn result in fog,storms, precipitation induced by convective heating and pollution condensation. On a larger regional level, the distribution of species will be affected byclimatic change, which is likely to have widespread consequences for human life. Agricultural pests will be displaced, and the incidence of ?disease vectors’through the spread of malaria carrying mosquitoes, for instance, will affect thehealth and well-being of human populations.
Mannion makes the observation that”areas of high altitude are those which have been most directly affected bythe advance and retreat of glaciers and ice caps. Indeed, the Arctic andAntarctic zones are currently experiencing glaciation, and it is from theseareas that much can be learned about glaciation. ” Many others share this positthat higher altitude will be more affected, but how much more remains thequestion. In sum, it must be said that “the diversity of the earth’s surfacetranslates into a diversity of physical impacts of global changes, differentsocial impacts even of similar physical ones, different expectations of theirimpacts?which , of course, have often been wide of the mark?and differentcosts that any globally uniform change in behaviour would incur. ” Based onthis observation, it is quite likely that landlocked countries have nothing tofear in terms of rising sea levels, and areas that have traditionallyexperienced poor levels of rainfall may actually benefit from increasedprecipitation. Canada, however, as a nation that is very dependent onagriculture, forestry, and fisheries?and thus more dependent on climaticconditions?will likely be quite vulnerable to any climatic shifts.
In general,however, it can be said that “climate change may create opportunities for gainas well as for loss, but countries with different endowments of skills andcapital will differ in their ability to exploit those opportunities. “Conclusion As has been advanced throughout this paper, there is a considerabledegree of uncertainty surrounding the climatic future of the earth. This,according to Mannion, “highlights the complexity of the climate system and theinadequacy of current scientific understanding. ” This vein of thought also ranthrough the Rio Earth Summit, which recognised the reality of global warming,but also the substantial scientific uncertainty with regard to its timing andmagnitude. This lingering confusion has made the problem of global environmentalchange “the largest single problem facing the world scientific community.
“But, while the precise impact of man’s footprint on the earth cannot bemeasured with great accuracy, there is no reasonable man who will argue thatcurrent rates of consumption are either beneficial or wholly necessary. Indeed,it is quite intuitive to conclude that increasing industrialisation andincreased economic output is a step in the wrong direction, at least in terms ofthe environment’s wellbeing. Given the state of present day research, it hasreasonably been estimated that “under a business as usual scenario ofcontinued growth of fossil fuel use, and hence of greenhouse gas emissions, theglobal average temperature is estimated to rise at a rate close to 0. 3C perdecade?a rate which is probably greater than any that has occurred on earthsince the end of the last ice age, some 10,000 years ago.
Associated with therise in global average temperature will be substantial changes in regionalclimate, especially in the intensity and frequency of droughts and floods. “Though impossible to prove, in aggregate it has been argued that the change willbe large and greater than the earth has seen since the last ice age. If this iseven close to the truth, it is very likely that human beings and the earth’secosystems will not be able to sustain the pace of change in their presentsurroundings. What will happen at the regional and local level, however, is muchmore difficult to predict though in some cases, will likely be even moredevastating.
From what has been shown in this paper, there is distinct reason tosuspect that higher latitudes will experience greater overall warming than lowerlatitudes. If this is indeed the case, “the release of vast stores of carbonfrom the tundra peatlands and boreal zone will reinforce global warming. Moreover, if there are further reductions in acidic emissions, which at currentlevels cause a counteracting effect, global warming will be accelerated. ” Putsimply, this is not a good thing. Quantifying the extent of the potential damageis not only beyond the scope of this paper, but perhaps beyond humancomprehension (at this point) and even worse, missing the point.
The onlycertainty about future climatic change is indeed uncertainty of its extent. Itmight not be wrong, given such circumstances, to prepare for the worst. Thepicture that this study has painted is, quite apparently, confusing and sombre. However, there is a faint stroke of optimism that can be added. E.
G. Nisbetnotes that “despite our losses, we are intellectually and physically richerthan any other generation of humanity. Our poverty is spiritual. It is wellwithin our power to be optimists, if we can dispel the cynicism of the pastdecades. If we are optimists, most things are possible.
The challenge to cherishthe planet, to construct a new global economy, is far less than the challenge,in 1940, to defeat the last threat against human hope. ” This strain ofreasoning provides a welcome contrast to the depressing observation noted byBarrett at the opening of this study. And it is true, there is nothing tosuggest that we are firmly locked into a future that is condemned. For the firsttime in history, it may well be possible for a balance to be found between manand nature. BibliographyArcher, Eileen (1994) People and the Environment: Preserving the Balance,London: Association of Commonwealth Universities Goulde, Andrew (1997) The HumanImpact Reader, Oxford: Blackwell Publishers Mannion, A.
M. (1997) GlobalEnvironmental Change: A Natural and Cultural Environmental History, New York:Longman Press Meyer, William B. (1996) Human Impact on the Earth, Cambridge:Cambridge University Press Nisbet, E. G. (1991) Leaving Eden: To Protect andManage the Earth, New York: Cambridge University Press Wackernagel, Mathis.,Rees, William (1996) Our Ecological Footprint: Reducing Human Impact on theEarth, Philadelphia: New Society Publishers Westphal, Dale., Westphal, Fred(1994) Planet in Peril, Toronto: Harcourt Brace
