3.Ships in the Desert
I was standing in the sun on the hot steel deck of a fishing ship capable of processing a fifty-ton catch on a good day. But it wasn' t a good day. We were anchored in what used to be the most productive fishing site in all of central Asia, but as I looked out over the bow , the prospects of a good catch looked bleak. Where there should have been gentle blue-green waves lapping against the side of the ship, there was nothing but hot dry sand – as far as I could see in all directions. The other ships of the fleet were also at rest in the sand, scattered in the dunes that stretched all the way to the horizon . Ten year s ago the Aral was the fourth-largest inland sea in the world, comparable to the largest of North America's Great Lakes. Now it is disappearing because the water that used to feed it has been diverted in an ill-considered irrigation scheme to grow cotton In the user t. The new shoreline was almost forty kilometers across the sand from where the fishing fleet was now permanently docked. Meanwhile, in the nearby town of Muynak the people were still canning fish – brought not from the Aral Sea but shipped by rail through Siberia from the Pacific Ocean, more than a thousand miles away.
My search for the underlying causes of the environmental crisis has led me to travel around the world to examine and study many of these images of destruction. At the very bottom of the earth, high in the Trans-Antarctic Mountains, with the sun glaring at midnight through a hole in the sky, I stood in the unbelievable coldness and talked with a scientist in the late tall of 1988 about the tunnel he was digging through time. Slipping his parka back to reveal a badly burned face that was cracked and peeling, he pointed to the annual layers of ice in a core sample dug from the glacier on which we were standing. He moved his finger back in time to the ice of two decades ago. "Here's where the U. S Congress passed the Clean Air Act, ” he said. At the bottom of the world, two continents away from Washington, D. C., even a small reduction in one country's emissions had changed the amount of pollution found in the remotest end least accessible place on earth.
But the most significant change thus far in the earth' s atmosphere is the one that began with the industrial r evolution early in the last century and has picked up speed ever since. Industry meant coal, and later oil, and we began to burn lots of it – bringing rising levels of carbon dioxide (CO2) , with its ability to trap more heat in the atmosphere and slowly warm the earth. Fewer than a hundred yards from the South Pole, upwind from the ice runway where the ski plane lands and keeps its engines running to prevent the metal parts from freeze-locking together, scientists monitor the air sever al times ever y day to chart the course of that inexorable change. During my visit, I watched one scientist draw the results of that day's measurements, pushing the end of a steep line still higher on the graph. He told me how easy it is – there at the end of the earth – to see that this enormous change in the global atmosphere is still picking up speed.
Two and a half years later I slept under the midnight sun at the other end of our planet, in a small tent pitched on a twelve-toot-thick slab of ice floating in the frigid Arctic Ocean. After a hearty breakfast, my companions and I traveled by snowmobiles a few miles farther north to a rendezvous point where the ice was thinner – only three and a half feet thick – and a nuclear submarine hovered in the water below. After it crashed through the ice, took on its new passengers, and resubmerged, I talked with scientists who were trying to measure more accurately the thickness of the polar ice cap, which many believe is thinning as a re-suit of global warming. I had just negotiated an agreement between ice scientists and the U. S. Navy to secure the re-lease of previously top secret data from submarine sonar tracks, data that could help them learn what is happening to the north polar cap. Now, I wanted to see the pole it-self, and some eight hours after we met the submarine, we were crashing through that ice, surfacing, and then I was standing in an eerily beautiful snowcape, windswept and sparkling white, with the horizon defined by little hummocks, or "pressure ridges " of ice that are pushed up like tiny mountain ranges when separate sheets collide. But here too, CD, levels are rising just as rapidly, and ultimately temperature will rise with them – indeed, global warming is expected to push temperatures up much more rapidly in the polar regions than in the rest of the world. As the polar air warms, the ice her e will thin; and since the polar cap plays such a crucial role in the world's weather system, the consequences of a thinning cap could be disastrous.
Considering such scenarios is not a purely speculative exercise. Six months after I returned from the North Pole, a team of scientists reported dramatic changes in the pattern of ice distribution in the Arctic, and a second team reported a still controversialclaim (which a variety of data now suggest) that, over all, the north polar cap has thinned by 2 per cent in just the last decade. Moreover, scientists established several years ago that in many land areas north of the Arctic Circle, the spring snowmelt now comes earlier every year, and deep in the tundra below, the temperature e of the earth is steadily rising.
As it happens, some of the most disturbing images of environmental destruction can be found exactly halfway between the North and South poles – precisely at the equator in Brazil – where billowing clouds of smoke regularly black-en the sky above the immense but now threatened Amazon rain forest. Acre by acre, the rain forest is being burned to create fast pasture for fast-food beef; as I learned when I went there in early 1989, the fires are set earlier and earlier in the dry season now, with more than one Tennessee's worth of rain forest being slashed and burned each year. According to our guide, the biologist Tom Lovejoy, there are more different species of birds in each square mile of the Amazon than exist in all of North America – which means we are silencing thousands of songs we have never even heard.
But one doesn't have to travel around the world to wit-ness humankind's assault on the earth. Images that signal the distress of our global environment are now commonly seen almost anywhere. On some nights, in high northern latitudes, the sky itself offers another ghostly image that signals the loss of ecological balance now in progress. If the sky is clear after sunset -- and it you are watching from a place where pollution hasn't blotted out the night sky altogether -- you can sometimes see a strange kind of cloud high in the sky. This "noctilucent cloud" occasionally appears when the earth is first cloaked in the evening dark-ness; shimmering above us with a translucent whiteness, these clouds seem quite unnatural. And they should: noctilucent clouds have begun to appear more often because of a huge buildup of methane gas in the atmosphere. (Also called natural gas, methane is released from landfills , from coal mines and rice paddies, from billions of termites that swarm through the freshly cut forestland, from the burning of biomass and from a variety of other human activities. ) Even though noctilucent clouds were sometimes seen in the past., all this extra methane carries more water vapor into the upper atmosphere, where it condenses at much higher altitudes to form more clouds that the sun's rays still strike long after sunset has brought the beginning of night to the surface far beneath them.
What should we feel toward these ghosts in the sky? Simple wonder or the mix of emotions we feel at the zoo? Perhaps we should feel awe for our own power: just as men "ear tusks from elephants’ heads in such quantity as to threaten the beast with extinction, we are ripping matter from its place in the earth in such volume as to upset the balance between daylight and darkness. In the process, we are once again adding to the threat of global warming, be-cause methane has been one of the fastest-growing green-house gases, and is third only to carbon dioxide and water vapor in total volume, changing the chemistry of the upper atmosphere. But, without even considering that threat, shouldn't it startle us that we have now put these clouds in the evening sky which glisten with a spectral light? Or have our eyes adjusted so completely to the bright lights of civilization that we can't see these clouds for what they are – a physical manifestation of the violent collision between human civilization and the earth?
Even though it is sometimes hard to see their meaning, we have by now all witnessed surprising experiences that signal the damage from our assault on the environment --whether it's the new frequency of days when the temperature exceeds 100 degrees, the new speed with which the -un burns our skin, or the new constancy of public debate over what to do with growing mountains of waste. But our response to these signals is puzzling. Why haven't we launched a massive effort to save our environment? To come at the question another way' Why do some images startle us into immediate action and focus our attention or ways to respond effectively? And why do other images, though sometimes equally dramatic, produce instead a Kin. of paralysis, focusing our attention not on ways to respond but rather on some convenient, less painful distraction?
Still, there are so many distressing images of environ-mental destruction that sometimes it seems impossible to know how to absorb or comprehend them. Before considering the threats themselves, it may be helpful to classify them and thus begin to organize our thoughts and feelings so that we may be able to respond appropriately.
A useful system comes from the military, which frequently places a conflict in one of three different categories, according to the theater in which it takes place. There are "local" skirmishes, "regional" battles, and "strategic" conflicts. This third category is reserved for struggles that can threaten a nation's survival and must be under stood in a global context. Environmental threats can be considered in the same way. For example, most instances of water pollution, air pollution, and illegal waste dumping are essentially local in nature. Problems like acid rain, the contamination of under-ground aquifers, and large oil spills are fundamentally regional. In both of these categories, there may be so many similar instances of particular local and regional problems occurring simultaneously all over the world that the patter n appears to be global, but the problems themselves are still not truly strategic because the operation of- the global environment is not affected and the survival of civilization is not at stake.
However, a new class of environmental problems does affect the global ecological system, and these threats are fundamentally strategic. The 600 percent increase in the amount of chlorine in the atmosphere during the last forty years has taken place not just in those countries producing the chlorofluorocarbons responsible but in the air above every country, above Antarctica, above the North Pole and the Pacific Ocean – all the way from the surface of the earth to the top of the sky. The increased levels of chlorine disrupt the global process by which the earth regulates the amount of ultraviolet radiation from the sun that is allowed through the atmosphere to the surface; and it we let chlorine levels continue to increase, the radiation levels will al-so increase – to the point that all animal and plant life will face a new threat to their survival.
Global warming is also a strategic threat. The concentration of carbon dioxide and other heat-absorbing molecules has increased by almost 25 per cent since World War II, posing a worldwide threat to the earth's ability to regulate the amount of heat from the sun retained in the atmosphere. This increase in heat seriously threatens the global climate equilibrium that determines the pattern of winds, rainfall, surface temperatures, ocean currents, and sea level. These in turn determine the distribution of vegetative and animal life on land and sea and have a great effect on the location and pattern of human societies.
In other words, the entire relationship between humankind and the earth has been transformed because our civilization is suddenly capable of affecting the entire global environment, not just a particular area. All of us know that human civilization has usually had a large impact on the environment; to mention just one example, there is evidence that even in prehistoric times, vast areas were sometimes intentionally burned by people in their search for food. And in our own time we have reshaped a large part of the earth's surface with concrete in our cities and carefully tended rice paddies, pastures, wheat fields, and other croplands in the countryside. But these changes, while sometimes appearing to be pervasive , have, until recently, been relatively trivial factors in the global ecological sys-tem. Indeed, until our lifetime, it was always safe to assume that nothing we did or could do would have any lasting effect on the global environment. But it is precisely that assumption which must now be discarded so that we can think strategically about our new relationship to the environment.
Human civilization is now the dominant cause of change in the global environment. Yet we resist this truth and find it hard to imagine that our effect on the earth must now be measured by the same yardstick used to calculate the strength of the moon's pull on the oceans or the force of the wind against the mountains. And it we are now capable of changing something so basic as the relationship between the earth and the sun, surely we must acknowledge a new responsibility to use that power wisely and with appropriate restraint. So far, however, We seem oblivious of the fragility of the earth's natural systems.
This century has witnessed dramatic changes in two key factors that define the physical reality of our relation-ship to the earth: a sudden and startling surge in human population, with the addition of one China's worth of people every ten years, and a sudden acceleration of the scientific and technological revolution, which has allowed an almost unimaginable magnification of our power to affect the world around us by burning, cutting, digging, moving, and trans-forming the physical matter that makes up the earth. The surge in population is both a cause of the changed relationship and one of the clearest illustrations of how startling the change has been, especially when viewed in a historical context. From the emergence of modern humans 200 000 years ago until Julius Caesar's time, fewer than 250 million people walked on the face of the earth. When Christopher Columbus set sail for the New World 1500 years later, there were approximately 500 million people on earth. By the time Thomas Jefferson wrote the Declaration of Independence in 1776, the number had doubled again, to 1 billion. By midway through this century, at the end of World War II, the number had risen to just above 2 billion people. In other words, from the beginning of humanity's appearance on earth to 1945, it took more than ten thousand generations to reach a world population of 2 billion people. Now, in the course of one human lifetime -- mine -- the world population will increase from 2 to more than 9 million, and it is already more than halfway there.
Like the population explosion, the scientific and technological revolution began to pick up speed slowly during the eighteenth century. And this ongoing revolution has also suddenly accelerated exponentially. For example, it is now an axiom in many fields of science that more new and important discoveries have taken place in the last ten years that. in the entire previous history of science. While no single discover y has had the kind of effect on our relationship to the earth that unclear weapons have had on our relationship to warfare, it is nevertheless true that taken together, they have completely transformed our cumulative ability to exploit the earth for sustenance -- making the consequences, of unrestrained exploitation every bit as unthinkable as the consequences of unrestrained nuclear war.
Now that our relationship to the earth has changed so utterly, we have to see that change and understand its implications. Our challenge is to recognize that the startling images of environmental destruction now occurring all over the world have much more in common than their ability to shock and awaken us. They are symptoms of an underlying problem broader in scope and more serious than any we have ever faced. Global warming, ozone depletion, the loss of living species, deforestation -- they all have a common cause: the new relationship between human civilization and the earth's natural balance. There are actually two aspects to this challenge. The first is to realize that our power to harm the earth can in-deed have global and even permanent effects. The second is to realize that the only way to understand our new role as a co-architect of nature is to see ourselves as part of a complex system that does not operate according to the same simple rules of cause and effect we are used to. The problem is not our effect on the environment so much as our relationship with the environment. As a result, any solution to the problem will require a careful assessment of that relationship as well as the complex interrelationship among factors within civilization and between them and the major natural components of the earth's ecological system.
There is only one precedent for this kind of challenge to our thinking, and again it is military. The invention of nuclear weapons and the subsequent development by the Unit-ed States and the Soviet Union of many thousands of strategic nuclear weapons forced a slow and painful recognition that the new power thus acquired forever changed not only the relationship between the two superpowers but also the relationship of humankind to the institution at war-fare itself. The consequences of all-out war between nations armed with nuclear weapons suddenly included the possibility of the destruction of both nations – completely and simultaneously. That sobering realization led to a careful reassessment of every aspect of our mutual relationship to the prospect of such a war. As early as 1946 one strategist concluded that strategic bombing with missiles "may well tear away the veil of illusion that has so long obscured the reality of the change in warfare – from a fight to a process of destruction.”
Nevertheless, during the earlier stages of the nuclear arms race, each of the superpower s assumed that its actions would have a simple and direct effect on the thinking of the other. For decades, each new advance in weaponry was deployed by one side for the purpose of inspiring fear in the other. But each such deployment led to an effort by the other to leapfrog the first one with a more advanced deployment of its own. Slowly, it has become apparent that the problem of the nuclear arms r ace is not primarily caused by technology. It is complicated by technology, true; but it arises out of the relationship between the superpowers and is based on an obsolete understanding of what war is all about.
The eventual solution to the arms race will be found, not in a new deployment by one side or the other of some ultimate weapon or in a decision by either side to disarm unilaterally , but ratter in new understandings and in a mutual transformation of the relationship itself. This transformation will involve changes in the technology of weaponry and the denial of nuclear technology to rogue states. But the key changes will be in the way we think about the institution of war far e and about the relationship between states.
The strategic nature of the threat now posed by human civilization to the global environment and the strategic nature of the threat to human civilization now posed by changes in the global environment present us with a similar set of challenges and false hopes. Some argue that a new ultimate technology, whether nuclear power or genetic engineering, will solve the problem. Others hold that only a drastic reduction of our reliance on technology can improve the conditions of life -- a simplistic notion at best. But the real solution will be found in reinventing and finally healing the relationship between civilization and the earth. This can only be accomplished by undertaking a careful reassessment of all the factors that led to the relatively recent dramatic change in the relationship. The transformation of the way we relate to the earth will of course involve new technologies, but the key changes will involve new ways of thinking about the relationship itself.
第三课
沙漠之舟
艾尔o戈尔
我头顶烈日站在一艘渔船的滚烫的钢甲板上。这艘渔船在丰收季节一天所处理加工的鱼可达15吨。但现在可不是丰收季节。这艘渔船此时此刻停泊的地方虽说曾是整个中亚地区最大的渔业基地，但当我站在船头向远处眺望时，却看出渔业丰收的希望非常渺茫。极目四顾，原先那种湛蓝色海涛轻拍船舷的景象已不复存在，取而代之的是茫茫的一片干燥灼热的沙漠。渔船队的其他渔船也都搁浅在沙漠上，散见于陂陀起伏、绵延至天边的沙丘间。十年前，咸海还是世界上第四大内陆湖泊，可与北美大湖区五大湖中的最大湖泊相媲美。而今，由于兴建了一项考虑欠周的水利工程，原来注入此湖的水被引入沙漠灌溉棉田，咸海这座大湖的水面已渐渐变小，新形成的湖岸距离这些渔船永远停泊的位置差不多有40公里远。与此同时，这儿附近的莫里那克镇上人们仍在生产鱼罐头，但所用的鱼已不是咸海所产，而是从一千多英里以外的太平洋渔业基地穿越西伯利亚运到这儿来的。
我因要对造成环境危机的原因进行调查而得以周游世界，考察和研究许多类似这样破坏生态环境的事例。一九八八年深秋时节，我来到地球的最南端。高耸的南极山脉中太阳在午夜穿过天空中的一个孔洞照射着地面，我站在令人难以置信的寒冷中，与一位科学家进行着一场谈话，内容是他正在挖掘的时间隧道。这位科学家一撩开他的派克皮大衣，我便注意到他脸上因烈日的曝晒而皮肤皲裂，干裂的皮屑正一层层地剥落。他一边讲话一边指给我看。从我们脚下的冰川中挖出的一块岩心标本上的年层。他将手指．到二十年前的冰层上，告诉我说，"这儿就是美国国会审议通过化空气法案的地方。"这里虽处地球之顶端，距美国首都华盛顿两大洲之遥，但世界上任何一个国家只要将废气排放量减少一席在空气污染程度上引起的相应变化便能在南极这个地球上最偏而人迹难至的地方反映出来。
迄今为止，地球大气层最重要的变化始于上世纪初的工业命，变化速度自那以后逐渐加快。工业意味着先是煤、后是石油消耗。我们燃烧了大量的煤和石油--导致大气层二氧化碳含的增加，这就使更多的热量得以留存在大气层中，从而使地球的候逐渐变暖。离南极极点不到一百码远，在雪上飞机降落的冰铺道上风处，科学家们一日数次地测量大气，以便绘制图表记录下无情的变化。雪上飞机在冰铺跑道上降落后，引擎仍得保持运聋以防金属部件冻住而无法发动。在我访问期间，我观看了一位科家绘出那天的测量结果，把图表上一条斜度很大的上升的线再上推进。他告诉我--在这地球的尽头--很容易看清全球大层的巨大变化的速度仍在加快。
两年半以后，在地球的另一端，在寒冷至极的北冰洋上漂浮的一块十二英尺厚的冰板上搭起的小帐篷里我又体验到了在午的阳光下睡觉的滋味。饱吃了一顿早餐后，我和同伴们一起乘雪防滑汽车北行数英里，到了约定会合地点，那儿的冰层较薄--有三英尺半厚--水下有一艘核潜艇在那儿徘徊着。潜艇破冰上来，载上新的乘客后又潜了下去。我也就开始同那些正设法以高的精确度测量极地冰帽厚度的科学家们进行交谈。许多人认北极冰层由于地球气候的转暖而正在变薄。此前我刚刚通过谈使美国海军方面与研究北极冰层的科学家达成协议，向他们提由水下声纳系统探测得到的本来属于最高机密的有关资料，这资料有助于他们了解北极冰层所发生的情况。现在我想实地考一下北极极点。我们登上潜艇约八个小时后，潜艇冲破冰层浮上面。于是，我便置身于一片神奇瑰丽的冰雪世界中。雪原上寒风劲扫，银光闪耀，其边缘则是一道由连绵起伏的小冰丘或由冰席相撞、相互挤压而形成小型山脉的冰层"压脊"勾勒出的地平线。但即使在这儿，空气中二氧化碳的含量也在不断上升，最后气温也必然会随之上升--事实上，地球气候变暖会使南北极地区在气温上升的速度上远高于世界的其他地区。随着极地气温的升高，这里的冰层会融化变薄。由于南北极的冰帽对全球的气候有着至关重要的调节作用，它们的融化将会带来灾难性的后果。
探索这些问题并不是一种纯理论性的工作。我从北极回来后过了六个月，就有一队科学家报称北极冰层的分布结构已发生显著变化；另一队科学家则在考察报告中提出了一个更有争议的说法(如今已有大量资料可以佐证)：总体说来，仅在过去十年当中，北极冰层已融化了百分之二。另外，科学家们还在几年前就已证实，在北极圈以北的许多地区，春季雪融的时间逐年提前，而且冻土带的地下深处的温度都在稳步上升。
凑巧的是，破坏生态环境的一些最典型的、最令人担忧的事例刚好都发生在南北极正中间的地方--巴西境内的赤道带上--那儿滚滚浓烟时常弥漫着辽阔但现又面临着破坏的亚马孙热带雨林的上空。亚马孙雨林正被人们大片大片地烧毁，以便腾出空地作饲养速食肉牛的牧场。我1989年初去那儿时得知，现在旱季时节放火焚烧森林的时间正逐年提前，其结果是每年都有面积比整个田纳西州还大的大片森林遭到砍伐焚烧。据给我们当向导的生物学家汤姆o洛夫乔伊介绍，亚马孙雨林中每平方英里的林区栖息的禽鸟种类多于整个北美洲现存的禽鸟种类--这就意味着我们正在使成千上万种我们从来没有听到过的飞禽的歌声永远消失。
人们也不一定非要周游世界才能目睹人类对地球的破坏。今天的世界上，预示着地球生态危机的景象已是随处可见。在北方高纬度地区，夜晚的天空有时也会呈现出另一种预示地球上日趋严重的生态失衡的阴森景象。假如日落后天空明朗无云--而且你又置身于一个空气污染还没有严重到足以完全遮蔽夜空的地方进行观察的话--你会看见天空高处有时会出现一种奇异的云团。这种"夜光云团"偶尔出现于夜幕开始笼罩大地的时候，它呈半透明的白色，在高空中闪烁发光，看起来颇不像自然之物。其实，这种云团也确非自然之物：近年来由于大气中甲烷含量的大幅度增高，夜光云团的出现频率也随着上升了。(甲烷又称天然气，它产生于填土、煤矿、糠壳、新砍伐的林地里群聚的白蚁、燃烧生物以及人类许多其他的活动过程中。)虽说过去天空偶尔也出现过夜光云团，但大气层中所含的那些过量的甲烷会将更多的水蒸气带到高层大气中；水蒸气在更高处凝结，会形成更厚的云层，夜幕降临以后很久，这些位于高空的云层下方还在受着太阳光的照射。
对天空中出现的这些奇异现象我们应当如何看待呢?是仅仅叹为奇观还是怀着像我们在动物园中观看动物时感受到的那种复杂的感情?也许我们应当为自己所具有的破坏力而惊奇赞叹：正如人类由于大量猎取象牙致使大象面临灭种威胁一样，我们今天正由于大量糟蹋和破坏地球上的自然资源而使白天和黑夜之间的平衡遭到破坏。我们的这种行为更进一步地增加了地球变暖的危险，因为甲烷是一种形成速度极快韵温室效应气体，它在大气中的总含量仅次于二氧化碳和水蒸气，使高空大气层的化学成分都发生了变化。即使不去考虑这种危险，但只要意识到我们让这些闪烁着阴森森的鬼火般光亮的云团笼罩着自己头顶上的夜空，这还不就足以令我们警醒吗?难道说是我们的眼睛因为过分习惯于人类文明之光而对这些云团视而不见--看不出它们乃是人类文明同地球之间的激烈冲突的一种具体表现形式吗?
尽管有时很难理解其真正含义，我们大家都曾耳闻目睹过一些反映人类对生态环境造成破坏的惊人的现象--或是气温超过一百度的高温天气出现频率的增加，或是太阳灼伤人的皮肤的速度的加快，或是公众对越积越多的废物该如何处理这一问题进行讨论的热情的高涨。但是，我们大家对这些现象所作的反应却很有点奇怪。我们为何不采取切实有效的行动来保护生态环境呢?这个问题也可以换一种方式来问：为什么有些现象会引起我们重视，促使我们立即采取行动，努力寻求有效对策?为什么另外一些现象，虽然有时也同样严重，却让人们无动于衷，人们的注意力不是集中在寻求积极有效的对策而是某种方便省事的规避策略呢?
话说回来，由于令人担忧的生态环境受到破坏的现象太多了，使人有时确乎难以认识其实质意义和影响。在对这些威胁生态环境的现象进行考察分析之前，下面的做法也许是有益的：对这些现象进行分级归类，从而使我们的思想感情条理化，以便根据实际情况采取相应的合理的对策。
有一套行之有效的分级归类方法源自于军队。他们经常将冲突根据其发生范围的大小分为三级，即"局部性冲突"，"地区性战斗"，及"战略性对抗"。第三级指的是直接威胁到一个国家的生存，因而必须以全球局势为背景来进行认识的军事对抗行为。
对生态环境方面的危机也可以这样来加以考虑。比如，水域的污染、空气的污染和非法倾倒垃圾的行为多半属于局部性的问题，而诸如酸雨、地下含水层的污染以及大面积的石油泄漏一类的问题则基本上是地区性的。这两类问题都带有普遍性，世界各地可能同时出现性质相同的局部性问题和地区性问题，因此，这些局部性问题和地区性问题又似乎可以看作是全球性的问题。但它们并不属于战略性问题，因为这些问题并没有对全球生态环境的本质结构造成影响，也没有直接威胁到人类社会的生存。
然而，新的一类环境问题确实影响全球生态系统，而这些威胁基本上是战略性的。过去四十年中大气层氯的含量增加了百分之六百，这不仅发生在那些生产与此直接相关的氟里昂的国家，而且发生在所有国家的上空，还同样发生在南极上空、北极上空和太平洋上空--从地球表面一直到天空深处。氯含量的增加破坏了地球调节太阳通过大气层射到地面的紫外线辐射量的全球程序。如果我们让氯含量继续增加，那么紫外线辐射量也将增加--终有一天会威胁到所有的动植物的生存。
地球气候转暖也是一种战略性威胁。自第二次世界大战以来，大气层中二氧化碳和其他一些吸热物质分子的含量已增加了近百分之二十五，这便对地球自身具有的调节太阳热量在大气层中存留量的能力构成了世界性的威胁。由此导致的大气层中热量的增高会严重破坏地球的气候平衡机制，从而影响到地球上的风量、雨量、地面温度、洋流和海面高度，而正是这些因素反过来又决定着陆地和海上动植物的生态分布，也在很大程度上决定着人类社会的定居地点和生活方式。
换句话说，由于人类社会已突然具备了改变整个地球而不只是某一特定地区的生态环境的能力，人类与地球之间的关系便整个地发生了改变。众所周知，人类文明对地球上的环境一贯有着极大的影响。且举一例来说明吧：还在远古时代，人类为了觅食求生，有时便纵火焚毁大片原始森林，这是有据可考的。而在今天我们这个时代，人类已经把地球表面的很大一部分完全改换了面貌，城镇里的地面换成了混凝土，乡村里的地面则改造成了精心培育的稻田、牧场、麦田和其他农作物种植地。人类加于地球上的这类改变，有时虽然似乎有着深远的影响，但它们对全球生态系统直到最近仍只产生着微不足道的影响。在我们这个时代以前，的确可以高枕无忧地认为，无论是人类所曾做过的或是所能做的任何事情，都不可能对地球上的环境产生永久性的影响。但是今天，我们却必须抛弃这种想当然的想法，这样才能够以战略性眼光来考虑并重新认识我们人类同地球环境之间的关系。
今天，人类文明已成了地球生态环境变化的主要原因。然而，我们却拒不承认这一事实，并且觉得很难想象，人类对地球的影响，现在也得用测量月球对海水的吸引力或暴风对高山的侵蚀作用的方法来测量。假如我们现在已有能力改变像太阳与地球之间的关系这样重要事物的话，我们自然应该承认自己有责任谨慎而有节制地使用这种权力。但迄今为止，我们似乎对地球上十分脆弱的生态系统漠然置之。
本世纪中有两个决定人类与地球之间的本质关系的关键因素发生了重大变化：一是人口的急剧增长，二是科学技术的突飞猛进。世界人口每十年的增长数字就相当于全中国的人口总数，而科技的发展使我们具有了几乎是不可思议的力量，可以对构成这个地球的物质恣意地进行焚烧、砍伐、挖掘、搬运和改造。
人口的增长既是人类与地球之间的关系发生变化的一个原因，同时也是向人们昭示这一变化有多么巨大的一个显著标志，在我们从历史的角度来看待这一问题的时候尤其如此。自二十万年前现代人类开始出现时起直到朱利叶斯o凯撒的时代，在地球上生活过的人类总计不足二亿五千万。一千五百年后，当克里斯托弗o哥伦布扬帆渡海去寻找新大陆时，地球上的人口大约是五亿。到托马斯o杰佛逊起草《独立宣言》的一七七六年，地球上的人口便又翻了一番，达到十亿。到本世纪中叶，第二次世界大战结束之时，地球上的人口总数刚过二十亿。
换句话说，自人类最初出现时起到一九四五年，经历了一万多代人的时间才使世界人口达到二十亿。而如今，在一个人--我--的一生的时间里，世界人口便能从二十亿增长到九十亿。目前，这个增长过程业已完成一大半。
像人口增长的情形一样，科学技术的发展在十八世纪慢慢开始加速，而现在的发展速度则以代数指数的速度递增。举例来说，在科学的许多领域中现在都有这样一个公认的说法：最近十年中产生的重大科学新发现超过以往科学史上的新发现的总和。尽管任何一项新发现对人类与地球之间的关系所造成的影响都无法同核武器对人类与战争的关系所造成的影响相比，但这些科学发现结合在一起，却是千真万确地使人类所积累的开发利用地球资源以求生存的能力发生了根本性的变化--在这样的条件下，如果人类不加节制地随意开发利用地球资源，其后果就会同随意发动核战争一样不堪设想。
既然人类与地球之间的关系发生了这样根本性的变化，我们就有必要考察分析这一变化并认清其实质意义。我们首先需要认识的是，目前正在世界各地不断发生的破坏生态环境的各种令人怵目惊心的事例，除了对我们产生震撼和警醒作用外，它们之间还有许多共同的特点。它们标志着一个在影响范围和严重性方面都是人类前所未遇的大问题的存在。地球气候的转暖、臭氧层的破坏、物种的消亡、森林的毁坏--这些现象有一个共同的原因：人类文明与地球生态平衡的关系的变化。
我们的认识任务包含两个方面：一是要认识到人类对地球进行破坏的能力具有全球性的、甚至是永久性的影响；二是要认识到，理解人类作为大自然的创造者之一的新角色的唯一方法，是将自己视为一套不按我们所熟悉的因果定律运作的复杂体系的一个组成部分。我们所要解决的不是人类对环境如何产生影响的问题，而是人类如何处理同环境关系的问题。因此，要寻求解决问题的办法，就必须仔细研究、认真评估这种关系的重要性，也要认真分析评估人类文明中各种要素之间以及这些要素与地球生态系统的各个主要组成部分之间的相互关系的重要性。
对我们的思维方式提出这种挑战性要求的先例只有一个，而这一先例又是来自军事方面的。核武器的发明及其后美国和苏联研制出成千上万的战略性核武器这一现实，迫使人们痛苦地、逐渐地认识到，由发展核武器而获取的新能量不仅永远改变了两个超级大国之间的关系而且也永远地改变了人类与战争惯例之间的关系。拥有核武器的国家之间如果爆发全面大战，其结果可能是双方同时而彻底的毁灭。这一认识使人们头脑清醒起来，开始认真地对这样一种战争的前景下双方关系的各个方面重新进行认识。早在一九四六年就有一位军事战略家下过断言，认为使用核弹进行的战略轰炸"完全有可能撕开长期掩盖着战争性质变化的那一层薄纱，现实是战争已由拼斗厮杀发展成为彻底的毁灭"。
然而，在核军备竞赛的初期，两个超级大国都一厢情愿地认为他们扩充军备的行动会对对方的思维产生完全直接的影响。几十年来，双方在研制新武器方面的每一点进展都是为了用来威胁对方，但每次这样做的结果却只是促使对方加倍努力地研制配备更先进的武器。慢慢地，人们终于看清了：造成核军备竞赛问题的主要因素并不是科技。核军备竞赛问题因科学技术的发展而变得复杂了，这倒没错，但其起因却在于两个超级大国之间互相对峙的关系，而其根源则在于人们对战争究竟意味着什么这一问题的陈旧的认识。
解决军备竞赛问题的最终办法也许能够找到，但不能从竞赛双方中任何一方研制出某种终极武器的行动中去寻找，也不能从任何一方单方面裁军的决定中去寻找，而只能从双方重新认识并调整彼此间的关系的行动中去寻找。要完成这种关系的调整，必须使武器制造技术发生变化，并对凶悍好斗国家封锁核技术，但更为重要的还是要使我们自己对于战争和国与国之间的关系等问题发生思想认识上的变化。
当前人类文明对全球环境的威胁的战略实质以及全球环境的变化对人类文明的威胁的战略实质向我们提出了一系列相似的挑战，同时也使我们产生了一些自欺欺人的期望。有的人认为，有了某种崭新的终极技术--不管是核能还是基因工程--就可以解决这个问题。还有的人则认为，只有大大减少我们对技术的依赖才能改善人类的生存环境--这种看法充其量是一种简单化的看法。真正的解决办法要从重新设计以及最终弥合文明与地球间的关系中去寻找。要完成这一点，只有通过重新仔细估量导致这种关系在较近时期内发生的剧烈变化的所有各种因素才行。改变我们与地球的关系的途径当然会涉及到新技术的发明和应用，但关键的变化将与对这种关系本身的新的思路有关。
词汇(Vocabulary)
lap ( v．) :(of waves，etc．)move or strike gently with a light，splashing sound such as a dog makes in lapping(波浪)拍打；泼溅
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divert ( v．) :turn(a person or thing)aside(from a course，direction，etc．)；deflect转移；使(人或物)转向；岔开，使偏斜
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Antarctic ( adj. ) :of or near the South Pole or the region around it南极的；近南极的；南极区的；南极地带的；南极周围的
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Trans-Antarctic (adj.) : crossing or spanning the Antarctic横贯南极的；横贯南极地带的
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parka ( n.) :a hip-length pullover fur garment with a hood，worn 1n arctic regions风雪大衣，派克大衣
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glacier ( n.) :a slowly moving river or mass of ice and snow that forms in areas where the rate of snowfall constantly exceeds the rate at which the snow melts冰河；冰川
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accessible ( adj.) : that can be approached or entered；easy to approach or enter能够接近的；能够进去的；易接近的；易进去的
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trap ( v．) :catch in or as in a trap；entrap诱捕；计捉
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inexorable ( adj.) :that cannot be altered，checked，etc．不可变的；不可抗拒的；无情的
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graph ( n.) :a diagram consisting of nodes and links and representing logical relationships or sequences of events(曲线)图，标绘图；图表；图形
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slab ( n.) :a piece that is flat，broad，and fairly thick平板；厚片
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frigid ( adj.) :extremely cold；without heat or warmth极冷的，寒冷的，严寒的
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snowmobile ( n.) :any of various motor vehicles for traveling over snow，usually with steerable runners at the front and tractor treads at the rear(机动)雪车；(履带式)雪上汽车
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rendezvous ( n.) :[Fr．]a place designated for meeting or assembling[法语]指定集合地；会合点
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hover ( v．) :stay suspended or flutter in the air near oneplace盘旋
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eerie，eery ( adj. ) :mysterious，uncanny，or weird，esp. in such a way as to frighten or make uneasy神秘的，离奇的，怪异的；阴森的，恐怖的，可怕的／eerily adv．
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hummock ( n.) :ridge or rise in an ice field冰群；(冰原上的)冰丘
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collide ( v．) :come into violent contact；strike violently against each other；crash碰撞；猛撞；互撞
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scenario ( n.) :a sequence 0f events esp. when imagined；an account or synopsis of a projected course of action or events(设想中的)未来事态；方案
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controversial ( adj. ) :of，subject to，or stirring up controversy；disbatable争论的；引起争论的；
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tundra ( n.) :any of the vast，nearly level，treeless plains of the arctic regions冻原；苔原；冻土带
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equator ( n.) :an imaginary circle around the earth，equally distant at all points from both the North Pole and the South Pole，dividing the earth's surface into the Northern Hemisphere and the Southern Hemisphere赤道
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billow ( v．) :surge，swell，or rise like or in a billow(巨浪)奔腾；(波涛)汹
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pasture ( n.) :
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( n.) :．ground suitable for grazing牧场
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slash (v．) :cut or wound with a sweeping stroke or strokes，as of a knife(用刀等)猛砍，乱砍
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blot (v．) :make blots on；spot；stain；blur(esp. used in blot out：darken or hide entirely；obscure)涂污；玷污；把……弄模糊；遮暗(尤用于bolt out：把……弄模糊；遮暗，遮蔽；掩蔽)
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noctilucent (adj.) :designating or of a luminous cloud of unknown composition。visible at night in the polar regions at an altitude of c．50 miles夜光云的；夜间发光的
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shimmer ( v．) :shine with an unsteady light；glimmer闪烁；发出微光
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translucent ( adj.) :1etting light pass but diffusing it so that objects on the other side cannot be clearly distinguished；partially transparent，as frosted glass半透明的
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buildup ( n.) :a gradual increase in amount，power，influence，etc．；expansion(在数目、力量、影响等方面)逐渐增加，扩大，扩充；集结
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methane ( n.) :a colorless，odorless，inflammable gaseous hydrocarbon，CH4，present in natural gas and formed by the decomposition of vegetable matter，as in marshes and mines. or produced artificially by heating carbon monoxide and hydrogen over a nickle catalyst甲烷；沼气
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landfill ( n.) :the disposal of garbage or rubbish by burying it under a shallow layer of ground埋入地下的垃圾
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paddy ( n.) :rice in the husk，growing or gathered稻，谷
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termite ( n.) :a kind of insect found chiefly in tropical areas，very destructive to wood，textiles，etc．，which makes large hills of hard earth白蚁
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biomass ( n.) :the total mass or amount of living organisms in a particular area or volume生物量
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extinction ( n.) :the fact or state of being or becoming extinct；dying out，as of a race，species of animal，etc．(动物的)灭绝，绝种
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rip (v．) :cut or tear apart roughly or vigorously撕，扯
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spectral ( adj.) : of or like a specter；phantom；ghostly鬼怪(似)的；幽灵(般)的
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skirmish ( n.) :a brief fight or encounter between small groups，usually an incident of a battle小规模战斗；前哨战
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aquifer ( n.) :an underground layer of porous rock，sand，etc．containing water，into which wells can be sunk含水层(能对水井提供重要经济价值的水量的地下岩层)
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chlorine ( n.) :a greenish-yellow，poisonous，gaseous chemical element with a disagreeable odor．used as a bleaching agent，in water purification，in various industrial processes，etc．(symbol C1)氯(符号C1)
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chlorofluorocarbon ( n.) :any of a series of gaseous or low-boiling，inert，nonflammable derivatives of methane or ethane，used as refrigerants and solvents，and as propellants in aerosol products[化]氟利昂
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disrupt ( v．) :disturb or interrupt the orderly course of扰乱；破坏
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ultraviolet ( adj. ) :1ying just beyond the violet end of the visible spectrum and having wavelengths shorter than approximately 4 000 angstroms紫外(线)的
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molecule ( n.) :the smallest particle of an element or compound that can exist in the free state and still retain the characteristics of the element or compound[化]分子
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equilibrium ( n.) :a state of balance or equality between opposing forces平衡(状态)；平均；相称
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exponential ( adj.)[Math．] :of or relating to an exponent：involving a variable or unknown quantity as an exponent[数]指数的；幂的
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axiom ( n.) :a statement universally accepted as true；maxim格言，箴言
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cumulative (adj. ) :increasing in effect，size, quantity，etc．by successive additions；accumulated累积的，堆积的；累加的；(作用、大小、数量等)渐增的
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sustenance ( n.) :one's means of livelihood；maintenance；support生计；支撑；支持，维持
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ozone ( n.) :n unstable，pale-blue gas，O3，with a penetraring odor(an allotropic form of oxygen，formed usually by a silent electrical discharge in air，and used as an oxidizing，deodorizing．and bleaching agent and in the purification of water)[化]臭氧
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depletion ( n.) :the gradual using up or destruction or capital assets，esp. of natural resources资产(尤指自然资源)的折耗，耗减
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deforestation ( n.) :the act or action of clearing (1and)of forests of trees毁林，滥伐森林
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precedent ( n.) :existing practice resulting from earlier precedents先例；前例
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sober ( v．) :make or become self-controlled，calm，serious in thought，etc．(使)变清醒(或冷静、严肃、庄严等)
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weaponry ( n.) :the design and production o{weapons武器设计和生产
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deploy ( v．) :spread out or place in accordance with a plan展开；部署
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leapfrog ( v．) :jump or skip over跃过；越过
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obsolete ( adj.) :no longer in use or practice；discarded；no longer in fashion；out-of-date已废弃的；已不用的；过时的；老式的
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simplistic (adj.) :making complex problems unrealistically simple；oversimplifying or oversimplified过分简单化的
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短语 (Expressions)
at stake: to be won or lost；being risked 在胜败关头，冒风险
例： This decision put out lives at stake．这一决定，我们的生命就凶吉难保了。 |