Focus onGlobal Warming
为什么地球越来越热
Twenty-five years ago if you made a trip to the
local library and perused the periodical section for articles on global
warming, you'd probably have come up with only a few abstracts from
hardcore science journals or maybe a blurb in some esoteric geopolitical
magazine.1 As an Internet search on global
warming now attests2, the subject has become
as rooted in our public consciousness as Madonna or microwave cooking.
Perhaps all this attention is deserved. With the possible exception
of another world war, a giant asteroid, or an incurable plague, global
warming may be the single largest threat to our planet.3
For decades human factories and cars have spewed4
billions of tons of greenhouse gases into the atmosphere, and the climate
has begun to show some signs of warming. Many see this as a harbinger5
of what is to come. If we don't curb our greenhouse gas emissions, then
low-lying nations could be awash in seawater, rain and drought patterns
across the world could change, hurricanes could become more frequent,
and El Ninos could become more intense.6
Our Warming Planet
What has many people worried now is that over the past 250 years humans
have been artificially raising the concentration of greenhouse gases
in the atmosphere. Our factories, power plants, and cars burn coal and
gasoline and spit out a seemingly endless stream of carbon dioxide.
We produce millions of pounds of methane by allowing our trash to decompose
in landfills and by breeding large herds of methane-belching cattle.7
Nitrogen-based fertilizers, which we use on nearly all our crops, release
unnatural amounts of nitrogen oxide8 into the
atmosphere.
Once these carbon-based greenhouse gases get into the atmosphere,
they stay there for decades or longer. According to the Intergovernmental
Panel on Climate Change (IPCC)9, since the
industrial revolution, carbon dioxide levels have increased 31 percent
and methane levels have increased 151 percent. Paleoclimate readings
taken from fossil records show that these gases, two of the most abundant
greenhouse gases, are at their highest levels in the past 420,000 years.10
Many scientists fear that the increased concentrations of greenhouse
gases have prevented additional thermal radiation from leaving the Earth.
In essence, these gases are trapping excess heat in the Earth's atmosphere
in much the same way that a windshield traps solar energy that enters
a car.11
Much of the available climate data appear to back these fears. Temperature
data gathered from many different sources all across the globe show
that the surface temperature of the Earth, which includes the lower
atmosphere and the surface of the ocean, has risen dramatically over
several decades. Worldwide measurements of sea level show a rise of
0.1 to 0.2 meters over the last century. That's an increase of roughly
1℃ every 4,000 years. Readings gathered from glaciers reveal a steady
recession of the world's continental glaciers. Taken together, all of
these data suggest that over the last century the planet has experienced
the largest increase in surface temperature in 1,000 years.
Not surprisingly, many scientists speculate that such changes in the
climate will probably result in hotter days and fewer cool days. According
to the IPCC, land surface areas will increase in temperature over the
summer months much more than the ocean. The mid-latitude to high-latitude
regions in the Northern Hemisphere- areas such as the Continental United
States, Canada, and Siberia12 - will likely
warm the most. These regions could exceed mean global warming by as
much as 40 percent.
As far as human health is concerned, those hit hardest will probably
be residents of poorer countries that do not have the funds to fend
against13 changes in climate. A slight increase
in heat and rain in equatorial regions would likely spark an increase
in vector-borne diseases such as malaria.14
More intense rains and hurricanes could cause more severe flooding and
more deaths in coastal regions and along riverbeds. Even a moderate
rise in sea level could threaten the coastlines of low-lying islands
such as the Maldives15. All across the globe,
hotter summers could lead to more cases of heat stroke and deaths among
those who are vulnerable, such as older people with heart problems.
The warmer temperatures may also lead to higher levels of near-surface
ozone from cars and factories, which would likely cause more perilous
air quality days and hospital admissions for those with respiratory
problems.
Taking actions
Fortunately, we can take action to slow global warming. Global warming
results primarily from human activities that release heat-trapping gases
and particles into the air. The most important causes include the burning
of fossil fuels such as coal, gas, and oil, and deforestation. To reduce
the emission of heat-trapping gases like carbon dioxide, methane, and
nitrous oxides16, we can curb our consumption
of fossil fuels, use technologies that reduce the amount of emissions
wherever possible, and protect the forests in the world.
We can also do things to mitigate17 the impacts
of global warming and adapt to those most likely to occur, e.g., through
careful planning and other strategies that reduce our vulnerability
to global warming.
But we can't stop there. We are also advocating policies that will
combat global warming over the long term. Things like clean cars that
run on alternative fuels, environmentally responsible renewable energy
technologies, and stopping the clear-cutting18
of valuable forests.
Clearly, global warming is a huge problem. It will take everyone ?governments,
industry, communities and individuals working together to make a real
difference. Fortunately you can be part of them.
1. 25 年前如果你去当地的图书馆期刊室里寻找全球气候变暖的文章，大概只能从主要科学杂志里找到一些抽象的概念或者在艰涩难懂的地理政治学杂志中得到一段简介。hardcore：（组织或运动成员中）中坚的，骨干的；esoteric/;es2u#terik/：难理解的，只有内行才懂的；blurb：
印在书籍等护封上的简介，吹捧性短文。
2. attest：
证明……是真的，表明。
3. 除了爆发另一次世界大战、一颗巨型小行星撞击地球、或无法治愈的瘟疫，全球变暖可能就是地球面临的惟一的最大威胁。
asteriod/#*st2r0id/：［天］小行星。
4. spew：放出，发出。与下一段的spit
out意思相同。
5. harbinger/#ha:bind32(r)/：前兆，预示。
6. 倘若我们不控制温室气体的排放量，地势低的国家可能被海水淹没，全球的降水和干旱情况也会改变，飓风将变得更加频繁，而厄尔尼诺现象也会更加明显。
greenhouse：［气］温室效应，指地球大气吸收太阳热的一种效应，大气起着如温室一样的作用；
El Nino/el#ni:nj2u/："厄尔尼诺"，是西班牙语"圣婴"的意思，指在赤道太平洋东部和中部的海水出现大范围异常偏暖现象，每次持续６个月以上，它将会对大气产生不可估量的作用，从而导致气候的异常变化。
7. 我们任由垃圾在埋填地分解并饲养大批排出甲烷的牛群，从而制造出数百万磅的甲烷。methane/#me8ein/：［化］甲烷，沼气；landfill：（用土覆盖垃圾、废物等的）废弃物埋填地。
8. nitrogen oxide/#naitr2d32n
#0ksaid/：一氧化氮。
9. IPCC：政府间气候变化专业委员会，由全球气候组织和联合国环境署于1988年共同建立，主要活动是收集影响全球气候的经济、社会和其他各方面的数据和资料，但不作研究。
10. 据化石记载的地质气候指标，空气中两种含量最高的温室气体已经达到了过去42万年以来的最高点。paleoclimate/#p*li2u;klaimit/：［地］古气候、地质气候；reading：（标度盘、仪表上的）读数、指示数。
11. 本质上来说，这些气体捕捉地球大气层里的过多热量使之无法散逸，这与汽车的风挡留住进入车内的太阳能类似。windshield：相当于windscreen，汽车前部的挡风玻璃。
12. Siberia：西伯利亚。
13. fend against：阻挡，击退，此处意思是"对付"。
14. 赤道地区气温与降水稍有增加就可能引发疟疾等媒介传染性疾病的增多。spark：点燃，触发；vector-borne：传病媒介传染的。
15. Maldives：马尔代夫（群岛）[亚洲岛国]，位于斯里兰卡西南的印度洋上，由19组珊瑚环礁组成。
16. nitrous oxide：一氧化二氮。
17. mitigate：使缓和，使减轻。
18. clear-cutting：［农］皆伐，指将一块林区的树木全部砍去。
