Unit 8 Focus on Global Warming课文翻译综合教程二

Unit 8 Focus on Global Warming

John Weier

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. As an Internet search on global warming now attests, the subject

has become as rooted in our public consciousness as Madonna

2

or microwave cooking.

1

Perhaps all this attention is deserved. With the possible exception of another world

war,

giant

asteroid,

or

an

incurable

plague,

global

warming

may

be

the

single

largest

threat to our planet.

2

For decades human factories and cars have spewed 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

harbinger

of

what

is

to

come.

3

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.

Our Warming Planet

What

has

worried

many

people

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.

Nitrogen-based

fertilizers,

which

we

use

on

nearly

all

our

crops,

release

unnatural

amounts of nitrogen oxide 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)

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.

Many

scientists

fear

that

the

increased

concentrations

of

greenhouse

gases

have

prevented

additional

thermal

radiation

from

leaving

the

Eart

h.

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.

4

Much

of

the

available

climate

data

appear

to

back

these

fears.

5

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.

6

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

Siberia

—

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 against changes in climate.

7

A slight

increase

in

heat

and

rain

in

equatorial

regions

would

likely

spark

an

increase

in

vector-borne

diseases

such

as

malaria.

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

Maldives. All across the globe, hotter summers could lead to more cases of heatstroke 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

actions

to

slow

down

global

warming.

8

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

oxides,

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 mitigate the impacts of global warming and adapt to those

most likely to occur,

9

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