National Geographic - USA (2020-04)

ALASKA WILD-
LANDS PROTECTED
The Alaska National Interest
Lands Conservation Act sets
aside more than 100 million
acres of wilderness in national
parks, preserves, and refuges. 

1980

EXXON

VALDEZ

The supertanker spills

11 million gallons of crude

oil into Prince William

Sound, Alaska. 

1989

GREENHOUSE

EFFECT DETECTED

NASA climatologist James

Hansen tells the U.S. Con-

gress that carbon dioxide

and other heat-trapping

gases released by the

burning of fossil fuels

are already warming

the planet.

1988

SUPERFUND

PROGRAM

IS LAUNCHED

IN U.S.

The fund enables the

U.S. Environmental

Protection Agency to

clean up hazardous

waste sites. Polluters

must perform the

cleanup or pay for it. 

1980

RESCUING

CONDORS

The last 27 California condors

are taken into captivity for

breeding. A long recovery

begins; today more than 200

live in the wild once again.

1987

CHERNOBYL

NUCLEAR

ACCIDENT

A nuclear reactor explodes

at the Chernobyl power

plant in the Soviet Union.

The blast and radiation

kill 30 and force the evacu-

ation of nearly 1,100 square

miles—raising more doubts

about nuclear power.

1986

WORLD
POPULATION
IN 1980

4.5

BILLION

DISCOVERY OF THE
OZONE HOLE
Scientists detect severe depletion (red) of
the protective ozone layer above Antarctica.
The culprits: chlorofluorocarbons and
other chemicals.

1985

MONTREAL

PROTOCOL

World leaders agree to

phase out ozone-depleting

substances just a few

years after the ozone hole

is found. All nations ratify

the treaty.

1987

1980 S

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86 NATIONAL GEOGRAPHIC