World Scientists' Warning to Humanity -
Scientist Statement -
World Scientists' Warning to Humanity
Some 1,700 of the world's leading scientists, including the
majority of Nobel laureates in the sciences, issued this appeal
in November 1992.
The World Scientists'
Warning to Humanity was written and spearheaded by the late
Henry Kendall, former chair of UCS's board of directors.
Human beings and the natural world are on a collision course.
Human activities inflict harsh and often irreversible damage on
the environment and on critical resources.
If not checked, many
of our current practices put at serious risk the future that we
wish for human society and the plant and animal kingdoms, and
may so alter the living world that it will be unable to sustain
life in the manner that we know.
are urgent if we are to avoid the collision our present course
will bring about.
The environment is suffering critical stress:
Stratospheric ozone depletion threatens us with enhanced
ultraviolet radiation at the earth's surface, which can be
damaging or lethal to many life forms.
near ground level, and acid precipitation, are already
causing widespread injury to humans, forests, and crops.
Heedless exploitation of depletable ground water
supplies endangers food production and other essential human
Heavy demands on
the world's surface waters have resulted in serious
shortages in some 80 countries, containing 40 percent of the
Pollution of rivers, lakes, and ground
water further limits the supply.
Destructive pressure on the oceans is severe,
particularly in the coastal regions which produce most of
the world's food fish.
The total marine
catch is now at or above the estimated maximum sustainable
yield. Some fisheries have already shown signs of collapse.
heavy burdens of eroded soil into the seas also carry
industrial, municipal, agricultural, and livestock waste -
some of it toxic.
Loss of soil productivity, which is causing extensive
land abandonment, is a widespread by-product of current
practices in agriculture and animal husbandry.
Since 1945, 11
percent of the earth's vegetated surface has been degraded -
an area larger than India and China combined - and per
capita food production in many parts of the world is
Tropical rain forests, as well as tropical and temperate
dry forests, are being destroyed rapidly.
At present rates,
some critical forest types will be gone in a few years, and
most of the tropical rain forest will be gone before the end
of the next century.
With them will go large numbers of
plant and animal species.
The irreversible loss of species, which by 2100 may
reach one-third of all species now living, is especially
We are losing the
potential they hold for providing medicinal and other
benefits, and the contribution that genetic diversity of
life forms gives to the robustness of the world's biological
systems and to the astonishing beauty of the earth itself.
Much of this damage is irreversible on a scale of centuries,
appear to pose additional threats. Increasing levels of
gases in the atmosphere from human activities, including
carbon dioxide released from fossil fuel burning and from
deforestation, may alter climate on a global scale.
global warming are still uncertain - with projected effects
ranging from tolerable to very severe - but the potential
risks are very great.
Our massive tampering with the world's interdependent web of
life - coupled with the environmental damage inflicted by
deforestation, species loss, and climate change - could
trigger widespread adverse effects, including unpredictable
collapses of critical biological systems whose interactions
and dynamics we only imperfectly understand.
Uncertainty over the extent of these effects cannot excuse
complacency or delay in facing the threats.
The earth is finite. Its ability to absorb wastes and
destructive effluent is finite.
Its ability to
provide food and energy is finite. Its ability to provide for
growing numbers of people is finite. And we are fast approaching
many of the earth's limits.
practices which damage the environment, in both developed and
underdeveloped nations, cannot be continued without the risk
that vital global systems will be damaged beyond repair.
Pressures resulting from unrestrained population growth put
demands on the natural world that can overwhelm any efforts to
achieve a sustainable future. If we are to halt the destruction
of our environment, we must accept limits to that growth.
A World Bank estimate
indicates that world population will not stabilize at less than
12.4 billion, while the United Nations concludes that the
eventual total could reach 14 billion, a near tripling of
today's (1992) 5.4 billion.
But, even at this
moment, one person in five lives in absolute poverty without
enough to eat, and one in ten suffers serious malnutrition.
No more than one or a few decades remain before the chance to
avert the threats we now confront will be lost and the prospects
for humanity immeasurably diminished.
We the undersigned (below image), senior members of the world's
scientific community, hereby warn all humanity of what lies
A great change in our
stewardship of the earth and the life on it is required, if vast
human misery is to be avoided and our global home on this planet
is not to be irretrievably mutilated.
What We Must Do
Five inextricably linked areas must be addressed simultaneously:
We must bring
environmentally damaging activities under control to restore
and protect the integrity of the earth's systems we depend
We must, for example, move away from fossil fuels to more
benign, inexhaustible energy sources to cut greenhouse gas
emissions and the pollution of our air and water. Priority
must be given to the development of energy sources matched
to Third World needs - small-scale and relatively easy to
We must halt deforestation, injury to and loss of
agricultural land, and the loss of terrestrial and marine
plant and animal species.
We must manage resources crucial to human welfare more
We must give high priority to efficient use of energy,
water, and other materials, including expansion of
conservation and recycling.
We must stabilize population.
This will be possible
only if all nations recognize that it requires improved social
and economic conditions, and the adoption of effective,
voluntary family planning.
We must reduce
and eventually eliminate poverty.
We must ensure sexual equality, and guarantee women control
over their own reproductive decisions.
Developed Nations Must Act Now
The developed nations are the largest polluters in the world
today. They must greatly
reduce their overconsumption, if we are to reduce pressures on
resources and the global environment.
The developed nations have
the obligation to provide aid and support to developing nations,
because only the developed nations have the financial resources
and the technical skills for these tasks.
Acting on this recognition is not altruism, but enlightened
industrialized or not, we all have but one lifeboat.
No nation can escape
from injury when global biological systems are damaged.
No nation can escape
from conflicts over increasingly scarce resources. In addition,
environmental and economic instabilities will cause mass
migrations with incalculable consequences for developed and
undeveloped nations alike.
must realize that environmental damage is one of the gravest
threats they face, and that attempts to blunt it will be
overwhelmed if their populations go unchecked.
The greatest peril is
to become trapped in spirals of environmental decline, poverty,
and unrest, leading to social, economic, and environmental
Success in this global endeavor will require a great reduction
in violence and war.
Resources now devoted
to the preparation and conduct of war - amounting to over $1
trillion annually - will be badly needed in the new tasks and
should be diverted to the new challenges.
A new ethic is required - a new attitude towards discharging our
responsibility for caring for ourselves and for the earth. We
must recognize the earth's limited capacity to provide for us.
We must recognize its
fragility. We must no longer allow it to be ravaged.
This ethic must
motivate a great movement, convincing reluctant leaders and
reluctant governments and reluctant peoples themselves to effect
the needed changes.
The scientists issuing this warning hope that our message will
reach and affect people everywhere.
We need the help of
We require the
help of the world community of scientists - natural, social,
economic, and political.
We require the help of the world's business and industrial
We require the help of the world's religious leaders.
We require the help of the world's peoples.
We call on all to join us in this task.
We Need Your Support,
...to Make Change Happen.
We can reduce global
warming emissions and ensure communities have the resources they
need to withstand the effects of climate change - but not
Your generous support
helps develop science-based solutions for a healthy, safe, and