Page 33 - Environment: The Science Behind the Stories

Sustainability and Our Future

Throughout this book you will encounter environmental scientists
asking questions, testing hypotheses, conducting experiments, Brazil
analyzing data, and drawing conclusions about the causes (2.9 ha)
and consequences of environmental change. Environmental
scientists who study the condition of our environment and the Canada
consequences of our impacts are addressing the most centrally United (6.4 ha)
important issues of our time. States Mexico
(7.2 ha) (3.3 ha)
Afghanistan
Achieving sustainable solutions is vital (0.5 ha)

The primary challenge in our increasingly populated world is
how to live within our planet’s means, such that Earth and its
resources can sustain us—and all life—for the future. This is the
challenge of sustainability, a guiding principle of modern envi- World average Indonesia
(2.7 ha)
ronmental science. Sustainability means leaving our children Haiti (1.1 ha)
and grandchildren a world as rich and full as the world we live in (0.6 ha)
now. It means conserving Earth’s resources so that our descend-
ants may enjoy them as we have. It means developing solutions
that work in the long term. Sustainability requires maintaining China
ecological systems, because we cannot sustain human civili- (2.1 ha)
zation without sustaining the natural systems that nourish it. Israel India
We can think of our planet’s resources as a bank account. (4.0 ha) (0.9 ha)
France
If we deplete resources, we draw down the bank account. How- (4.9 ha)
ever, we can choose instead to use the interest and leave the
principal intact so that we can continue using the interest far
into the future. Currently we are drawing down Earth’s natural Rwanda
(0.7 ha)
capital, its accumulated wealth of resources. Recall (p. 23) that
one research group estimates that we are withdrawing our plan-
et’s natural capital 50% faster than it is being replenished. To FIGURE 1.12 The citizens of some nations have much larger
live off nature’s interest—its replenishable resources—is sus- ecological footprints than the citizens of others. Ecological foot-
tainable. To draw down resources faster than they are replaced prints for average citizens of several nations are shown, along with
is to eat into nature’s capital—the bank account for our planet the world’s average per capita footprint of 2.7 hectares. One hectare
and our civilization—and we cannot get away with this for long. (ha) = 2.47 acres. Data from Global Footprint Network, in: WWF, 2012. Living
planet report 2012. WWF International, Gland, Switzerland.
Population and consumption drive Which nation has the largest footprint, and how many times
larger is it than that of the nation with the smallest footprint?
environmental impact

We modify our environment in many ways, but the steep and sud- WEIGHING THE ISSUES
den rise in human population (Chapter 8) has amplified nearly all
of our impacts. We add about 80 million people to the planet each ECOLOGICAL FOOTPRINTS What do you think accounts for
year—that’s over 200,000 per day. The rate of population growth the variation in sizes of per capita ecological footprints among
is now slowing, but our absolute numbers continue to increase. societies? Do you feel that nations with larger footprints have
Our consumption of resources has risen even faster than a moral obligation to reduce their environmental impact, so
our population. The modern rise in affluence has been a posi- as to leave more resources available for nations with smaller
tive development for humanity, and our conversion of the plan- footprints? Why or why not?
et’s natural capital has made life better for most of us so far.
However, like rising population, rising per capita consumption
magnifies the demands we make on our environment. Our dramatic growth in population and consumption is
The world’s citizens have not benefited equally from our intensifying the many environmental impacts we examine in
overall rise in affluence. Today the 20 wealthiest nations boast this book, including erosion and other impacts from agricul-
over 55 times the per capita income of the 20 poorest nations— ture (Chapters 9 and 10), deforestation (Chapter 12), toxic
three times the gap that existed just two generations ago. The substances (Chapter 14), fresh water depletion (Chapter 15),
ecological footprint of the average citizen of a developed nation fisheries declines (Chapter 16), air and water pollution (Chap-
such as the United States is considerably larger than that of the ters 15–17), waste generation (Chapter 22), mineral extrac-
average resident of a developing country (FIGURE 1.12). Within tion and mining impacts (Chapter 23), and of course, global
the United States, the richest 10% of people claim fully half the climate change (Chapter 18). These impacts degrade our
32 income, and the richest 1% claim nearly a quarter of all income. health and quality of life, and they alter the ecosystems and

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