Planetary Boundaries and Human Prosperity
APR 28, 2015STOCKHOLM – The future of humanity will depend on mastering a balancing act. The challenge will be to provide for the needs of more than ten billion people while safeguarding our planetary life-support systems. Recent scientific insights have made us better equipped than ever to strike that balance. Doing so will be our generation’s great task.
Ending poverty has
become a realistic goal for the first time in human history. We have the
ability to ensure that every person on the planet has the food, water,
shelter, education, health care, and energy needed to lead a life of
dignity and opportunity. But we will be able to do so only if we
simultaneously protect the earth’s critical systems: its climate, ozone layer, soils, biodiversity, fresh water, oceans, forests, and air. And those systems are under unprecedented pressure.
For the last 10,000
years, the earth’s climate has been remarkably stable. Global
temperatures rose and fell by no more than one degree Celsius (compared
with swings of more than eight degrees Celsius during the last ice age),
and resilient ecosystems met humanity’s needs. This period – known as
the Holocene – provided the stability that enabled human civilization to
rise and thrive. It is the only state of the planet of which we know
that can sustain prosperous lives for ten billion people.
But humans have now
become the single largest driver of ecosystem change on earth, marking
the start of a new geological age that some call the Anthropocene.
Scientists argue over the exact starting point of this epoch, but it
can be dated to somewhere around 1945, when modern industry and
agriculture began to expand briskly. In the future, geologists will see
telltale markers like radioactive carbon – debris from nuclear blasts –
and plastic waste scattered across the planet’s surface and embedded in
rock.
More recently, human activity has undergone what is being called the Great Acceleration:
the rapid intensification of resource consumption and ecological
degradation. We risk disrupting the earth’s critical systems, and with
them modern civilization itself.
The planet’s response
to our pressures is likely to be unpredictable. Indeed, the surprises
have already begun. As we overdraw on our planet’s accounts, it is
starting to levy penalties on the global economy, in the form of extreme
weather events, accelerated melting of ice sheets, rapid biodiversity
loss, and the vast bleaching of coral reefs.
We face an urgent
need to define a safety zone that prevents us from pushing our planet
out of the unusually benevolent Holocene state. The Planetary Boundaries framework,
which a group of scientists, including one of us (Johan), first
published in 2009, does just that. It draws on the best science to
identify the key planetary processes regulating the earth’s ability to
sustain Holocene-like conditions. For each of those processes, it
proposes a boundary – a quantitative ceiling – beyond which we risk
inducing abrupt changes that could push our planet into a state that is
more hostile to humanity.
These nine boundaries
include climate change, ozone depletion, ocean acidification,
interference in the global nitrogen and phosphorus cycles, land-use
change, global freshwater use, biosphere integrity, air pollution, and
novel entities (such as organic pollutants, radioactive materials,
nanomaterials, and micro-plastics). Worryingly, our most recent update
in January, which confirms the nine boundaries and improves their
quantifications further, indicates that humanity has already transgressed four: climate change, nitrogen and phosphorus use, biodiversity loss, and land-use change.
Our challenge is to
bring the earth’s systems back within the safety zone, while
simultaneously ensuring that every person has the resources he or she
needs to lead a happy and fulfilling life. Between these planetary and
social boundaries lies humanity’s safe and just operating space: the limits we must respect if we are to create a world that is ecologically resilient and free of poverty.
Meeting these goals
will require a far more equitable distribution of the planet’s resources
and far greater efficiency in how we use them. If we are to ensure that
our planet remains one on which all of humanity can thrive, we will
have to pursue a new paradigm of prosperity.
Johan Rockström is Professor in Global Sustainability.
Kate Raworth is Senior Visiting Research Associate at Oxford
University’s Environmental Change Institute, Senior Associate of the
Cambridge Institute for Sustainability Leadership, and a member of the
Club of Rome.
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