‘industrial revolution’ which consisted of interdependent transformations in different
sectors and places.
Why?
Earth and climate scientists tell us that the transformations required for sustainability
need to be achieved quickly. A key feature of their message is urgency. Continuing
on the current path would mean soon reaching tipping points beyond which life
on earth would suffer irreversible damage. Such ideas on the depth and speed of the
required transformations are increasingly influenced by the concept of ‘planetary
boundaries’ (Rockström et al., 2009). These boundaries define ‘a safe operating
space for humanity’. A breach of these ‘planetary guard rails’ (WBGU, 2011) would
give rise to intolerable consequences so significant that even major advances in
other fields could not compensate for the damage.
Rockström et al. (2009) identify nine planetary boundaries that human-induced
changes threaten to breed: climate change, ocean acidification, stratospheric ozone
depletion, global phosphorus and nitrogen cycles, biodiversity loss, global freshwater
scarcity, land-system change, atmospheric aerosol loading and chemical pollution.
Seven of the nine boundaries are quantified, but these seven cannot therefore be
considered firm thresholds. The indicators of change and their exact values chosen
by Rockström et al. are for the most part arbitrary. Moreover, boundaries do not
always apply globally. Local circumstances can ultimately determine how soon water
shortages or biodiversity loss reach a critical threshold (Editorial of Nature, 2009).
In short, the claimed urgency does not apply equally to all planetary boundaries and
locations.
Melissa Leach in this book goes a step further and expresses concern that the
planetary boundaries discourse invites top-down approaches and technocratic
fixes. I agree that there is a danger that the search for solutions is depoliticized,
but there is also the danger of undermining a collective scientific undertaking
and playing into the hands of those who deny the underlying problem. While
uncertainties remain, the concept of planetary boundaries seems a constructive
attempt to define the limits to economic growth. And for some boundaries the
evidence is fairly robust – notably, the one concerning climate change due to
increasing carbon emissions. The scientific and policy debate on mitigating climate
change has exploded partly because there is a deadline for achieving the trans -
formation from a high to low-carbon economy. Climate scientists have produced
a timetable for reducing these carbon emissions (IPCC, 2007, 2013): the most
common reference point is that global emissions must fall by an average of 50 per
cent below 1990 levels by 2050, in order to avoid more than two degrees of
global warming. Intermediate carbon reduction targets have been set for 2020 and
2030. While the precise dates and figures can be questioned, there is increasing scientific consensus that with each passing year of continued high emissions,
the prospect of avoiding climate chaos sinks and the cost of dealing with the
consequences rises (Stern, 2007).
172 Hubert Schmitz
sectors and places.
Why?
Earth and climate scientists tell us that the transformations required for sustainability
need to be achieved quickly. A key feature of their message is urgency. Continuing
on the current path would mean soon reaching tipping points beyond which life
on earth would suffer irreversible damage. Such ideas on the depth and speed of the
required transformations are increasingly influenced by the concept of ‘planetary
boundaries’ (Rockström et al., 2009). These boundaries define ‘a safe operating
space for humanity’. A breach of these ‘planetary guard rails’ (WBGU, 2011) would
give rise to intolerable consequences so significant that even major advances in
other fields could not compensate for the damage.
Rockström et al. (2009) identify nine planetary boundaries that human-induced
changes threaten to breed: climate change, ocean acidification, stratospheric ozone
depletion, global phosphorus and nitrogen cycles, biodiversity loss, global freshwater
scarcity, land-system change, atmospheric aerosol loading and chemical pollution.
Seven of the nine boundaries are quantified, but these seven cannot therefore be
considered firm thresholds. The indicators of change and their exact values chosen
by Rockström et al. are for the most part arbitrary. Moreover, boundaries do not
always apply globally. Local circumstances can ultimately determine how soon water
shortages or biodiversity loss reach a critical threshold (Editorial of Nature, 2009).
In short, the claimed urgency does not apply equally to all planetary boundaries and
locations.
Melissa Leach in this book goes a step further and expresses concern that the
planetary boundaries discourse invites top-down approaches and technocratic
fixes. I agree that there is a danger that the search for solutions is depoliticized,
but there is also the danger of undermining a collective scientific undertaking
and playing into the hands of those who deny the underlying problem. While
uncertainties remain, the concept of planetary boundaries seems a constructive
attempt to define the limits to economic growth. And for some boundaries the
evidence is fairly robust – notably, the one concerning climate change due to
increasing carbon emissions. The scientific and policy debate on mitigating climate
change has exploded partly because there is a deadline for achieving the trans -
formation from a high to low-carbon economy. Climate scientists have produced
a timetable for reducing these carbon emissions (IPCC, 2007, 2013): the most
common reference point is that global emissions must fall by an average of 50 per
cent below 1990 levels by 2050, in order to avoid more than two degrees of
global warming. Intermediate carbon reduction targets have been set for 2020 and
2030. While the precise dates and figures can be questioned, there is increasing scientific consensus that with each passing year of continued high emissions,
the prospect of avoiding climate chaos sinks and the cost of dealing with the
consequences rises (Stern, 2007).
172 Hubert Schmitz