extra_rockstrom2.pdf

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Exploring the

SafeOperating

Space forHumanity

Prof. Johan RockstrmStockholm Resilience CentreStockholm Environment Institute

Sustainability: prepare for impactUtrecht University

3rd December 2009

Planetary Boundaries


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A biosphere shaped by humanity


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Human growth

20/80 dilemma

Ecosystems60 % loss dilemma

Climate550/450/350

dilemma

Surprise99/1 dilemma

The Quadruple

Squeeze


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Humanitys period of grace the last 10000 years


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Kaufman, Darrell S., et al. 2009. Recent

Warming Reverses Long-Term Arctic

Cooling. Science, September 4, 2009

Steffen, W., et al. 2004

Humanity in the

Anthropocene


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5

4

3

2

1

0


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Critical transitions or regime shifts


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1

2

overfishing, coastal

eutrophication

phosphorous accum-

ulation in soil and mud

fire prevention

3

state shift

disease,

hurricane

flooding, warming,

overexploitationof predators

good rains, continu-

ous heavy grazing

coral dominance

clear water

grassland

4

algal dominance

turbid water

shrub-bushland

Valuable Ecosystem Services Loss of ecosystem services

(Desirable) (Undesirable)


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The risk of Catastrophic Tipping Points


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The Resilience of the Earth System


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Our precarious predicament

We have our foot on the accelerator

driving towards the Abyss...

Ban Ki-moon Secretary General of the UNSept 2009


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Planetary

Boundaries:Exploring the safeoperating space for

humanity in theAnthropocene(Nature, 461 : 472

475, Sept 24 - 2009)


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1. Earth System and sustainability science(Understanding Earth System processes; ICSU,

IGBP, ESSP, IPCC, MEA, evolution ofsustainability science)

2. Scale of human action in relation to the

capacity of the planet to sustain it(Kenneth Boulding Spaceship Earth, Herman

Daly, Club of Rome, Ecological Economics

reserach agenda, Ecological Footprint...)

3. Shocks and Abrupt change in Social-

Ecological systems from local to global

scales

(Resilience, GAIA, tipping elements, guardrails...)

PlanetaryBoundaries

concept

PB concept rests on three branches

of Scientific inquiry


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From:Limits to growth

Carrying capacity

Guardrails

Tipping Elements

To:Planetary Boundaries


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Two different types of

planetary boundary processes

2. No known global threshold effect1. Crit ical continental to global threshold


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Boundary

character

Scale of process

Processes

with global scale

thresholds

Slow processes

without known

global scalethresholds

Climate Change

Ocean Acidification

Systemic

processes at

planetary scale

Stratospheric Ozone

Global P and N cycles

Atmospheric Aerosol Loading

Freshwater Use

Land Use Change

Biodiversity Loss

Aggregated

processes fromlocal/regional scale

Chemical Pollution


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Climate Change< 350 ppm CO2< 1W m

2

(350 500 ppm CO2 ;

1-1.5 W m2)

Ocean acidificationAragonite saturation

ratio > 80 % above pre-

industrial levels(> 80% - > 70 %)

Ozone depletion< 5 % of Pre-Industrial 290 DU

(5 - 10%)

Global Freshwater Use


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Climate Changewhat is required to avoid the crossing of critical

thresholds that separate qualitatively different climatesystem states

We suggest boundary valuesof 350 ppm CO2 and 1 W m

-2

above pre-industrial level


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Already Committed Global Warming

Uncertain uncertainty


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21

Uncertain uncertainty

ref: Baer and Mastrandrea (2006)

3 C 6 C

T t i l d


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0

2

4

6

8

10

12

14

16

1970 1980 1990 2000 2004

CO2fromfossilfuelsandothersourcesCO2fromlandusechangeCH4fromagriculture,wasteandenergyN2Ofromagriculture andothersFgases

Terrestrial and

Marine Carbonsinks

Adapted from Canadell et al., 2007

0

1

2

3

45

6

7

8

9

10

GtCarbon/yr

ocean

land

Ocean acidification


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Ocean acidificationChallenge to marine biodiversity and ability of oceans to

function as sink of CO2

Southern Ocean and Arcticocean projected to become

corrosive to aragonite by

2030-2060

Turley et al 2006


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Ocean acidificationSetting the boundary:

Globally surface aragonite saturationstate is declining (arag= 3.44 to a

current value of 2.9)

2CO2 arag= 2.29

Proposed boundary > 80 % pre-

industrial arag= 2.75


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From R. Buddemeier, based on Kleypas et al. 1999

Rate of Biodiversity Loss


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Rate of Biodiversity LossAvoid large scale irreversible loss of functional

diversity and ecological resilience

The current and projected rate of biodiversity lossconstitutes the sixth major extinction event in the

history of life on Earth the first to be driven byhuman activities on the planet

Biodiversity plays a key role for functional diversityand thereby ecosystem resilience

Humans have increased the rate of speciesextinction by 100-1,000 times the background ratesthat were typical over Earths history

Average global extinction rate projected to increase

another 10-fold, to 1,000-10,000 E/MSY during thecurrent century


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Biodiversity LossSetting the boundary:

Suggesting a safe planetary boundary

(here placed at 10 E/MSY)

within an order of magnitude of the

natural background rate

limate Oz


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Nitrogen

flow

Agriculturallanduse

Oce

an

acidity

Fresh

wate

r

cons

umption

Pho

sphor

us

flow

Clima

Change

Atmospheric

aerosolload

Chemical

pollution

Ozonedepletion

B

iodiversity

loss ?

?

50-60

70-80

Latest

data

90-00

Pre-

Ind.

?

??

?

C l i


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Conclusions

In the Anthropocene Humanity is, for the first time,influencing hard-wired processes at the Earth Systemscale

We define the Holocene as the desired stable stateproviding necessary environmental pre-conditions forhuman development

We need a new approach to global sustainabil ity and

development that builds on conceptual and knowledgeadvancements such as the limits to growth work,tipping elements, guardrails, carrying capacities.Scientific insights from research on resilience and complex systems, and

Earth System Science, on the risks of human induced tipping points in amultitude of Earth system processes and sub-systems

We propose that a Planetary Boundary framework mayprovide one step towards this necessary redefinition


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The Planetary Boundaries analysis presented in Nature isa proof-of-concept analysis, with many of theproposed boundaries being first best guesses. Manyuncertainties remain, and will continue to remain.

What we suggest is a challenge to the Earth System

Science community to advance further research on Earthsystem interactions and non-linear dynamics

Large Knowledge gaps remain

Understanding of threshold dynamics Boundary interactions and feedbacks

Spatial variability and patchiness may require global

and regional boundaries Allowed overshoot time unclear


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No doubt, a Planetary Boundaries approach to sustainabledevelopment would have profound implications forgovernance and policy across scales. Large scientific

challenges to address the human dimensions and governance implications ofdevelopment within Planetary Boundaries

Despite uncertainties on allowed overshoot before large

discontinuities, we have enough evidence to act now.Time is running out on several of the Planetary Boundaries, and themomentum of driving forces tremendous. This is a first attempt to define thesafe space for human development, which may prove critical in turbulent timesahead.


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Land System Change


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Land System ChangeAvoid unsustainable land system change

predominantly from intensive agricultural use

Threat to biodiversity and undermining ofregulatory capacity of ecosystems

Setting the boundary: No more than 15 %

of the global ice-free land surface shouldbe converted to cropland (12% today)

Global Freshwater Use


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Global Freshwater UseAvoid water induced environmental change at regional

scale

Humans now alter global runoffflows, through withdrawals of bluewater, and changes in greenwater flows, affecting waterpartitioning and moisturefeedback

Physical water scarcity whenwithdrawals exceed 5000 6000km3 yr-1

Final availability of runoffdetermined by consumptive useof green and blue water flows

Consumptive use of blue water an

aggregate control variable withboundary set at < 4000 km3 yr-1

Pl I i


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Peter Snyder et al. 2004

Planetary Inter-connections


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Ozone depletion


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Ozone depletionAvoiding the risk of large impacts for humans and ecosystem

from thinning of extra-polar ozone layer

Antarctic ozone depletion a

classic example of anunexpected crossing of athreshold

Our framing on extra-polarozone layer depletion

Identifying a thresholdremains uncertain

a less than 5% decrease incolumn ozone levels for anyparticular latitude

Chemical Pollution


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Chemical PollutionSteer away from irreversible impacts on living

organisms

Global, ubiquitous impact on the physiological

development and demography of humans andother organisms with ultimate impacts onecosystem functioning and structure

By acting as a slow variable that affects other

planetary boundaries (e.g., rate of biodiversityloss)

2 complementary approaches: amounts ofpersistent pollutants with global distribution

(e.g., mercury); Effects of chemical pollution onliving organisms

Difficult to find an appropriate aggregatecontrol variable. Close interactions with

Aerosol loading; may require sub-boundariesbased on sub-impacts/categories of chemicals

Pl t I t ti


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Peter Snyder et al. 2004

Planetary Inter-connections


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