Uncertainty, Lags, and Nonlinearity: Challenges to Governance in a Turbulent World Thomas Homer-Dixon CIGI Chair of Global Systems Balsillie School of

Uncertainty, Lags, and Nonlinearity:Challenges to Governance in a Turbulent World

Thomas Homer-Dixon

CIGI Chair of Global Systems

Balsillie School of International Affairs

Waterloo,Canada

May 7 2009

UNCERTAINTYUNCERTAINTY

LAGSLAGS

NONLINEARITYNONLINEARITY

OPENNESSOPENNESS


LAGSLAGS


OPENNESSOPENNESS


LAGSLAGS


OPENNESSOPENNESS

We need to shift from seeing the world We need to shift from seeing the world as composed mainly ofas composed mainly of

MACHINESMACHINES

to seeing it as composed mainly ofto seeing it as composed mainly of

COMPLEX SYSTEMSCOMPLEX SYSTEMS

Whereas MACHINESWhereas MACHINES

• can be taken apart, analyzed, and fully can be taken apart, analyzed, and fully understood (they are no more than the sum understood (they are no more than the sum of their parts)of their parts)

• exhibit “normal” or equilibrium patterns of exhibit “normal” or equilibrium patterns of behaviorbehavior

• show proportionality of cause and effect, show proportionality of cause and effect, andand

• can be managed because their behavior can be managed because their behavior predictablepredictable . . .. . .

COMPLEX SYTEMSCOMPLEX SYTEMS

• are more than the sum of their parts (they are more than the sum of their parts (they have have emergentemergent properties) properties)

• can flip from one pattern of behavior to can flip from one pattern of behavior to another (they have another (they have multiple equilibriums)multiple equilibriums)

• show disproportionality of cause and effect show disproportionality of cause and effect (their behavior is often (their behavior is often nonlinearnonlinear, because , because of of feedbacks feedbacks and and synergiessynergies), and), and

• cannot be easily cannot be easily managedmanaged because their because their behavior is often behavior is often unpredictableunpredictable..

We’re moving from a world ofWe’re moving from a world of

RISKRISK

to a world ofto a world of

UNCERTAINTYUNCERTAINTY(unknown unknowns)(unknown unknowns)

So, we must move from “management” toSo, we must move from “management” to

Complex AdaptationComplex Adaptation

Battisti and Naylor, “Historical warnings of future food insecurity with unprecedented seasonal heat.”Science (9 January 2009): 240-44

Battisti and Naylor, “Historical warnings of future food insecurity with unprecedented seasonal heat.”Science (9 January 2009): 240-44

IPCC 2007


LAGSLAGS


OPENNESSOPENNESS

LAGSLAGS

• Between emission and climate responseBetween emission and climate response

• Between cuts to emissions and reduction of Between cuts to emissions and reduction of warmingwarming

• Between policy decision to change energy Between policy decision to change energy infrastructure and completion of this changeinfrastructure and completion of this change

“ [We show] that to hold climate constant at a given global temperature requires near zero future carbon emissions. . . . As a consequence, any future anthropogenic emissions will commit the climate system to warming that is essentially irreversible on centennial timescales.”Matthews, H. D., and K. Caldeira (2008), “Stabilizing climate requires near-zero emissions,” Geophys. Res. Lett.

““[The] climate change that takes place due to increases in carbon dioxide concentration is largely irreversible for 1,000 years after emissions stop. Following cessation of emissions, removal of atmospheric carbon dioxide decreases radiative forcing, but is largely compensated by slower loss of heat to the ocean, so that atmospheric temperatures do not drop significantly for at least 1,000 years. Among illustrative irreversible impacts that should be expected if atmospheric carbon dioxide concentrations increase from current levels near 385 parts per million by volume (ppmv) to a peak of 450–600 ppmv over the coming century are dry-season rainfall reductions in several regions comparable to those of the ‘‘dust bowl’’ era and inexorable sea level rise.”

Solomon et al, “Irreversible climate change due to carbon dioxide emissions,” Solomon et al, “Irreversible climate change due to carbon dioxide emissions,” PNAS (February 10 2009).

Hansen, Atmos. Chem. Phys. 7 (2007): 2287-2312.


LAGSLAGS


OPENNESSOPENNESS

0

0.05

0.1

0.15

0.2

0.25

105001100011500120001250013000

Years before Present

Ice

Acc

umul

atio

n R

ate

(m

eter

s pe

r ye

ar)

More rapid warming at polesMore rapid warming at polesOne reason: Ice-albedo feedbackOne reason: Ice-albedo feedback

Atmosphericwarming

Lower reflectivityof ocean surface

Melting ofice

Increased oceanabsorption of sun’s energy

radiativepositive feedback,

fast

20084.52 mK2

Jakobshavn Ice Stream in Greenland

Discharge from major Greenland ice streams is accelerating markedly.

Source: Prof. Konrad Steffen, Univ. of Colorado

Atmosphericwarming

Rotting and burningof organic

matter

Death offorests

Release ofCO2

carbon cyclepositive feedback,

potentially fast

Atmosphericwarming

Increasedairbornefraction

Decreasedefficiency ofcarbon sinks


slow

• Up to 30 percent decrease in the efficiency of the Southern Ocean sink over the last 20 years

• Strengthening of the winds around Antarctica increases exposure of carbon-rich deep waters

• Strengthening of the winds due to global warming and the ozone hole

Declining efficiency of the ocean sink

Le Quéré et al. 2007, Science

Atmosphericwarming

Rottingof organic

matter

Melting ofpermafrost

Release ofCH4

and CO2


potentially fast

Documents

Uncertainty, Lags, and Nonlinearity: Challenges to Governance in a Turbulent World Thomas Homer-Dixon CIGI Chair of Global Systems Balsillie School of