1

Uncertainty, Lags, Uncertainty, Lags, Nonlinearity and Nonlinearity and Feedbacks: Feedbacks: New Terms for New Terms for a New Millenniuma New MillenniumWe must transition out of our 19We must transition out of our 19thth century century

view of Technology as basic engineering view of Technology as basic engineering works and into a new view of Technology works and into a new view of Technology as an agent which changes material and as an agent which changes material and energy flows within the earth.energy flows within the earth.

Then we must develop an appropriate Then we must develop an appropriate management plan in the wake of management plan in the wake of increasing unknown responses.increasing unknown responses.

Are we Brave Enough to do this?Are we Brave Enough to do this?

UNCERTAINTYUNCERTAINTY

LAGSLAGS

NONLINEARITYNONLINEARITYFEEDBACKSFEEDBACKS

33

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

MACHINES (the industrial MACHINES (the industrial revolution)revolution)

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

COMPLEX SYSTEMS (chaos COMPLEX SYSTEMS (chaos introduced by Humans)introduced by Humans)

44

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, and (i.e. they are linear systems)and (i.e. they are linear systems)

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

55

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 disproportionally of cause and effect show disproportionally 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 AdaptationClimate Change Climate Disruption Climate Volatility

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

Statistical Outcomes

IPCC 2007

New Fields of Study Needed to Help With Management

UNCERTAINTYUNCERTAINTY

LAGSLAGS

NONLINEARITYNONLINEARITYFEEDBACKSFEEDBACKS

1414

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.

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

UNCERTAINTYUNCERTAINTY

LAGSLAGS

NONLINEARITYNONLINEARITYFEEDBACKSFEEDBACKS

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)

A Non-Linearity

20084.52 mK2

A Non Linearity

Jakobshavn Ice Stream in Greenland

Discharge from major Greenland ice streams is accelerating markedly.

Source: Prof. Konrad Steffen, Univ. of Colorado

• Up to 40 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

UNCERTAINTYUNCERTAINTY

LAGSLAGS

NONLINEARITYNONLINEARITYFEEDBACKSFEEDBACKS

Global Air Temperature

Increases

IncreasedGreenhouseAbsorption

IncreasedWater Vapor

In Atmosphere

Water vaporpositive feedback

Increased Carbon Dioxide amounts

More rapid warming at polesMore rapid warming at polesIce-albedo feedbackIce-albedo feedback

Atmosphericwarming

Lower reflectivityof ocean surface

Melting ofice

Increased oceanabsorption of sun’s energy

radiativepositive feedback,

fast

Atmosphericwarming

Increasedemissions

Decreasedefficiency ofcarbon sinks

emissions cyclepositive feedback,

slow

Atmosphericwarming

Rotting and burningof organic

matter

Death offorests

Release ofCO2

Accelerated carbon cycle

positive feedback,potentially fast

Atmosphericwarming

Rottingof organic

matter

Melting ofpermafrost

Release ofCH4

and CO2

Methane cyclepositive feedback,

potentially fast