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Earth Systems Engineering and Management

CEE 400

Week 5: Complex Systems

Earth Systems Engineering and Management

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Complex Systems: Terms

  • Systems are groups of interacting, interdependent parts linked together by exchanges of energy, matter and information
  • Complex systems are characterized by:
  • Strong (usually non-linear) interactions between the parts
  • Complex feedback loops that make it difficult to distinguish cause from effect
  • Significant time and space lags, discontinuities, thresholds, and limits
  • Operation far from equilibrium in a state of constant adaptation to changing conditions (at the edge of deterministic chaos)

Adapted from R. Costanza, L. Wainger, C folk, and K. Maler, “Modeling Complex Ecological Economic,” BioScience 43(8): 545-55

Four Types of Complexity

  • Static complexity (or just complicated): many nodes and links (a 747 sitting on the ground)
  • Dynamic complexity: system operating through time (747 in flight, controlled by air traffic control)
  • Wicked complexity: integrates human systems (global air transport as a system)
  • Earth systems complexity: integrated built/natural/human systems at regional and global scale (e.g., effect of 747 on disease patterns, and on eco-touorism)

Evolution of Complex Adaptive Systems

  • All complex systems evolve in response to changing boundary conditions and internal dynamics – so known as “Complex Adaptive Systems”. Evolution occurs as the result of three mechanisms linked in complicated ways:

  • Information storage and transmission
  • Mutation (generation of new alternatives for system agents
  • Selection among alternative based on performance given internal states and external boundary conditions

Where Complex Adaptive Systems Live

  • If too many strong linkages among parts of a system, it cannot adapt; any mutation is rapidly damped out.
  • If not enough linkages, also cannot adapt; mutation can’t be preserved in new system state.
  • Therefore, CASs live between stasis and randomness

Human Systems vs. Non-Human Systems
(The “Wicked” vs. The “Tame”)

Wicked Systems:

1. Policy problems cannot be definitively described

2. There is nothing like an indisputable public good

3. There are no objective definitions of equity

4. Policies for social problems cannot be meaningfully correct or false

5. There are no “solutions”in the sense of definitive, objective answers

6. There is no optimality

Source: H.W.J. Rittel and M. M.Webber, “Dilemmas in a General Theory Planning,” Policy Scenes 4 (1973), pp. 155-169

Policy Implications
of Simple (S) vs Complex (C) Systems

Function as Displayed by System

Information

Centralized command-and-control feasible

System management by adjusting forcing behavior; command-and-control contraindicated

Causality

Centralized command-and-control to endpoint (effect) feasible

Function

Type

Policy Implication

S

Centralized; system is “knowable”

C

Information diffused throughout the system; some embedded in system structure; system too complex to be “known”

S

Linear; cause and effect east to determine

C

Causes and effects cannot be linked in most cases

Cannot be sure of actual impact on system of any policy initiative

Policy Implications
of Simple (S) vs Complex (C) Systems (Cont)

Function

Type

Policy Implication

S

Predictable and relatively linear

C

Highly non-linear and may be discontinuous; not predictable a priori

S

Rational centralized control is possible and effective

C

Causes and effects cannot be linked in most cases

Single, fully responsible entity with authoritarian power can control system (e.g., U.S. EPA)

Response to Forcing

Rigid regulatory structures both o.k. (because out come predictable) and politically preferable (because can’t be gamed)

Policy once in place must be very flexible, so can be changed as systems response dictates: arbitrariness and gaming avoided by adherence to appropriate set of metrics

Responsible management entity adjusts forcing functions (e.g., taxes or fees) and monitor results; direct control of system towards endpoint eschewed metrics

Function as Displayed by System

Control Mechanisms

Policy Implications
of Simple (S) vs Complex (C) Systems (Cont)

S

May not be necessary because performance measured by attaining endpoint, not system state

C

Defined in process or performance terms, and not fixed because the constantly evolving nature of the system

Endpoints are metrics

Manage process to improve performance against metrics; metrics critical to public/political acceptance of management process; choice of appropriate set of metrics essential to policy evaluate and subject to improvement as well

Metrics

Function

Type

Policy Implication

S

Defined as static terms, and achievable, not path dependent

C

Defined in process or performance terms, and not fixed because of constantly evolving nature of systems

Endpoint

Command-and-control management to endpoint o.k.

No defined endpoint; manage system to achieve desired emergent behavior

Function as Displayed by System

Policy Implications
of Simple (S) vs Complex (C) Systems (Cont)

Function

Type

Policy Implication

S

Produce endpoint

C

Maintain system stability and integrity over time

Existence

Can minimize specific insult (e.g., lead dispersion from use in gasoline); cannot lead to or support achievability of sustainability

Policy focus as a whole must be on system, not arbitrary components; metrics focus on stability and systems dynamics, not throughput

Function as Displayed by System

Complex System Case Study:

Water

Water as Earth System:
What is it?

  • It is a material
  • It is a commodity (a material that can be owned)
  • It is a legal construct – “water rights”
  • It is a cultural construct – “water as human right”
  • It is a technological construct (technology makes “potable water” from “sewage”)

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Water as Earth System

  • It is transport (in Roman empire, estimates that moving a given load 1 mile by oxcart = 5.7 miles by river = 57 miles by sea)
  • Development economics theorizes that inland countries are disadvantaged because of lack of access to ocean shipping
  • The railroad made up for this later in some countries
  • It is energy
  • It is political power (cf. water wars)
  • Essential for life (critical environmentally)

Dada from A. Beattie, 2009, False Economy, London: Penguin))

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Water as Earth System

  • It is something that can be used, but not used up (form and quality matter)

  • Availability in a particular circumstance is a matter of pricepoint, infrastructure and power, not “natural” constraints.

  • Distribution challenges arise from transitional regimes (e.g., climate change, technology and infrastructure design and construction) and cultural regimes (e.g., water as “human right” must be economically free)

  • Traditional definitions fail (e.g., factory beef from stem cells as “water technology”)

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Water as Earth System

  • Like all critical earth systems, it can be weaponized (cf: food as weapon in Darfur)

  • It is provided, traded, and sold both as a material (“water”) and as embedded in other products (“virtual water”)

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Embedded Water Content of Selected Items

Based on Gradel and Allenby, Industrial Ecology and Sustainable Engineering, 2010, Prentice-Hall; A.Y. Hoekstra and A.K. Chapagain, Water footprints of nations: Water use by people as a function of their consumption pattern, Water Resources Management, 21, 35–48, 2007

Product Embedded water content (liters)
1 microchip (2 g) 32
1 sheet of A4-size paper (80 g/m2) 10
1 slice of bread (30 g) 40
1 potato (100 g) 25
1 cup of coffee (125 ml) 140
1 bag of potato crisps (190 g) 185
1 hamburger (150 g) 2,400
Embedded Water Content, liters per gram
16
.125 (liters/m2)
1.33
.25
1.12 (l/ml)
.97
16

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Embedded Water

  • 80% of embedded water in global trade is in agricultural goods
  • ¾ in crops
  • ¼ in animal products
  • But beef is single largest component of virtual water flow at 13% of global VW, compared with 11% for soybeans and 9% for wheat, because . . .
  • To produce:
  • 1 ton of vegetables requires about 1,000 cubic meters of water
  • 1 ton of wheat requires about 1,450 cubic meters
  • 1 ton of beef requires 42,500 cubic meters

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Water as Earth System

WATER SYSTEMS

Production Technologies

Nitrogen Cycle

Carbon Cycle

Phosphorous Cycle

Biodiversity

Recycling Technologies

Treatment Technologies

Efficient Use Options

Agriculture

Global Trade

WATER ECONOMICS

Culture/Law

OTHER TECHNOLOGY SYSTEMS

EARTH SYSTEMS

USUAL

FOCUS

OF

WATER

POLICY

Human Health

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Institutional Time/Population Space
(log/log scales)

0

3

-1

1

2

-1

-2

Time

1

10

5

15

20

Small Group or Individual Decisions

Policy, Contract

Law

Constitution

Culture

Religion-Technology Systems (coupled vs uncoupled)

Traditions and Values

Fads

Population Involved

Source: Based on L.H. Gunderson, C. S. Holling, and S. S. Light, “Barriers broken and bridges built”, in L. H. Gunderson, C.S. Holling, and S. S. Light, eds., Barriers and Bridges (New York, Columbia University Press: 1995), p. 521

Human Psychology and Natural Systems Scale

102

104

106

108

1010

1012

10-1

100

101

102

103

104

105

106

107

108

1 hour

1 day

1 month

1 year

1 century

1 millennium

Wind Velocity

Human Transportation

Person

House

Livermore

United States

Circ of earth

Personal garbage

Tornados

The Tides

Thunderstorms

Dump

Faults

Aquifers

Ponds, Lakes

Storms

Jet streams

Meters

Seconds

Human psychological horizon

System Structure Over Different Time Scales

Time Scale

Endogenous

Exogenous

Principal Implementation Mechanism

Principal R&D Component

Integration of Natural and Artifactual Systems

Short Term (ca. 5 years)

Medium Term (ca. 5-10 years)

Long Term (ca. 10-100 years)

Incremental technology evolution within existing major technology systems

Evolution of product and process technology systems, marginal cultural change

Significant evolution of major technology systems; link between quality of life and material consumption; population levels; most aspects of culture

Population level, cultural change

Population level, significant cultural change

Almost nothing

Policy

Changes in legal structures, disciplinary assumptions, based on industrial ecology

Metrics, changes in fundamental conservative cultural systems (e.g., religion)

Short term industrial ecology R&D (e.g., Design for Environment, Integrated Pest Management)

Industrial ecology infrastructure (e.g., environmentally preferable materials database)

Industrial ecology systems (e.g., resource and energy maps of communities and regions)

Experimental stage involving small systems (e.g., bioreactors, drug production in genetically engineered sheep)

Partial integration of biological and engineered systems (e.g., commercial energy from biomass; engineered wetlands for flood, pollution control, and waste processing)

Management of integrated regional and global systems (e.g., water cycles in Yellow River watershed or Southwestern United States); Earth Systems Engineering