1. Comments: Emergent Properties of Human-Environment Systems
Jim Heffernan
Florida International University
Sustainability Science DGS
1 Nov 2010

2. Questions from the Chapter
1. What are emergent properties of complex human-environment systems? Are there important differences between the way we should characterize the human and environment systems?
2. What are resilience and vulnerability? What is the relationship between them? How are they treated differently in the social and ecological sciences?
3. What are the sustainability implications of tipping points?
Management of ecosystem services
Assessment of sustainability

3. Resilience and Vulnerability as Emergent Properties
Vulnerability: likelihood of suffering harm from exposure to hazard or disturbance
Applied to humans (individuals, communities, etc.)
Resilience: capacity to withstand or adapt to change
Originally applied to ecosystems in relation to tipping points
Also used in a more general sense, especially with respect to socio-ecological systems
Inverse or converse of vulnerability?

4. Vulnerability and Resilience
Exposure * Sensitivity/Resilience
Chapter 3.1

5. Vulnerability, Resilience, and Sustainability
Vulnerability = likelihood of suffering harm =
Exposure * Sensitivity/Resilience
Relation to sustainability is unclear
Vulnerability as costs incurred by disturbance does not preclude sustainability
Resilience as mitigator of vulnerability
Normative view of resilience as a good thing
Glosses over non-linearity that is at the heart of resilience concept

6. Resilience of Ecosystems
Resilience defined as size of disturbance that can be withstood without collapse of system state
Baseline is stability (= absence of change).
Undesirable state is also resilient!
Carpenter et al. 2001

7. Vulnerability and Resilience – an alternative view
Exposure * Sensitivity
Sustainability =
Resilience / Vulnerability
Carpenter et al. 2001

8. Resilience of Human-Environment Systems
Adaptive Cycle model integrates resilience with change – not all of which is bad!
‘Panarchy’ links adaptive cycles at different scales
Local system resilience to external events
Global system resilience to internal shocks
Implications for sustainability at local vs. global scales
Holling 2001

9. Emergent behavior in a CHES
Peterson et al. 2003

10. Emergent behavior in a CHES
Peterson et al. 2003

11. Emergent Behavior in CHES
Management based on optimal yield rather than maintenance of resilience generates cyclical transitions between states
Ignoring tipping points incurs uncounted costs
Disturbance that is external to ecosystem is internal to coupled human-environment system
Peterson et al. 2003

12. Detecting Tipping Points
Near tipping points, many systems exhibit changes in spatial/temporal variance and/or autocorrelation
Technical challenge: selecting appropriate variables and metrics (variance vs. auto-correlation)
Implementation challenge: Developing management institutions with capacity to respond to indicators