Geoscience Reference
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Conceptual model of the adaptive cycle, illustrating how a system, subjected to forcing, develops through
two principal phases: r and K. Passing a tipping point may result in the system facing a destruction phase
Ω before it renews itself, if the forcing decreases, in the α phase.
Reproduced from Wassmann and Lenton (
2012
), which was redrawn from Gunderson and Holling
However, when tipping points are also points of no return (e.g. bifurcation points), more
complex dynamics can emerge (
Figure 5.2
)
. When a point of no return is reached (even if
forcing is reduced or ceases) the system will enter the destruction phase Ω and then switch
to a new state or regime with its own dynamics. This new regime can then develop around
its own adaptive cycle, which may also reach a different point of no return (second bifurc-
ation point) and, theoretically, switch the system back to the original regime or on to yet
another new one.
Figure 5.2
Altered conceptual model of adaptive cycles where the tipping point is now a point of no return. The ori-
ginal regime (lower half of the figure) can switch over to a new regime (upper half), or the system can
stay within the original regime as in
Figure 5.1
. There can exist a multitude of regimes with potential
switches between them. Here we only display two to illustrate the basic principle.
Reproduced from Wassmann and Lenton (
2012
).
To apply the panarchy frameworks to ecosystem changes in the Arctic Ocean, we consider
a series of spatio-temporal scales or domains individually and through the relationships
among them. Here it is important to keep in mind that the complex-adaptive system model
is meant to capture the interacting state variables and relationships among them at a giv-
en (focal) scale, and not simply all possible variables occurring at that scale. The system
changes as a result of both of these internal interactions and its external drivers. A resili-
ent ecosystem, then, exhibits relatively stable functional relationships andfeedbacks within
and across scales, whereas ecosystem instability (regime shift) involves the alteration of
