Which System Variables Carry Robust Early Signs of Upcoming Phase Transition? An Ecological Example.
Growth of critical fluctuations prior to catastrophic state transition is generally regarded as a universal phenomenon, providing a valuable early warning signal in dynamical systems. Using an ecological fisheries model of three populations (juvenile prey J, adult prey A and predator P), a recent st...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2016-01-01
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| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC5025176?pdf=render |
| _version_ | 1811195824695148544 |
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| author | Ehsan Negahbani D Alistair Steyn-Ross Moira L Steyn-Ross Luis A Aguirre |
| author_facet | Ehsan Negahbani D Alistair Steyn-Ross Moira L Steyn-Ross Luis A Aguirre |
| author_sort | Ehsan Negahbani |
| collection | DOAJ |
| description | Growth of critical fluctuations prior to catastrophic state transition is generally regarded as a universal phenomenon, providing a valuable early warning signal in dynamical systems. Using an ecological fisheries model of three populations (juvenile prey J, adult prey A and predator P), a recent study has reported silent early warning signals obtained from P and A populations prior to saddle-node (SN) bifurcation, and thus concluded that early warning signals are not universal. By performing a full eigenvalue analysis of the same system we demonstrate that while J and P populations undergo SN bifurcation, A does not jump to a new state, so it is not expected to carry early warning signs. In contrast with the previous study, we capture a significant increase in the noise-induced fluctuations in the P population, but only on close approach to the bifurcation point; it is not clear why the P variance initially shows a decaying trend. Here we resolve this puzzle using observability measures from control theory. By computing the observability coefficient for the system from the recordings of each population considered one at a time, we are able to quantify their ability to describe changing internal dynamics. We demonstrate that precursor fluctuations are best observed using only the J variable, and also P variable if close to transition. Using observability analysis we are able to describe why a poorly observable variable (P) has poor forecasting capabilities although a full eigenvalue analysis shows that this variable undergoes a bifurcation. We conclude that observability analysis provides complementary information to identify the variables carrying early-warning signs about impending state transition. |
| first_indexed | 2024-04-12T00:50:13Z |
| format | Article |
| id | doaj.art-4d4689b4e06a4e8eaae46f47e6771e1b |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-04-12T00:50:13Z |
| publishDate | 2016-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-4d4689b4e06a4e8eaae46f47e6771e1b2022-12-22T03:54:46ZengPublic Library of Science (PLoS)PLoS ONE1932-62032016-01-01119e016300310.1371/journal.pone.0163003Which System Variables Carry Robust Early Signs of Upcoming Phase Transition? An Ecological Example.Ehsan NegahbaniD Alistair Steyn-RossMoira L Steyn-RossLuis A AguirreGrowth of critical fluctuations prior to catastrophic state transition is generally regarded as a universal phenomenon, providing a valuable early warning signal in dynamical systems. Using an ecological fisheries model of three populations (juvenile prey J, adult prey A and predator P), a recent study has reported silent early warning signals obtained from P and A populations prior to saddle-node (SN) bifurcation, and thus concluded that early warning signals are not universal. By performing a full eigenvalue analysis of the same system we demonstrate that while J and P populations undergo SN bifurcation, A does not jump to a new state, so it is not expected to carry early warning signs. In contrast with the previous study, we capture a significant increase in the noise-induced fluctuations in the P population, but only on close approach to the bifurcation point; it is not clear why the P variance initially shows a decaying trend. Here we resolve this puzzle using observability measures from control theory. By computing the observability coefficient for the system from the recordings of each population considered one at a time, we are able to quantify their ability to describe changing internal dynamics. We demonstrate that precursor fluctuations are best observed using only the J variable, and also P variable if close to transition. Using observability analysis we are able to describe why a poorly observable variable (P) has poor forecasting capabilities although a full eigenvalue analysis shows that this variable undergoes a bifurcation. We conclude that observability analysis provides complementary information to identify the variables carrying early-warning signs about impending state transition.http://europepmc.org/articles/PMC5025176?pdf=render |
| spellingShingle | Ehsan Negahbani D Alistair Steyn-Ross Moira L Steyn-Ross Luis A Aguirre Which System Variables Carry Robust Early Signs of Upcoming Phase Transition? An Ecological Example. PLoS ONE |
| title | Which System Variables Carry Robust Early Signs of Upcoming Phase Transition? An Ecological Example. |
| title_full | Which System Variables Carry Robust Early Signs of Upcoming Phase Transition? An Ecological Example. |
| title_fullStr | Which System Variables Carry Robust Early Signs of Upcoming Phase Transition? An Ecological Example. |
| title_full_unstemmed | Which System Variables Carry Robust Early Signs of Upcoming Phase Transition? An Ecological Example. |
| title_short | Which System Variables Carry Robust Early Signs of Upcoming Phase Transition? An Ecological Example. |
| title_sort | which system variables carry robust early signs of upcoming phase transition an ecological example |
| url | http://europepmc.org/articles/PMC5025176?pdf=render |
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