Climate Change Tipping points and the Society
What are really, are these tipping points, in relation ot the Earth's systems and the society🤔? Let's talk, realise and live as climate change, potential of change.
With great thanks to the University of Exeter, having been one of their learners, under Prof. Tim Lenton, so is the background of my sharing of these topics on TIPPING POINTS in Climate change and the society.
Before we begin learning the nuts and bolts of tipping points, let’s clear up a few definitions that might come in handy.
Term Definition
Feedback : When a change in a system has consequences that ultimately add to or counteract the initial change.
Forcing A steady pressure on a system that changes its state.
Perturbation : A one-off nudge that moves a system from its initial state.
Stable state : A state to which a system recovers under some range of perturbations.
System : An interconnected network of ‘things’ - parts and processes connecting them - that together make up a coherent larger ‘whole’.
Tipping point : A point at which a small perturbation can cause a large change to a system – such as it entering a new stable state.
Threshold : Another term used for a point at which something dramatic happens to a system.
FEEDBACKS
Feedbacks, and in particular positive feedbacks, are a necessary ingredient for a system to undergo a tipping point change. Positive feedbacks are self-amplifying. This means that a small perturbation has a magnifying effect on the system.
A good example of this is the ice-albedo feedback.
Sea-ice only absorbs around 10% of the solar radiation that reaches it, whereas open ocean absorbs around 70% because the surface is darker. As global warming begins to melt sea-ice in the Arctic, more dark ocean is exposed and a greater proportion of the sun’s solar energy striking the area is absorbed. This warms the area further, leading to a shrinking sea-ice extent, which creates more space for dark ocean to absorb radiation… and so on.
Ice-albedo feedback The ice-albedo feedback in a nutshell. Open ocean gets warmer as more of it is exposed, leading to shrinking Arctic sea-ice.
Usually even positive feedbacks are constrained and a system will come to rest without a radical change in state. But sometimes the self-amplifying effect is so strong that the change runs away with itself - and a new state is created. That’s a tipping point. The crucial thing to understand is that for a system to undergo a tipping point there must be a strong positive feedback within its dynamics.
Over the Tipping Point
If a system with tipping points is subject to steady forcing this may push it towards one of those tipping points. A major concern is that human activities could push parts of the Earth’s climate system past tipping points. These tipping points don’t have to affect the whole Earth system, they can be contained within a sub-system like an ice sheet. However, the interconnections between parts of a system as large and complex as the Earth mean that a tipping point in one part can have knock-on effects for the other parts.
There is an important, if subtle, distinction between a tipping point and a point of no return. Some tipping points are also points of no return, because their consequences are hard or impossible to reverse - the loss of an ice sheet is a good example. But other tipping points are reversible - such as the loss of sea-ice described above.
The processes that trigger a tipping point, and the system it happens in, can be far more complex than the simple balance point and mechanical falling process of the chair in the last video. Tipping points in global warming could be almost invisible and set in motion long before we know they’re even happening. In fact, we could have already passed a tipping point without knowing.
Russell Glacier, Greenland. The satellite image is split approximately in half, with the left hand side showing the proglacial area in front of the glacier and the right hand side showing the west side of the Greenland ice sheet. There are around 100 blue ponds lining the ice sheet. Russell Glacier, Greenland. Melt ponds to the right of the picture on the ice sheet could indicate increased drainage and velocity of the ice. This could trigger the glacier, or ice sheet, to go beyond the point of no return. Image from Google and the US Geological Survey.
A NEW STABLE STATE
Passing a tipping point means that the system has moved to a new stable state. In some cases this can happen naturally, and it doesn’t always have to be a bad thing. In social systems, new stable states can indicate social progression – such as the acceptance of an opinion trickling throughout a population to eventually be intertwined in policy.
With great thanks to the University of Exeter, having been one of their learners, under Prof. Tim Lenton, so is the background of my sharing of these topics on TIPPING POINTS in Climate change and the society.
TIPPING POINTS
A tipping point is where a small perturbation can alter the future state of a system. In other words, when a small change leads to large and long-term consequences - a new stable state.Before we begin learning the nuts and bolts of tipping points, let’s clear up a few definitions that might come in handy.
Term Definition
Feedback : When a change in a system has consequences that ultimately add to or counteract the initial change.
Forcing A steady pressure on a system that changes its state.
Perturbation : A one-off nudge that moves a system from its initial state.
Stable state : A state to which a system recovers under some range of perturbations.
System : An interconnected network of ‘things’ - parts and processes connecting them - that together make up a coherent larger ‘whole’.
Tipping point : A point at which a small perturbation can cause a large change to a system – such as it entering a new stable state.
Threshold : Another term used for a point at which something dramatic happens to a system.
FEEDBACKS
Feedbacks, and in particular positive feedbacks, are a necessary ingredient for a system to undergo a tipping point change. Positive feedbacks are self-amplifying. This means that a small perturbation has a magnifying effect on the system.
A good example of this is the ice-albedo feedback.
Sea-ice only absorbs around 10% of the solar radiation that reaches it, whereas open ocean absorbs around 70% because the surface is darker. As global warming begins to melt sea-ice in the Arctic, more dark ocean is exposed and a greater proportion of the sun’s solar energy striking the area is absorbed. This warms the area further, leading to a shrinking sea-ice extent, which creates more space for dark ocean to absorb radiation… and so on.
Usually even positive feedbacks are constrained and a system will come to rest without a radical change in state. But sometimes the self-amplifying effect is so strong that the change runs away with itself - and a new state is created. That’s a tipping point. The crucial thing to understand is that for a system to undergo a tipping point there must be a strong positive feedback within its dynamics.
Over the Tipping Point
If a system with tipping points is subject to steady forcing this may push it towards one of those tipping points. A major concern is that human activities could push parts of the Earth’s climate system past tipping points. These tipping points don’t have to affect the whole Earth system, they can be contained within a sub-system like an ice sheet. However, the interconnections between parts of a system as large and complex as the Earth mean that a tipping point in one part can have knock-on effects for the other parts.
There is an important, if subtle, distinction between a tipping point and a point of no return. Some tipping points are also points of no return, because their consequences are hard or impossible to reverse - the loss of an ice sheet is a good example. But other tipping points are reversible - such as the loss of sea-ice described above.
The processes that trigger a tipping point, and the system it happens in, can be far more complex than the simple balance point and mechanical falling process of the chair in the last video. Tipping points in global warming could be almost invisible and set in motion long before we know they’re even happening. In fact, we could have already passed a tipping point without knowing.
A NEW STABLE STATE
Passing a tipping point means that the system has moved to a new stable state. In some cases this can happen naturally, and it doesn’t always have to be a bad thing. In social systems, new stable states can indicate social progression – such as the acceptance of an opinion trickling throughout a population to eventually be intertwined in policy.
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