Taking out the trash. The need to urgently reduce emissions to avoid triggering ‘tipping points’ that could see Earth putting us out as the trash
New Zealand Climate Crisis: Blog 10
[4200 words - a 20 minute read, (Summary 700 words - a 3 minute read)]
1. SUMMARY
For most of us, putting out the rubbish is a weekly or fortnightly chore. The trash is often taken away by a service provider and dumped in a landfill where it disappears from our consciousness and, if organic in origin, generally eventually decomposes anaerobically, yielding two greenhouse gases – carbon dioxide and methane.
These gases – in quantities that vastly exceed the amounts produced from the decomposition of our trash – are also produced by human activities that include industrialised scale farming/land use change and the burning of fossil fuels (coal, oil and gas), actions that are amongst the hallmarks of modern industrialised societies.
The continuous build-up of these, and some other greenhouse gases, in the atmosphere since the Industrial Revolution, has resulted in the case of carbon dioxide, of an atmospheric concentration now exceeding 420 ppm, a level last seen around 15 million years ago and it continues to increase.
The additional global heating that results is driving the current climate change process (or, more accurately, considering the situation that we now face, climate crisis) that is running. This has begun to jeopardise the heretofore stable conditions under which the modern human race has developed and thrived, the impacts of which will hugely affect our lives – and not in a good way - for the foreseeable future.
As bad as this situation is, if we do not urgently act to reduce emissions at a much faster rate than we are currently doing, the situation is going to get a lot worse in future.
This because the five interactive components (or domains) that collectively comprise the climate environment[1] have been remarkably resilient to, and forgiving of, our transgressions to date but this may be about to change.
Scientists have identified more than 25 ‘tipping points’ (i.e. breaking points) in different climate component systems, which when triggered (eg by continued global heating), will see systems undergo a large, rapid, and often irreversible shift to a new state.
Tipping points that operate at local, regional or global levels have been identified and they interact to varying degrees, across space and time, and most of these interactions are destabilising.
There is some good news in that the impacts from triggering tipping points will play out, in human terms, over extraordinarily long time frames; decades to centuries or even longer. More importantly though, once triggered, the tipping process is likely to be irreversible and so not able to be stopped by anything we or our descendants subsequently do.
What triggering tipping points do then, is to limit the options (i.e. choices) that we and especially our children, grand-children and their descendants will be able to make about their environment and how they live. Our prior actions may, by reaching tipping point thresholds, have pre-determined many of the environmental settings (e.g. frequent flooding, and or droughts, very high temperatures) that will hugely constrain how they and their communities are able to live out their lives.
As a worst case scenario, if, despite knowing the possible consequences, should we be uncaring and greedy enough to trigger global scale tipping points we may bequeath to them a world in which where many parts (or even the entirety) of the planet will become uninhabitable.
If so, the consequences (or cosmic justice) are that the Earth could, in effect, take out the trash - us humans - and we will be disposed of in the same way we currently take out our rubbish. There will be nothing personal in this situation, any more than there is when we dispose of our household rubbish, but our failure to avoid triggering tipping points may set unstoppable and irreversible changes in motion, with potentially catastrophic effects on us and, in particular, our descendants.
KEY POINT #1: We must act, much more urgently than we currently do, to address climate change and its impacts to rectify the situation while we are still able to do so. The issue is that our inadequate actions to date have meant that that we are moving ever closer to the “tipping points” – thresholds at which potentially irreversible, catastrophic and self-sustaining climate changes occur.
2. BACKGROUND: HOW HAS THIS DIRE SITUATION COME ABOUT?
2.1 The root cause of the problem – human generated ‘greenhouse gases’
The current situation has arisen as a consequence of humans continuing, over the last three hundred years or so – from the start of the industrial revolution - to undertake large-scale land use changes and to extract and burn increasing levels of fossil fuels (initially coal, then oil and gas) for industrial, commercial and personal use, the latter including the use of diesel or petrol fuelled motor vehicles. Such activities, as well as providing energy, generate chemicals called “greenhouse gases” (including the aforementioned carbon dioxide and methane) as combustion products.
2.2 The physical problem – increased levels of “greenhouse gases” are heating up the Earth’s oceans and land areas
With increased carbon dioxide in particular staying in the atmosphere for hundreds of years or longer, the concentrations of these chemicals have built up. A property of these chemicals in the atmosphere is that they trap (and reflect back to the Earth’s surface) more of the heat from the sun – itself vital to keeping the Earth at a habitable temperature - that would otherwise be re-radiated back to space in quantities and which (absent the climate change process) would otherwise keep the Earth’s surface at a temperate 13 – 17C.
This heat imbalance has caused the long-term average global temperature to rise – by between1.2C to 1.4C since the late 1800’s and it is still increasing. [The carbon dioxide concentration driver of the had not exceeded 300 ppm for some two and a half million years before the start of the industrial revolution. Today it is >420 ppm, a 50% increase.] Worse, as the level of greenhouse gases increases, so the rate of warming also continues to increase; from 0.06C per decade since 1850, to more than three times that (0.2C per decade since 1982). The ten warmest years in the 175-year record have all occurred during the last decade (2015–2024) and the last two years have seen the largest temperature increase in history.
For context, the closest historical comparator we have, from the geological record, about how our current precarious situation may unfold, is the Pliocene era (~3 million years ago). During this time, the global temperature was 3C hotter than pre-industrial times and the sea level was many meters higher than it is today. It is hugely relevant that this temperature spike in the Pliocene era took thousands of years to happen, whereas we are half-way to that level of global temperature increase in only 150 years.
KEY POINT #2: The planetary heating that is happening is disrupting the multiple, interconnected systems that would – absent this heating and ignoring other adverse environmental impacts (e.g. chemical pollution) - otherwise maintain our environment in a condition that is conducive to the human race, and the myriad other species that share the planet with us, thriving.
3. THE IMPACTS FROM THE INCREASED LEVELS OF GHG WE HAVE PUT INTO THE ATMOSPHERE WILL BE WIDESPREAD
The heating that is happening has many consequential effects. These have been laid out in detail in reports by many organisations and researchers including the United Nations body that assesses – and regularly updates - the science related to climate change and its impacts; the Intergovernmental Panel on Climate Change (IPCC)[2].
More generally, climate change is already (and will increasingly have more severe) impacts both directly – on the physical environment in which we live - and indirectly – on us as a species and our societies that will affect viability of many of our communities:[3]
The former include
§ Extreme Weather: More frequent and intense heatwaves, vegetation fires heavy rainfall, flooding, landslides, droughts, and stronger storms (cyclones).
§ Ice & Sea Level changes: Rapid melting of glaciers and ice sheets, shrinking Arctic sea ice, leading to significant sea-level rise.
§ Ocean changes: Warmer ocean waters fuel storms and harm marine life; increasing ocean acidity stresses shell-building organisms like plankton and corals impacting the food chain.
§ Ecosystem Disruption: Species migrating unpredictably, loss of habitats and threats to biodiversity.
The latter include:
§ Health: Increased heat stress, heatstroke, asthma, and spread of insect-borne diseases (like dengue).
§ Infrastructure: Flooding damages roads and systems; increased need for air conditioning in summer.
§ Water and Food: Strains on freshwater supplies, impacts on crop yields, and threats to food security.
§ Economic Costs: Higher maintenance for infrastructure, potential energy cost shifts (less winter heating, more summer cooling).
§ The social costs and impacts of large-scale, climate driven migration.
It is essential to understand also that (1) many of the impacts are interconnected and cascade through the different pathways and systems that are affected and (2) the rapid pace of change means that the issue is a climate crisis rather than a climate change and urgent action is imperative.
This article will focus on the increased danger for us as our collective complacency - and failure to take climate change seriously enough - means that the risks of environmental ‘tipping points’ being triggered continues to increase.
KEY POINT #3: The impacts that climate change are bringing will affect many aspects of our lives including our health, our food production, loss of the many iconic native flora and fauna species that we treasure and, for many of us, the things we take for granted as we live our lives – the security of our homes and as a consequence of more frequent extreme weather events (and the infrastructure damage that this will cause) our ability to easily travel around the community for work and leisure.
4. AN INTRODUCTION TO TIPPING POINTS
4.1 The Earth’s climate system has five major components:
Unsurprisingly, the Earth's climate system is complex with five interacting components (“domains”) operating at a global scale: the atmosphere (air), the hydrosphere (water), the cryosphere (ice and permafrost), the lithosphere (earth's upper rocky layer), and the biosphere (living things).
A large number of processes operate within and between these domains with energy, water and elements (such as carbon) exchanged. To make things even more complicated, collectively these transfers take place over time frames that vary hugely:
§ From the nearly instantaneous to hours and weeks (e.g.):
o Heat transfer through the movement of air masses in the atmosphere (convection and advection) influences daily weather patterns.
o Plants and animals exchange CO2 with the atmosphere through photosynthesis and respiration.
§ Years to decades to centuries (e.g.):
o The burning of fossil fuels has significantly increased atmospheric CO2 concentrations since the 19th century.
o Carbon is stored in wood and soils for an intermediate term of 20- several hundred years.
o Global average surface air temperature responds to radiative forcing over a period of decades. The maximum climate effect of methane emissions, which last about a decade in the atmosphere, occurs about 20 years after emission.
§ Centuries to millennia (e.g.):
o The ocean surface and atmosphere gradually exchange CO2 while mixing with deep ocean waters.
§ Up to hundreds of millions of years (e.g.):
o Geological processes like weathering and volcanism affect the carbon cycle and climate over millions of years.
To reiterate, the climate system has a substantial number of moving parts, making their study, and the identification of critical parameters (such as tipping points) and the processes that they impact, a complex one.
4.2 Climate system modelling
Our understanding of tipping points (and if and how our continued emission of GHG can trigger them) arises from mathematical modelling of the Earth’s climate system processes and future impacts.
To help us understand the climate system, scientists use models [“Earth System Models,” (ESM’s)] that are complex simulations, performed by super-computers for 3-D grid areas that represent parts of the Earth. They mathematically model the atmosphere, oceans, land, and ice, incorporating physical, chemical, and biological processes to understand past climate shifts and project future changes.
This work is combined with Earth Observation [EO] information - the systematic gathering and analysis of information about Earth's physical, chemical, and biological systems using remote sensing (satellites, aircraft, drones) or ground-based sensors - for helping understand climate change.
To make this process more challenging, the behaviour of a complex system, such as the climate, is intrinsically difficult to model due to the dependencies, competitions, relationships, and other types of interactions between their parts or between a given system and its environment. Complex systems have distinct properties that arise from these relationships, such as feedback loops – e.g. warmer air holds more water vapor, which itself is a greenhouse gas, trapping more heat and causing more evaporation – and, of particular interest here, tipping points.
4.3 What are “tipping points”?
A tipping point is a critical threshold which if exceeded, can cause a system to undergo a large, rapid, and often irreversible shift to a new state.
Several types of tipping points have been identified[4]]:
§ Bifurcation tipping occurs when a system becomes unstable as conditions slowly change, leading to a sudden transition once a critical threshold is crossed.
§ Noise-induced tipping results from random fluctuations or extreme events pushing a system past its tipping point despite otherwise stable average conditions.
§ Rate-induced tipping happens when the rate of change exceeds the system’s ability to adapt, even before reaching absolute thresholds.
In the context of climate change, tipping points are critical thresholds in Earth's major climate drivers (such as ice sheets, rainforests, oceans) where a small extra shove from global warming triggers abrupt, self-amplifying, and often (in human timeline terms) irreversible, shifts to entirely new states such as the melting of an ice-sheet, potentially with huge consequences for us and our fellow earth-dwelling species. As bad as this would be the consequences will be even worse if the existence of the new state triggers other tipping points in the climate system.
As an analogy, consider the act of leaning back in the chair you are sitting in. If you lean back a little, all four of the chair legs stay on the ground. Lean back a little more and the front legs leave the ground, but as soon as you stop leaning back they return to the ground, so not a problem. You keep leaning back a little more each time, with the same result. At some point though, if you keep on leaning further back, a tipping point – the point of no return - will be reached; the chair will tip backwards, it will not be possible to stop or reverse the fall and a new state (you and the chair on the floor) will have been reached.
In the above example the tipping point is straightforward – it is when the centre of mass (roughly where your belly button is when seated) moves beyond the pivot point (the imaginary line joining the back legs of the chair) meaning gravity's pull[5]
In the climate change space, the situation is much more complicated, but the result is the same – a small (e.g. temperature) change causes a system to undergo a large, rapid, and often irreversible shift to a new state.
Scientists are working to identify climate drivers, understand their triggers (e.g., specific temperature rises, the scale and location of deforestation), model cascading impacts, and warn policymakers about the risks that are emerging as the continued warming we are generating is pushing some systems close to tipping. [At least one may already have been exceeded – see below.]
KEY POINT #4: If you fall backwards by leaning too far back on your chair you will potentially injure yourself – and, if anyone else is around, look like a dickhead. If climate change tipping point thresholds are exceeded because we don’t care enough to do take the actions – urgently reduce emissions - necessary to avert them, then the continued existence of many of our communities, large and small, is at threat from catastrophic self-sustaining climate breakdown.
If this happens it will be the first time in the four billion-year history of the world that the planet’s dominant species has knowingly and deliberately put itself in the planetary trash bin, clearing the way for a new apex predator species to emerge from the rubble.
5. SOME TIPPING POINTS AND THEIR CURRENT STATUS
5.1 The contemporary understanding of tipping points with “Earth system” i.e. global impacts
One of the most authoritative publications on tipping points is the “Global Tipping Points Report” [see Footnote #4] that is published annually, the latest being on September last year. This report includes information on Earth system tipping points; the risks, system governance, positive tipping points and some case studies [6],[7],[8].
The five systems that are thought to be closest to tipping under current global heating conditions are listed in Appendix 1 below [From Table 2.2.2, Footnote # 3 and from Footnotes 6 and 7]:
5.2 Interaction between tipping systems
Importantly, tipping points and systems do not exist in isolation but interact, to varying degrees, across space and time. Interactions may be:
§ Stabilising: e.g. weakening (or tipping) AMOC[9] leads to cooler temperatures around Greenland, which may be strong enough to slow down (or even stop) further GrIS melt.
§ Destabilising: e.g. The linkage between GrIS and the AMOC, where meltwater from the GrIS destabilises the AMOC.
§ A combination of both of the above effects.
A recent paper notes that while “ … Many feedback loops significantly increase warming due to greenhouse gas emissions. However not all of these feedbacks are fully accounted for in climate models” so “ … an accelerated reduction of emissions are needed to minimize risks.”[10]
Key things to note about tipping points:
§ We are quickly approaching global warming thresholds where tipping system interactions become relevant, because multiple individual thresholds are being crossed. These are at levels of 1.5 - 2.0°C of global warming.
§ The majority of interactions between climate tipping systems are destabilising.
§ The AMOC is the global mediator of tipping point interactions. It features in 45 per cent of all assessed tipping point interactions.
6. THE NEED TO TAKE ACTION AND URGENTLY REDUCE EMISSIONS TO AVOID CROSSING TIPPING POINT THRESHOLDS AND BECOME THE PLANET’S TRASH
Climate tipping points do not present an immediate, or even medium-term, threat to either life or limb in New Zealand, though the consequential indirect impacts – on matters such as trade and international relations - of the die-off of tropical coral reefs (where it is highly probable that the tipping point has already been crossed [see Table 1]) should not be underestimated.
The nature of the climate change - or more accurately, the climate crisis – process we humans have set in motion is well known, as are the various impacts it is already having (and increasingly will have) on our lives and the lives of our children, grand-children and their descendants.
Taking action to address the challenges climate change poses to us and our communities has proven difficult for a number of reasons, including the fact that it is a ‘long-problem’ (where the causes and effects span more than a generation) and that its impacts will play out over decades to centuries and longer. These timeframes are at least generational (20 – 30 years) and extend well past the human lifespan of less than 100 years.
For these and other reasons, a disconnect exists between the imperative to take urgent action to reduce emissions (and the costs and discomforts that often accompany such measures) and experiencing the benefits arising from the actions taken. The outcome is often that needed actions are ignored or deferred, especially when economic conditions are difficult – something is, of necessity, front of mind for many people.
We have also known about the existence of climate change tipping points (and, increasingly, about their inter-connections and linkages) and the consequences of ignoring them, for some years now.
Failure to act on the knowledge, and need for action, relating to tipping points will however, have much more severe consequences than deferring action on what is, albeit erroneously, perceived simply as the generic ’ long-problem’ that is climate change.
At one level the difference is academic; whether to minimise future adverse impacts in general (and reduce the cost and difficulty of adapting to the already locked-in impacts), or to avoid triggering specific tipping points, the common solution is to urgently reduce the levels of GHG in the atmosphere. In reality, and considering the issue through an outcome lens, our options are more nuanced than this.
In the absence of any tipping points, the climate’s response to GHG emission levels will be a proportionate one; the higher the level of emissions the more severe the impacts. Most importantly though, the climate change impacts would be reversible, over (albeit potentially very) long time frames. More specifically, if we reduced the level of GHG in the atmosphere, this would, eventually, restore the state of the five domains (atmosphere, hydrosphere, cryosphere, lithosphere and biosphere) to the benign, indeed essential, conditions that existed prior to the Industrial Revolution.
This is not to say however, that all the physical and social impacts on us and our communities that will have occurred in the interim will be reversible, but it will deliver an environment in which our descendants, and the myriad of other species that share our world, can once again thrive.
Unfortunately, this is not how the world operates; tipping points do exist and we ignore them at our peril. We have created the conditions that have almost certainly triggered at least one important tipping point (the tropical coral reef die-off) and we not far from triggering others.
Tipping points are – or should be - a game changer for how we view our environment and the damage we are doing to it because triggering them because:
1. The system affected changes to a new state that that will not be beneficial in its impacts on us, our communities and/or the other species on which our life depends
2. The change is irreversible in terms of human lifetimes.
3. Tipping points do not exist in isolation but are linked to other tipping points
If we fail to understand the vital importance of tipping points and reign in our emissions at a rate sufficient to avoid reaching any (more) tipping point thresholds, then we limit, to some extent, not only our future options, but those of our children, our grand-children and their descendants. Depending on the nature and impact of the tipping points that we ignore, we may be relatively lucky and exacerbate the climate crisis impacts on our communities to only a small degree.
If however, we continue to recklessly – and knowingly - ignore the impacts of our planet polluting actions and the existence climate tipping points that are a consequence, then we (or more accurately our descendants) will suffer the consequences which, at worst, will see humans (or at least anything that resembles current human society) removed from the crew list of a future Planet Earth as it continues its journey through the solar system – we will have been put out with the global trash by the environment that we have ourselves trashed.
On the positive side, if this dire situation does come to pass, and we are reviled and hated by future generations for our ignorance, recklessness and stupidity in allowing this situation to come to pass, be reassured that this disgust and opprobrium will only be temporary and that, sooner (or later) there will be no-one around to remember just how selfish we were.
7. CONCLUSIONS
Looking out the window as I write this, the sun is shining and it is a lovely, warm summer’s day. It is a big ask therefore to expect people to think about (and, more importantly, to take any actions we can to avert) the impacts that climate crisis that we are facing will visit on us and especially our descendants, - but this is what is now urgently needed.
It is true that, any actions we as individuals can take will not move the global ‘climate change dial’ but it is equally true that the solution lies in our collective hands.
Our actions over generations, have carelessly and, worse, knowingly, damaged the climate systems that keep our environment in a state that favours both us and the other species that we humans share Earth with, depend on.
These climate systems are simply responding, according to the laws of physics and chemistry, to the circumstances that we have created. The Earth no more needs us than, as articulated by feminist’s in the 1970’s, a fish needs a bicycle.
We have, so far, chosen not to act to adequately address the problem and we have the option of continuing along this path. If we do so however, there is a very high chance that we are consigning our descendants to be the planet’s future trash (compost?).
APPENDIX 1: Five systems closest to – or which have already reached – tipping points
1. Greenland ice sheet [GrIS] disintegration: Likely Tipping Point reached at 0.8 – 3.4C global warming
Part of the Cryosphere, the GrIS is the second largest ice sheet in the world,. Covering 1.7 million km2. It contains 10% of the frozen freshwater on Earth.
The impacts of this Tipping Point being reached include:
§ 7m sea level rise, submerging coastal areas
§ Increased freshwater runoff can weaken or collapse the Atlantic Meridional Overturning Circulation, impacting North Atlantic and European climate.
§ Affects atmospheric circulation, leading to warmer air over Greenland, altered European temperatures, and changes in weather patterns.
§ Destabilizes the jet stream, potentially causing more extreme weather events globally.
Comments:
The GrIS is losing ice rapidly, with modern melt rates far exceeding pre-industrial levels, and significant contributions to sea-level rise expected by 2100 (6-33cm depending on emissions). Full disintegration will take millennia.
2. West Antarctic Ice Sheet [WAIS] collapse: Likely Tipping Point reached at 0.5C
Part of the Cryosphere, the WAIS is an ice mass covering 2 million km2
Mostly grounded below sea level making it vulnerable to the warming ocean (than e.g. the much larger East Antarctica Ice Sheet [EAIS] is
The impacts of this Tipping Point being reached include
§ 3 - 4m of sea level rise
§ Fresh meltwater from WAIS also contributes to ocean stratification and dilutes the formation of salty Antarctic bottom water, which destabilizes the Southern Ocean overturning circulation'
Comments:
2,000 -13,000 years
Ice loss from the WAIS is accelerating, and some outlet glaciers are estimated to be close to or possibly already beyond the point of self-sustaining retreat.
3. Permafrost collapse: Likely Tipping Point reached at 1 - 4C global warming
Also part of the cryosphere, permafrost is ground that remains frozen for at least two consecutive years. It underlies about fourteen million km2 (15 per cent of the land surface area) in the Northern Hemisphere. Scientists believe there is nearly twice as much carbon in permafrost than is present in Earth's atmosphere.
The impacts of this Tipping Point being reached include:
§ Thawing would allow the preserved organic matter [~1000 Gt Carbon] to degrade and emit greenhouse gases in the process, primarily as CO2 but with a proportion as methane.
§ Simulations show that, while average annual permafrost carbon emissions of ~0.3–0.7 GtC/yr are insignificant compared to present-day fossil fuel emissions (~10 GtC/yr), permafrost thaw can still reduce the carbon budget by ~11–13 per cent by 2300 under 2°C or 3°C warming scenarios.
Comments:
Land-based permafrost thawing remains characterised by multiple regional-scale tipping processes rather than exhibiting a single global tipping threshold
4. Deep convection in the North Atlantic subpolar gyre [SPG]: Likely Tipping Point reached at 1 - 4C global warming
The SPG is part of the Ocean and atmosphere circulations. It is a circular ocean current, across the North Atlantic from the Intertropical Convergence Zone (calms or doldrums) to the part south of Iceland, and from the east coasts of North America to the west coasts Europe and Africa.
Proxy records provide empirical evidence that the SPG crossed a tipping point during the transition into the Little Ice Age, with early warning signals appearing before the abrupt SPG weakening in the 14th century. A recent paper suggests that the SPG region may now be moving towards a tipping point.
The impacts of this Tipping Point being reached include:
§ An SPG collapse would impact European weather, precipitation regime, and climate with strong impacts on fisheries and biodiversity and therefore wide societal implications
§ A transition between two SPG stable states has been suggested to explain the onset of the so-called “Little Ice Age” in which colder conditions prevailed in Europe during the 16th–19th centuries
Comments:
Years to decades
5. Tropical coral reef die-off: Likely Tipping Point reached at 1 - 1.5C global warming
Part of the biosphere, these reefs are are complex ecosystems built around the symbiotic relationship of reef-building corals and photosynthetic algae. Increasingly though, global warming means warm-water coral reefs are experiencing ‘coral bleaching’ events, during which sustained marine heatwaves triggers corals to expel their symbiotic algae due to heat stress with the result that the reefs slowly die.
The impacts of this Tipping Point being reached include:
Around 500 million people around the world depend on coral reefs for food, income, tourism, and coastal protection.
Comments:
The tipping point threshold – with localised to regional level impacts - is likely to have already been reached
FOOTNOTES:
[1] The atmosphere (air), the hydrosphere (water), the cryosphere (ice and permafrost), the lithosphere (earth's upper rocky layer) and the biosphere (living things).
[2] IPCC Sixth Assessment Report, Working Group II “Impacts, Adaptation and Vulnerability”, 2022, https://www.ipcc.ch/report/sixth-assessment-report-working-group-ii/
[3] https://www.google.com/search?q=climate+change+impacts&oq=climate+c&gs_lcrp=EgZjaHJvbWUqBggDEEUYOzIGCAAQRRg5MgwIARAjGCcYgAQYigUyDAgCECMYJxiABBiKBTIGCAMQRRg7MgcIBBAAGIAEMgcIBRAAGIAEMgcIBhAAGIAEMgcIBxAAGIAEMgcICBAAGIAEMgcICRAAGI8C0gEJNjgyNGowajE1qAIIsAIB8QUnWwkE70bjYA&sourceid=chrome&ie=UTF-8
[4] Lenton TM et al “The Global Tipping Points Report 2025” University of Exeter, Exeter, UK. https://global-tipping-points.org/
[5] For more information on this see (e.g.) https://www.dailymail.co.uk/sciencetech/article-4520556/The-science-fall-chair.html
[6] See Footnote #3
[7] Wikipedia, “Tipping points in the climate system”, https://en.wikipedia.org/wiki/Tipping_points_in_the_climate_system#:~:text=the%20Amazon%20rainforest.-,As%20of%20September%202022%2C%20nine%20global%20core%20tipping%20elements%20and,50
[8] Loriani S et al, “Tipping points in ocean and atmosphere circulations”, Earth System Dynamics, Volume 16, issue 5, 1611–1653, 2025. https://doi.org/10.5194/esd-16-1611-2025.
[9] AMOC: Atlantic Meridional Overturning Circulation, is a crucial system of Atlantic Ocean currents acting as Earth's "conveyor belt," transporting warm tropical water north and cold deep water south, vital for global heat distribution but it's weakening due to climate change (melting ice adding freshwater),
[10] Ripple W J et al., “Many risky feedback loops amplify the need for climate action”, One Earth 6, February 17, 2023. Pp 86 - 91 https://doi.org/10.1016/j.oneear.2023.01.00
