Amplifying Feedback
Nine feedback cycles driving global heating
Global heating is causing more global heating.
Here are nine “self-amplifying feedback cycles” driving this heating. These cycles are “self-reinforcing, circular chains of cause-and-effect”, like the “permafrost feedback cycle”.
The permafrost feedback
| Higher air temperatures | More melting of permafrost | |
| More greenhouse heating | More methane & CO2 in the air |
If this feedback dominated, we would see:
- higher air temperatures, causing
- more melting of permafrost (ice containing frozen plant & animal matter), causing
- more decay of thawing organic matter, releasing
- more carbon dioxide & methane into the atmosphere, causing
- more greenhouse heating, which closes the cycle by causing
- higher air temperatures.
This permafrost feedback alone could wreck our climate. Permafrost contains vast amounts of carbon, about 1.6 times more than is already in our atmosphere.
It’s concerning that measurements show increases in every element of this feedback:
- Global air temperatures are rising,
- Permafrost temperatures deep within measurement boreholes are increasing, showing that permafrost melting is also increasing. (This link was on the US EPA site: “https” followed by “://www.epa.gov/climate-indicators/climate-change-indicators-permafrost”)
- Atmospheric carbon dioxide is surging, and
- Atmospheric methane is soaring.
These increases show that the permafrost feedback is active and may already be self-sustaining and unstoppable. We cannot tell if it’s self-perpetuating now because it is supported by:
- human emissions of carbon dioxide and methane, &
- other feedback cycles, which are also increasing global temperatures. (I describe seven more of these feedback cycles on this page.)
Humans are playing with fire by continuing to fuel these feedback cycles, and the critical question is whether humans can stop this dangerous amplification of global heating.
For more information on methane, refer to the methane feedback cycle on this website.
The ice cover feedback
| Higher air temperatures |
| Less Ice Cover |
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| Less sunlight reflected & More absorption of sunlight |
This dynamic also threatens our climate. One thing in its favour is that it is reversible and could amplify cooling, if cooling occurred; see below.
See the dwindling Arctic sea ice on this website.
These causal linkages are tendencies.
The cause-and-effect linkages in these feedbacks are tendencies or likely outcomes. External events often disrupt the links in these feedback cycles, preventing the feedback from becoming dominant. For example, with “less ice cover”, the Arctic would normally “absorb more heat from the sun”; however, after a volcanic eruption, volcanic ash could reduce the sunlight reaching the Arctic, and the Arctic would NOT “absorb more heat”.
The water vapour feedback
| Higher air temperatures | (1) More evaporation & (2) Warmer air can hold more water vapour | |
| More greenhouse heating | More water vapour in the air |
If this feedback dominated, we would see:
- higher global air temperatures, leading to
- (1) more water evaporating from oceans, and (2) the air being able to hold more water vapour, causing
- more water vapour in the air, causing
- more greenhouse heating of the atmosphere, causing
- higher air temperatures.
This cycle is reversible, as global cooling would reduce atmospheric water vapour, but we are far from seeing any global cooling.
This feedback is also fast-moving as:
- Water vapour is a potent greenhouse gas,
- There is more water vapour in our atmosphere than any other greenhouse gas, and
- When you change the air temperature, you immediately change the amount of water vapour that the air can hold.
(Climate Change: Now or Never: New Scientist: 24 Apr 2021: page 37).
The phytoplankton feedback
| Higher air temperatures | More ocean surface heating | |
| More carbon dioxide in the air | Less nutrient up-welling | |
| Less photosynthesis & Less carbon sinking to the ocean floor | Reduced phytoplankton population |
See the heating of the ocean surface and the phytoplankton feedback cycle on this website.
The ocean CO2 feedback
| Higher temperatures | Higher ocean temperatures | |
| More CO2 in the atmosphere | Ocean can hold less CO2 |
See section “Ocean CO2 feedback” on the “Temperature & CO2” page on this site websites
The forest fire feedback
| Higher air temperatures | More heat & drought | |
| More carbon dioxide in the air | More forest fires |
See fires intensifying climate change on this website
The ice-darkening feedback
| Higher air temperatures | More melting of the ice sheet surface | |
| Less sunlight reflection | More dark matter on the ice surface |
If this feedback dominated, we would see:
- Higher global temperatures cause
- More ice sheet melting, which exposes
- More dark matter on the ice surface, like ash from distant bushfires that was buried in the glacier and is now on the ice surface, which causes
- The ice sheet to reflect less sunlight back into space, which closes the cycle by causing
- Higher global temperatures.
The glacier altitude feedback
| More glacial surface melting |
| A drop in the altitude of the glacier surface |
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| A rise in the average temperature at the glacier surface |
This feedback occurs because the average temperature at the top of a mountain is lower than at sea level. This is relevant because we have some deep ice sheets, such as those in Antarctica, which can reach depths of up to 4.9 kilometres.
See Glaciers in Retreat on this website.
The populist politics feedback
| Higher air temperatures | More extreme weather | |
| Less climate action | More conflict over land, water, food & housing | |
| More populist politics | More migration |
See the right-wing populism feedback cycle on this website.
Feedback that could limit global heating
The Arctic cooling feedback
The above “Arctic heating feedback” is reversible. It would become the “Arctic cooling feedback” and amplify cooling if cooling occurred.
| Lower air temperatures |
| More Ice Cover |
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| More sunlight reflected & Less absorption of sunlight |
The current exceptionally high levels of greenhouse gases in our atmosphere mean we are unlikely to experience any global cooling. Therefore, we are unlikely to see any amplification of global cooling.
Other global heating feedback cycles are also reversible, e.g., the water vapour feedback. Some feedback cycles are not reversible, e.g., the methane release feedback.
The amplification of climate action
Here is a feedback cycle that could amplify climate action in Australia and thereby help limit global heating.
 | More popularity for the superpower vision |  |
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| More benefits |  | More progress toward the vision |
In this feedback:
- the increasing popularity of the vision of “Australia as a renewable energy superpower” tends to
- increase progress towards that vision, which tends to
- increase the resulting benefits, which tends to close the cycle by
- further increasing the popularity of the superpower vision.
Focusing on the feedback cycles that amplify global heating can be demoralising. It can be more energising to focus on positives, like this “amplification of climate action feedback”, which could propel Australia towards an attractive future. For more on this, see:
- The amplifying feedback cycle of vision, progress & benefit on this website, and
- Australia’s progress towards being a renewable energy superpower on this website.
No effective resistance to the current heating
James Lovelock (“The Revenge of Gaia”: 2006: page 35) writes that the observed rate of global warming is a grave concern. This rate suggests that no global climate dynamic will effectively resist the current warming and limit temperature increases, thereby keeping the environment safe for life as we know it.
Lovelock points out that the levels of methane and CO2 in the atmosphere in 2006 were comparable to those caused by natural releases of these gases fifty-five million years ago. At this time, temperatures rose between 5 and 8 degrees Celsius, with consequences that lasted approximately 200,000 years.
There is no evidence of a climate dynamic emerging to limit temperature increases.
The danger of global heating amplification
Feedback cycles can produce exponential growth, e.g., the feedback you often get when a person is talking into a megaphone: a slight hum rapidly turns into a painful shriek. Also, the above global heating feedback cycles reinforce one another, each adding to the heating and threatening our nurturing climate. These cycles threaten self-perpetuating, exponential increases in global temperatures. A critical danger is that:
- One of these heating feedback cycles becomes dominant, leading to a cascade of the other heating feedbacks becoming dominant,
- These self-perpetuating dynamics increase global temperatures with increasing rapidity,
- The heating releases vast amounts of greenhouse gases,
- Humans cannot counter this heating as (1) stopping the use of fossil fuels only stops one source of carbon dioxide and does not decrease the levels of greenhouse gases in the atmosphere, and (2) geoengineering will not match the global scale of the many heating feedbacks, &
- The heating destroys our nurturing environment.
We have co-evolved with our climate, so our current climate system suits human beings and the rich diversity of life on our planet. We must protect our climate system because global heating threatens our current climate, the global economy, political stability, human health, and the environment.
Systems theory & feedback
Feedback is a long-established concept central to “Systems Theory”. See my pages:
External Links re feedback
- Climate Change Feedbacks: 10-minute video: UK Meteorology Office
- Feedback loops point to a very hot 21st Century: Science Daily, 6 May 2006
- Greenland Reels: Climate Disrupting Feedbacks Have Begun: Truth-Out: 5/3/2015
Related pages on this site
The physics of tipping points and amplifying feedback
Loaded 2014. Updated 13 Jan 2026