Arctic climate feedbacks

The greatest risk from global warming to humanity and all life
​is the multiple combined 'cascading' Arctic climate feed backs.  

These are the following. 
o Melting back of subarctic ​spring-summer snow cover. 
o ​
Melting decline of Arctic summer sea ice extent.​
o ​
Warming far north peat lands - emits methane. 
Thawing permafrost - emitting methane & nitrous oxide. 
Melting sea floor Arctic methane hydrate - methane.
Methane and nitrous oxide are much more powerful greenhouse gases than CO2.
Methane from of sub sea floor methane hydrates.
Positive feedback from warming may cause the release of carbon or methane from the terrestrial biosphere and oceans (See Meehl et al., 2007), which would add to the mitigation required.  
Quote from IPCC AR4 2.2.4 Risk of catastrophic or abrupt change.

Positive and negative feedback ​​
There are two kinds of feedback in terms of amplifying warming (+ve) or reducing warming (-ve)​.

We are most used  to negative feedback systems used for safety. If a heater gets to hot there is a built -ve feedback ​​that switches it off. 

But in the climate system there is no such safety mechanism- feedbacks act in the dangerously +ve feedback way. ​​

​​In the case of ​ global climate change positive feedbacks to global warming lead to more global warming. Global warming causes more global warming 

Furthermore the ​​increased warming  ​accelerates over time and temperature.
Climate system +ve feedback is a global warming impact multiplier.​

​​Considering all the feedbacks the +ve ​feedbacks are incomparably larger the -ve, and
​the more the warming the larger the +ve  ​feedbacks (but not the -ve).

Positive feedbacks that operate by the planet emitting more carbon dioxide (CO2) or methane (CH4) are  +ve carbon (cycle) feedbacks.​​
By definition positive carbon feedback is the greatest risk caused by global warming - because our industrial global warming responds by emitting carbon GHGs CO2 and methane and that boosts global warming more that increases carbon feed back even more etc... - in the ultimate vicious cycle.

​​​​There are a great many of the +ve feedbacks and Earth has vast pools (stores) of carbon vulnerable to global warming- the largest being Arctic.

​​The warming planet emits CO2 methane and nitrous oxide- thawing permafrost is doing all this now.

​​​​Climate system positive feedbacks or loops tend to be self perpetuating and accelerating making them catastrophically dangerous.  

One positive feedback ​​may increase one or more other positive feedbacks - 'cascading' feedbacks, which leads to runaway rapid warming.
​The big example is the Arctic involving Arctic methane. 

​​​​​​​There are unforeseen positive feedbacks
The ​melting of glaciers forms deep channels of water torrents and lake at
​the glacier base lubricating its retreat.

​​​​Fast and Slow feedbacks​​
There are 2 ​sorts of feedbacks in terms of their speed of response.

​Fast feedbacks (or Charney feedbacks) are the only ones accounted for
​by the IPPC in global warming projections are the fast feedbacks.
​These act on an immediate time scale and are water vapor, clouds
​ (+ve & -ve) aerosols (+ve and -ve). latest research confirms the strong
​ wate​r vapor feedback and that clouds have a net positive (bad) feedback

Water vapor is a GHG and the largest +ve feedback.
It about doubles the warming caused by a GHG alone.​
​Warm air holds more water as global warming increases ​so amplifying
​the global warming by a factor of 2 for warming by GHG alone.
​It is a fast feedback

Slow feedbacks are much ​slower to respond to warming, but as they do
​they are very large and can lead to catastrophic accelerating degrees of

​​They are the albedo cooling loss from the loss of ice sheets, warming wetland
​peat (high carbon), thawing permafrost (CO2 CH4 N2O) and sub sea floor methane. 

These large slow feedback are excluded by the IPCC global warming projections
​​in the assessments. They are also not included in the calculation of the all
​important climate sensitivity.

Climate Emergency Institute

Ice cores show that warm interglacial periods are from feed-back emissions triggered by a tiny increase in insolence Causal feedbacks in climate change
The Arctic has switched from carbon sink to source with accelerating ​Arctic permafrost feedback underway(NOAA 2019 Arctic Report Card)
Amazon is now a carbon source  confirmed ( 2021)
2021 VIDEOs Climate Emergency Feedback 
Surface Ozone: surface ozone is a greenhouse gas- it's formation is increased by surface heat, making it a major ignored global warming  feedback​
It is a toxic air pollutant​ to human health, and also toxic to green plants

Increasing surface ozone in combination with high temperatures will ​​reduce crop yields 
Atmospheric methane's explosive increase from wetland feedback emissions
20 March 2023, Recent intensification of wetland methane feedback, Zhen Zhang et al From Tropical wetlands (largest S. America) High-latitude wetlands appear to have only moderate CH4 increases
We determine that wetlands will form the majority of the CH4 climate feedback up to 2100​  March 2018 Methane Feedbacks to the Global Climate System in a Warmer World, J.F. Dean et al
+ve means amplifying (bad) 
Double click here to edit this text.
The Arctic holds most of the largest amplifying feedback sources
and the Arctic is warming 3-4 times the rest of the planet
Double cli

​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​ck here to edit this text.
Warmed soils emit more CO2
(carbon feedback)​
+ve/ Amplifying feedbacks to global warming