Germany’s Klimanachrichten here presents peer-reviewed climate science that shows permafrost is not a tipping point we need to worry about. [emphasis, links added]
Here’s the text of what is reported in the video:
Permafrost soils store a lot of CO2 and are often described as a critical tipping element in the Earth system, which suddenly and globally collapses above a certain level of global warming.
Yet, the view of a ticking time bomb that initially behaves rather calmly and only ignites at a certain warming threshold is controversial among researchers.
According to scientific data, this claim is not correct, as an international study team led by the Alfred Wegener Institute has now been able to show.
According to the study, there is not one specific global climate tipping point, but many local and regional tipping elements that “ignite” at different times, accumulate over time, and cause the permafrost to thaw in step with climate change.
Permafrost soils cover around a quarter of the land area in the northern hemisphere and store vast amounts of organic carbon in the form of dead plant remains. These are not decomposed when frozen.
Only when the permafrost thaws do microorganisms become active and release a lot of carbon into the atmosphere as CO2 and methane. Rising global temperatures could therefore activate these gigantic reservoirs and massively increase climate change through additional emissions.
In the public debate, there is repeated talk of a “ticking carbon time bomb”. This is based on the assumption that permafrost, like the Greenland ice sheet, is one of several tipping elements in the Earth system.
According to this, the permafrost initially disappears only slowly in the course of global warming. Only when a critical threshold value is exceeded do the thawing processes suddenly intensify themselves and a rapid, irreversible global permafrost collapse sets in.
Although such a thawing scenario is often suspected, it has not yet been possible to clarify whether such a threshold value really exists and at what temperature it could be exceeded.
An international research team led by Jan Nitzbon from the Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research (AWI) has now gotten to the bottom of this question.
The AWI researcher explains:
“In fact, the depiction of permafrost as a global tipping element is controversial in research. The Intergovernmental Panel on Climate Change (IPCC) also points out this ambiguity in its latest assessment report. We wanted to close this knowledge gap.
“For our study, we compiled the available scientific literature on the processes that can influence and accelerate the thawing of permafrost.
“Underpinned by our own data analysis, we evaluated all current findings on thawing processes to determine whether and on what spatial scale – local, regional, global – they can lead to self-sustaining thawing and thus to a ‘tipping point’ at a certain warming threshold.”
The results of the study clearly show that there are self-reinforcing, partly irreversible geological, hydrological, and physical processes, but these only have a local or regional effect.
One example is the formation of so-called thermokarst lakes. This involves ice melting in permafrost soils, which then sink. The meltwater collects on the surface and forms a dark lake that absorbs a lot of solar energy.
This further increases the warming of the permafrost beneath the lake and creates a self-perpetuating dew process in the area around the lake.
Similar amplifying feedbacks were also found in other processes relevant to permafrost, such as the loss of boreal coniferous forests due to fires – but here too only on a local to regional scale.
There is no evidence for self-reinforcing internal processes that would simultaneously affect the entire permafrost above a certain degree of global warming and accelerate thawing globally.
Even the estimated release of greenhouse gases would not lead to a global leap in global warming at least until the end of the century. The depiction of permafrost as a global tipping element is therefore misleading.
The study was published in Nature Climate Change in June 2024.
Top photo: Aerial view of permafrost soils in northwestern Canada (Photo: Alfred Wegener Institute/Guido)
Read more at No Tricks Zone
This Tipping Point Poppycock/Balderdash is as stupid as the idea of Guam Capsizing and Sinking and this Fragile Earth Delicate Balance of Nature stuff