Soil microbes define dangerous rates of climate change

The rate of global warming could lead to a rapid release of carbon from peatlands that would further accelerate global warming.

Two recent studies published by the Mathematics Research Institute at the University of Exeter highlight the risk that this 'compost bomb' instability could pose, and calculate the conditions under which it could occur.

The same Exeter team is now exploring a possible link between the theories described in the studies and last summer's devastating peatland fires in Russia.

The first paper is published in the European Journal of Social Science and the second in .

The first paper by Catherine Luke and Professor Peter Cox describes the basic phenomenon. When decompose they release heat – this is why compost heaps are often warmer than the air around them.

The compost bomb instability is a runaway feedback that occurs when the heat is generated by microbes more quickly than it can escape to the atmosphere. This in turn requires that the active decomposing soil layer is thermally-insulated from the atmosphere.

Catherine Luke explains: "The compost bomb instability is most likely to occur in drying organic soils covered by an insulating lichen or moss layer".

The second paper led by Dr Sebastian Wieczorek and Professor Peter Ashwin, also of the University of Exeter, proves there is a dangerous rate of beyond which the compost bomb instability occurs.

This is in contrast to the general belief that tipping points correspond to dangerous levels of global warming.

Sebastian Wieczorek explains: "The compost bomb instability is a novel type of rate-dependent climate tipping point".

The Exeter team is now modelling the potential impact of the bomb instability on future climate change, including the potential link to the Russian peatland fires.It is also working to identify other rate-dependent tipping points.


Explore further

Compost can turn agricultural soils into a carbon sink, thus protecting against climate change

More information:
-- Soil carbon and climate change: from the Jenkinson effect to the compost-bomb instability onlinelibrary.wiley.com/doi/10 … 010.01312.x/abstract
-- Excitability in ramped systems: the compost-bomb instability rspa.royalsocietypublishing.or … 0.0485.full.pdf+html
Citation: Soil microbes define dangerous rates of climate change (2010, November 29) retrieved 22 October 2019 from https://phys.org/news/2010-11-soil-microbes-dangerous-climate.html
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Nov 29, 2010
make some stuff up to support more agw lunacy. The planet had periods in which it was much warmer than it is today, those tipping points are a bs line to scaremonger people into green fascism.

Nov 29, 2010
It can be difficult to compare climate given the continents are now in different positions.. however..extract from wikipedia on the Eocene Period" The most prominent of these(hyperthermal)events was the Paleocene-Eocene Thermal Maximum or Initial Eocene Thermal Maximum (PETM or IETM), which began at the Paleocene-Eocene Boundary. During this episode. Earth surface temperatures rose by 5-7 °C.[2] The PETM coincided with a major mammalian turnover on land (that distinguishes Eocene fauna from Paleocene fauna), and an extinction of many benthic foraminifera species in the deep sea." In this turnover means "died out"

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