Losing permafrost -Santa in trouble!

Happy new year everyone! I grab this opportunity to travel north, near Santa’s house, to write about the soil carbon ‘under’ the snow. 

As you know, nowadays, the snow on the poles melts faster in comparison to the previous years, affected by the human activity and the global warming. You can check some of my classmates’ blogs concerning the climate change in Arctic (check right in the blog column). It is time for me to add something about the soil carbon.

Lands near north pole, where frozen soil layers are observed all over the year, have become large carbon storage and they can be characterised as carbon emitters due to microbial activity and the global warming (Charles D. Koven et al., 2011). During the summer season the top layer of the soil (active layer) thaws and refreezes at winter leaving only the layer below it permanently frozen.

The permafrost layer

This permanently frozen ground is very important reservoir for soil carbon although is not usually taken under consideration in many studies about the global carbon budget (Sergey A. Zimov et al. 2006). An example of the crucial role of the carbon release from the frozen layer, is the carbon emission at the end of the last glacial age, when the snow retreated back in northern latitudes. In this period, a potential reduction of soil carbon from 2.6% to 0.15% could have released up to 500 Gt of carbon (Sergey A. Zimov et al. 2006).

 Exposed carbon-rich soils from the Kolyma River in Siberia (Sergey A. Zimov et al. 2006)

 It could be easily noticed, that the microbial activity in the soil in combination with the global warming can give a positive feedback in the climate change. Hence, the rising temperature will continue to melt down the snow resulting in soil carbon decomposition (Edward A. G. Schuur et al., 2008). 

Modelling the permafrost declining (CIRES)

In the figure above, we can observe the climate change impact on the permafrost areas. The simulation shows the reduction of these areas over a century. As a result, carbon will be released back into the global cycle and this will contributes in the global warming.

See you in the next post and let’s hope we will be able to pay a visit to Santa’s home the following years.