Hidden dangers of climate change: The Arctic is releasing carbon

 Photo by  Annie Spratt

Photo by Annie Spratt

Article I: Introduce problem and causes.

There is at least twice as much carbon stored in the Arctic than there is currently in the atmosphere. It has been lying there undisturbed for thousands of years, unable to reach the air (Cory, R. et al.). Are we at risk of releasing this carbon? And if we do, could it escape to the atmosphere to wreak havoc on our ecosystems?

As the Earth is warming, the Arctic is heating up more rapidly than anywhere else on our planet. Why is the Arctic warming so rapidly? It is just our beloved atmosphere at work, transporting heat from the equator to the poles via large weather systems. The atmosphere and oceans work together to transport heat towards the poles to even out the temperature differences from north to south. Since the heat is pushed towards the poles, the Arctic heats at a faster rate.

The Earth is always trying to reach equilibrium – a balanced state where the temperature is uniform everywhere. The Coriolis force and other natural forces oppose this process and prevent the Earth from ever reaching equilibrium. The accelerated Arctic warming is melting large amounts of ice, decreasing the total ice coverage. The receding ice exposes the underlying dark soil and ocean. This surface absorbs more heat than the bright ice and less of the incoming radiation from the sun is therefore reflected back into space. This is just one of the countless ruinous consequences of Arctic climate change that act to amplify the warming.

Glaciers are not the only things that are melting – the Arctic permafrost is melting too. Permafrost is a layer of soil just beneath the surface that remains permanently frozen throughout the year. As climate change progresses, the Arctic feels its effects more rapidly than any other place on Earth and permafrost has been on the decline. What does this do? The permafrost is holding enormous amounts of carbon, preventing it from escaping into the atmosphere. As we destabilize the permafrost, the carbon that has been lying frozen in the soil for millennia is released and comes into contact with the atmosphere again. What will be the ultimate fate of this newly exposed dissolved organic carbon?

For the past decades, thawing permafrost has become another one of the main feedback mechanisms in global warming but it is a process not yet readily understood. The ice that is holding the permafrost soil together melts and brings with it high concentrations of dissolved carbon. In recent years there have been studies made on the release of both carbon dioxide (CO2) and methane (CH4) from the melting of permafrost, which indicated the potential hazards of these greenhouse gases released from thawing permafrost. I believe this could rapidly become one of the main new driving forces of climate change.

The uppermost part of the permafrost that seasonally thaws and refreezes is called the active layer. Climate change is deepening the active layer in the Arctic permafrost with increased soil temperatures and extensive thawing. These frozen high latitude soils store at least twice the carbon that currently resides in the atmosphere. It is terrifying to think of the effects this would have on our climate if this carbon were to be released as greenhouse gases. The consequences of this level of carbon release would be truly catastrophic.

Ultimately, the fate of this released carbon will depend on different factors, such as its reactivity to sunlight and availability of microbial processing. Having said that, the odds are not in our favour and the Arctic future is looking grim. I hope that if you take anything from this, it is that everything on our Earth is interconnected. Just because you cannot feel the effects right now, does not mean it will not affect you. I personally think of it this way; everything I buy has greenhouse gas emissions associated with it and with each new purchase I am adding to this Arctic – soon to be global – demise. If you have made it this far, I hope that I might have inspired you to keep caring for our planet a little more.

Next article coming Friday 30th.


REFERENCES

  • Cory, R., Crump, B., Dobkowski, J. and Kling, G. (2013). Surface exposure to sunlight stimulates CO2 release from permafrost soil carbon in the Arctic. Proceedings of the National Academy of Sciences, 110(9), pp.3429-3434.


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LIM CONTRIBUTOR

Hannah Rane

Hannah is studying Applied Climatology Masters programme at Birmingham University, after having completed an undergraduate degree in Earth Sciences at the University of Michigan. Hannah is also the creator of the Instagram account @theclimatediaries.

Instagram: @theclimatediaries

Hannah Rane