Antarctic Reflections

To summarise all that I have covered in the last few months I thought it would be useful to reflect on the questions I laid out in my first post.

How is Antarctica responding to a changing climate and what are the spatial complexities?

The effects of climate change on Antarctica are complex: regions have been subjected to different processes, resulting in different effects. I have focused on the three main regions in this blog: The Antarctic Peninsula and East and West Antarctic Ice Sheets (EAIS; WAIS). 

Surface temperature anomaly map for 2017 compared to the 1951-1980 average. It is clear that the Earth has warmed, yet there is spatial complexity. (Image: NASA)

The Antarctic Peninsula has recently experienced some of the most rapid warming (2.5°C since the Industrial Revolution). The effects of this rapid warming are stark: ice shelves have thinned and glaciers are retreating . There is a high certainty that this is caused by anthropogenic climate change. Similarly, the WAIS has experienced ice shelf thinning and channelised melt.  It is becoming more unstable as a result.

In contrast the EAIS is relatively stable, and is even growing in some places, as a warmer climate allows the air to hold more moisture. However, there are other mechanisms of ice loss, such as dynamic ice loss, which could cause it to shrink and become unstable in the future. 

How has Antarctica responded to changing climates in the past?

Artists depiction of a warmer Antarctica (Image: Nature) 

Earth's temperatures have fluctuated on geological time scales, as a result of orbital cycles, greenhouse gases and complex feedbacks. Delving into the past provides some insight into current anthropogenic-driven climate change in the context of natural variability; it is clear that the current changes are unusual in the context of natural variability. 

In the past, the mass balance of Antarctica has fluctuated and resulted in dramatic sea-level change during warmer periods. Whilst this is a warning for future climate change, it is not a direct analogue as there are many complex variables which determine climate. 

What does Antarctica's future look like and what are the implications for the rest of the Earth?

If warming continues it is likely that the EAIS will weaken and the WAIS will become even more unstable, eventually collapsing. Models project implications of different emission scenarios, indicating the importance of meeting emission targets to constrain the melting of the continent. Whilst Antarctica may seem far away, its melt could have a catastrophic effect on global sea levels. 

Climate Change and Antarctica

In this blog I have highlighted the implications of climate change in Antarctica. I have been shocked by the statistics and distressed by the projections. Even as one of the most pristine environments on Earth, Antarctica cannot escape human impact and the implications of climate change on it are likely to be catastrophic, for both the continent and globally. In short, the need for drastic action has never been more apparent.

(Image: Huffington Post)