The Polar Express!

The global effects of climate change have become a prevalent issue in the 21^st century. The Arctic ocean is currently warming rapidly (Somavilla et al., 2013), and due to Arctic amplification this region is set to experience a particularly high level of warming in the future (IPCC, 2013). As a result the Arctic has been a key focus of climate change research, with particular emphasis being placed on September sea ice extent. Sea ice extent is important during this month as it reaches an annual minima. Since the 1980s the annual sea ice extent has declined rapidly (IPCC, 2013) (Figure 1).  

Figure 1: Annual sea ice extent (IPCC, 2013)

This week I came across a recently published paper suggesting that Trans-Arctic shipping routes may directly be affected as sea ice extent continues to reach record lows. Smith and Stephenson (2013) used general circulation models to predict the sea ice extent across the Arctic under different emission scenarios. They then applied this to the Arctic Transportation Accessibility Model in order to calculate the fastest route that ships could navigate between the North Atlantic and the Bering Strait. Interestingly Smith and Stephenson (2013) predict that by 2050, ships equipped with appropriate ice-protecting mechanisms will be able to navigate across the North Pole during the summer months (Figure 2). 

Figure 2: New shipping route for Polar Class 6 vessels indicated in red (Smith and Stephenson, 2013). 

Despite the economic benefit of shortening the transportation time, there are concerns about the novel route among conservationists. Crossing the North Pole provides a new opportunity for the spread of invasive species such as mosquitoes, mussels and barnacles, via ballast water and cargo transportation (Palmer, 2013).  

Research suggests that some invasive vascular plant species are already capable of surviving in the Arctic under current climate conditions (Ware et al., 2011). With increased opportunity for invasive species to be introduced, it is likely that these populations will thrive. Additionally as the Arctic ocean warms, conditions are likely to become more favourable for the survival of a wider variety of invasive species (Ware et al., 2013). Scientists are yet to fully understand the impact that invasive species may have on the Arctic region however,  evidence from previous species introductions around the globe suggests that it may dramatically alter the ecosystem. 

Here I have just touched on one way in which climate change will effect the Arctic ecosystem. If you would like to learn about how declining sea ice extent may also have a dramatic effect on Polar Bear populations, then I recommend reading Larissa's Post "Snowball effect: Climate Change and Polar Bear Population Dynamics"

That's all for now!
Elena