SCPs in the Arctic (Arctic Pollution Part II)

Continuing from the last post on Arctic pollution, this post will look at the pollution record from Svalbard, a remote island off the coast of Norway high into the Arctic circle.

Due to it's remoteness, it's a great place to look for traces of long-range pollution transported from industry and agriculture in the Northern Hemisphere, especially from Russia. Many studies have found evidence of such long range contamination which gets to the Arctic via the atmosphere, rivers and oceans.

A more systematic study was carried out by a number of academics in the 1990s using lake sediments which, as we've learned, give a record of pollution far longer than atmospheric measurements can. For example, it's possible to estimate pre-industrial levels of pollution using this method. One paper from this study by Rose et al. (2004) was especially interesting and showed significant local sources of pollution, something I found surprising for such a
remote area. Looking into it further, it appears that local sources of pollution from agriculture and oil mining activities are also causing pollution levels from local sources to increase.

Spheroidal Carbonaceous Particles (SCPs) are produced by fossil-fuel combustion and are detectable in lake sediments. Rose et al. found recent elevated levels of SCPs at 18 out of the 21 lakes studied, and in the other three it's likely that they were present but below the detectable levels. Besides showing that these remote sites have some level of contamination, these results show the effect of local power stations when plotted against distance from them (eg from the power station at Longyearbyen, see graph below). Therefore, even in the high Arctic, there are local pollution sources that have left a significant and obvious record.

Direct from Rose et al (2004)

What I found interesting, though, were the levels of Polycylcic aromatic hydrocarbons (PAHs) found at the bottom of the core which corresponded to pre-industrial conditions. Unexpectedly, in many of these samples PAH levels were much higher than in the surface sediments! The authors report contamination during coring and sample preparation is unlikely, and so propose that whale-blubber processing on a large scale during the 16th and 17th centuries may be the cause of elevated pre-industrial PAH levels. It's highly possible, therefore, that localised activity centuries ago caused raised pollutant levels, meaning it's not just the widespread industrial and agricultural activities of the past c.150 years that have polluted the Arctic. Personally, I found this possibility surprising, and quite interesting!

Surface sediment and pre-industrial levels of PAHs (ng g^-1). 'nd' = undetectable levels
Direct from Rose et al (2004)

Although almost any level of pollution is undesirable, the paper compares levels found at Svalbard to other European sites closer to large populations. Site U (shown above) is described as only having received 'moderate' contamination, and Site S (also above) as having pollutant levels comparable to the 'cleanest European mountain sites'. This contextualisation helps to put these results into perspective.

It's clear that levels of pollution on Svalbard are elevated above 'natural' levels, even though it's an extremely remote location, destroying images of an untouched Arctic Wilderness. What I found surprising though, was the possibility that these areas have been 'contaminated' for hundreds of years through whaling activities. Finding out how all types of pollution I've looked at in these last two posts is affecting biota, however, is very difficult. Pollution levels are low, so detecting any ecosystem changes that can be directly linked to pollution is unlikely. Also, these areas are remote, and as with every study I've looked at in this blog, the environment is a product of a large number of related factors.

What is needed is further work, such as that done by the Arctic Monitoring and Assessment Program (AMAP) to continue to monitor pollution levels, as well as laboratory studies concerning the effect of 'new' POPs on biota. The potential for increase of local pollution is worrying though, especially with the prospect of greater oil mining activities in the high Arctic due to ice melt. Already, significant levels of POPs have been found in blood and breast milk of native populations in the high Arctic who, in general, do not pollute the environment, raising ethical and even moral questions about who ends up suffering from increased activity in the Arctic. Governments should ensure the rush for oil in the Arctic doesn't mean that environmental issues don't get pushed aside, for the sake of the local populations.