Monitoring the decline of Arctic ice

Posted by () on Sep 29 2011
VERTIC Blog >> Environment

Kate Farrell, London

Before the introduction of satellites, measuring the extent of Arctic sea ice was an arduous task. Historical studies using shipping logs, exhibitions and diaries give a rough indication of the spread of Arctic ice over hundreds of years. Today, a network of satellites monitor the scope of the ice while on-ice and underwater observations determine changes to the depth. The information provided by these techniques paint a dramatic picture of the future of the Arctic region. It is therefore important that they are understood, appreciated, and improved.

The view from above
In 2007, Arctic ice reached a record low and continues to decline at a rapid rate. In 2007, the extent of the sea ice was 4.28 million square kilometres (or 1.65 million square miles). When compared with the 2005 figure of 5.57 million square kilometres (2.14 million square miles), this was a large drop. On September 10 2011, the US National Snow and Data Center reported that to date, the sea ice had declined to 4.34 million square kilometres (1.68 million square miles). Satellite images were used to confirm this data, which shows that we are not far away from the 2007 low.

The beauty of satellite monitoring is that it provides a bird’s-eye view of the daily changes in Arctic ice shelf composition over long periods of time. With such constant coverage, daily changes in the composition of the Arctic ice shelf can be understood and modelled over long periods of time. NASA provides an animation which shows the extent of arctic sea ice decline since 1979.

Beyond scientific surveying, satellite monitoring can also serve other ends. With near real-time coverage, governments and industries can monitor exactly where and when Arctic sea ice is open during the summer. Openings in the Arctic ice can allow maritime access to the Northwest and Northeast Passages which link the Pacific and Atlantic oceans. These shortcuts are profitable to the shipping industry, and are strategically important to the surrounding states. These passages opened for the first time in 2007, and opened again in August, allowing a succession of tankers to pass through on the way to Thailand. Long-term access to this data can help create models to estimate when these passages will open again, and for how long.

The view from the ground
Although satellite imaging can monitor the extent of ice retreat, technical limits prevent it from reliably monitoring changes in depth. The thickness of the ice is important as it directly correlates to the extent that melting ice will retreat. Newer, thinner ice is likely to melt more often and to a greater extent, whereas older, thicker ice will remain solid for longer.

The breadth of sea ice is monitored using on-ice and underwater observation techniques. On-ice observation techniques include boreholes, radar technology, magnetic field probes, and mechanical drilling. In 2009, a small team from the Catlin Arctic Survey trekked 432 kilometres over the ice, pulling a radar behind them. The suitcase-sized ‘SPRITE’ radar broadcast radar waves through the ice and detected the returning waves which were reflected by the ice-water boundary underneath. This advanced technology allowed explorers to gather data on ice depth every 10 meters; a major feat in Arctic exploration. The team also took drilling samples to calibrate data gained from the survey.

The view from below
Beside satellites and on-site sampling techniques, Arctic ice can be monitored from below. Submarines can cruise beneath the ice using upward looking sonar to gather data on ice composition. To do this, the US Navy and Royal Navy submarines use the ‘Digital Ice Profiling System’ (DIPS). This data is then released to the US Army’s Cold Regions Research and Engineering Laboratory (CRREL) and Scott Polar Research Institute at Cambridge University.

Multilateral governance of the Arctic
Variations in global climate can have a significant impact on the changing landscape of the Arctic region. The techniques described above therefore play an important role in monitoring the global shifts in climate. However, melting Arctic ice can affect the world for a few different reasons. States surrounding the Arctic region uphold territorial interest in the Arctic, as the borders among them begin to blur as they extend north in to the ice. These divisions have yet to be determined, and as the ice retreats, competing claims over some Arctic areas become increasingly important.

However, the Arctic Council, set up by the Ottawa Declaration in 1996, is working towards making decisions on these claims multilateral. The Council is a high-level, intergovernmental forum that provides ‘a means for promoting cooperation, coordination and interaction among the Arctic States, with the involvement of the Arctic Indigenous communities and other Arctic inhabitants on common Arctic issues’. The members of this council are Canada, Denmark (including Greenland and the Faroe Islands), Finland, Iceland, Norway, Russia, Sweden, and the US.

Sweden currently holds the chairmanship of the Council, which has been directed by the common objectives shared by Sweden and previous chairs Norway and Denmark. Climate change and integrated resource management are at the top of these goals. For climate change, the three chairs sought to fulfil the recommendations of the Arctic Climate Impact Assessment (ACIA) Policy Document.

With regard to integrated resource management, the chairs wanted to strengthen discussion on the topic, while upholding a particular emphasis on environmental protection. The estimated commercial value of Arctic resources is huge. Many companies have major plans for gas, oil, and mineral exploration, and less ice creates opportunity for more fishing. As the Arctic ice continues to shrink, the discussions within the Arctic Council will inevitably become more pressing, and the outcomes more urgent.

Controlling the seas
A knock-on effect of territorial expansion into the Arctic region will be felt within the shipping industry. As discussed above, melting ice can open important shortcuts in shipping routes. However, routine use of these passages will not be without issues. Similar to the Suez and Panama canals, the states which control these shortcuts could also control the ships which pass through them. When the Northwest and Northeast passages can save companies up to 40% on shipping costs, control of these passages can seem attractive. With respect to the Northwest Passage, Canada has already exercised its territorial claim. However, Russia and the US are campaigning for all states to have freedom of passage, as with the Suez and Panama Canals.

Controlling the land
A US Geological Survey estimated that the Arctic could have up to 13 percent of the world’s undiscovered oil and 30 percent of its undiscovered natural gas reserves. As territorial claims among the five Arctic states are already cause for concern, rights to the resources will be a contentious issue. In 2007, Russia made the symbolic gesture of planting its national flag on the Arctic seafloor. In doing this, Moscow quickly noted that this act gives them no legal rights to the territory. However, this move signals that they may be ready to try to claim them.

Rights to the continental shelf are also proving troublesome. Under the exclusive economic zone, mandated through United Nations Convention on Law of the Seas (UNCLOS), every state has territorial claim extending 200 miles from their coast. However, this can be extended if the continental shelf continues beyond this. One such disputed shelf is the Lomonosov Ridge which runs from Siberia to North America. The ridge links Canada to Russia and both dispute the other’s claim of the area.

The future of Arctic ice monitoring
Each summer we see the effect of climate change as Arctic ice declines at an unprecedented rate. Satellite, on-ice, and under-sea observation techniques provide us with clear evidence of this. Clearly, this downward trend in Arctic ice coverage may have significant effects on all states, not just those within the Arctic region. These monitoring techniques should be fully appreciated, and improvements should be sought by all states. The insights they provide can not only help demonstrate the extent of climate change, but also inform decisions on how to deal with its effects. The more information that is available, the better informed states will be to make responsible decisions about use of the region and its resources.


Last changed: Sep 29 2011 at 7:06 PM




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