2.4 Sea Ice Transport
The ice gathers material from the atmosphere, by overflowing river water in spring
or through freezing of bottom sediments (Pfirman et al. 1997; Harms et al. 2000).
The general scenario is that the pollutants are entrained during the freezing process
and encapsulated by the thickening ice. The ice cover of the Arctic Seas is contaminated by all types of contaminants associated to suspended matter transported
with the river runoff (Borga et al. 2002; Masqué et al. 2007; Pavlov and Stanovoy
2001; Simoes and Zagorodnov 2001). After entertainment, the pollutants are
transported by the motion of the sea ice, driven mainly by Transpolar Drift Stream.
Ice exported from the Siberian Seas to the open Arctic Ocean is then transported
through the Fram Strait towards the North Atlantic, where it melts (Masqué et al.
2007). The rate sea ice export is also influenced by NAO. The ice export is greater
when NAO is positive (Rigor and Wallace 2004).
The Laptev Sea and Kara Sea as recognized as the main source of sedimentladen sea ice in the central Arctic (Pfirman et al. 1997; Rigor and Colony 1997; Hop
and Pavlova 2008). Ice from the Kara and Laptev Seas may reach the Fram Strait in
approximately 2–4 years, but sea ice entering the Beaufort Gyre may circulate even
for about 5–15 years (Masqué et al. 2007).
The annual export of sediments to the North Atlantic by sea ice has been
estimated to range from 7 to 150 × 10
6 tones. This sediment load together with
associated contaminants is released during melting along marginal ice zones
(Masqué et al. 2007). Contaminants released from sea ice may change regional
distribution of contaminants in Fram Strait, the East Greenland shelf, or the Barents
Sea (Pfirman et al. 1997; Zaborska et al. 2010).
The Arctic sea ice cover has been reduced substantially over the last decades
both in terms of area, (with a decline in the summer sea ice extent of more than
10 % per decade between 1979 and 2007), and in terms of volume as indicated by
an observed average thinning of more than 1.5 m since the 80s (Stranne and Björk
2012). The decrease of the ice cover will initially increase flux of contaminants
incorporated into sea ice to the marine ecosystem. However, with the further ice
cover and ice formation reduction this transport pathway for contaminants will have
lower importance.
2.5 Coastal Erosion and Ground Water Discharge
There is little data concerning coastal erosion as discharge process for material to
the marine environment. None of available papers reports discharge of contaminants related to shore erosion. The only studied regions are situated on the Barents
Sea shore, these are Kolguev island, Cap Bolvansky (Vasiliev et al. 2005), and
Climate Change Influence on Migration of Contaminants …
81
The ice gathers material from the atmosphere, by overflowing river water in spring
or through freezing of bottom sediments (Pfirman et al. 1997; Harms et al. 2000).
The general scenario is that the pollutants are entrained during the freezing process
and encapsulated by the thickening ice. The ice cover of the Arctic Seas is contaminated by all types of contaminants associated to suspended matter transported
with the river runoff (Borga et al. 2002; Masqué et al. 2007; Pavlov and Stanovoy
2001; Simoes and Zagorodnov 2001). After entertainment, the pollutants are
transported by the motion of the sea ice, driven mainly by Transpolar Drift Stream.
Ice exported from the Siberian Seas to the open Arctic Ocean is then transported
through the Fram Strait towards the North Atlantic, where it melts (Masqué et al.
2007). The rate sea ice export is also influenced by NAO. The ice export is greater
when NAO is positive (Rigor and Wallace 2004).
The Laptev Sea and Kara Sea as recognized as the main source of sedimentladen sea ice in the central Arctic (Pfirman et al. 1997; Rigor and Colony 1997; Hop
and Pavlova 2008). Ice from the Kara and Laptev Seas may reach the Fram Strait in
approximately 2–4 years, but sea ice entering the Beaufort Gyre may circulate even
for about 5–15 years (Masqué et al. 2007).
The annual export of sediments to the North Atlantic by sea ice has been
estimated to range from 7 to 150 × 10
6 tones. This sediment load together with
associated contaminants is released during melting along marginal ice zones
(Masqué et al. 2007). Contaminants released from sea ice may change regional
distribution of contaminants in Fram Strait, the East Greenland shelf, or the Barents
Sea (Pfirman et al. 1997; Zaborska et al. 2010).
The Arctic sea ice cover has been reduced substantially over the last decades
both in terms of area, (with a decline in the summer sea ice extent of more than
10 % per decade between 1979 and 2007), and in terms of volume as indicated by
an observed average thinning of more than 1.5 m since the 80s (Stranne and Björk
2012). The decrease of the ice cover will initially increase flux of contaminants
incorporated into sea ice to the marine ecosystem. However, with the further ice
cover and ice formation reduction this transport pathway for contaminants will have
lower importance.
2.5 Coastal Erosion and Ground Water Discharge
There is little data concerning coastal erosion as discharge process for material to
the marine environment. None of available papers reports discharge of contaminants related to shore erosion. The only studied regions are situated on the Barents
Sea shore, these are Kolguev island, Cap Bolvansky (Vasiliev et al. 2005), and
Climate Change Influence on Migration of Contaminants …
81