Perennial pack ice in the southern Beaufort Sea was not as it appeared in the summer of 2009

Abstract

[1] In September 2009 we observed a much different sea icescape in the Southern Beaufort Sea than anticipated, based on remotely sensed products. Radarsat derived ice charts predicted 7 to 9 tenths multi-year (MY) or thick first-year (FY) sea ice throughout most of the Southern Beaufort Sea in the deep water of the Canada Basin. In situ observations found heavily decayed, very small remnant MY and FY floes interspersed with new ice between floes, in melt ponds, thaw holes and growing over negative freeboard older ice. This icescape contained approximately 25% open water, predominantly distributed in between floes or in thaw holes connected to the ocean below. Although this rotten ice regime was quite different that the expected MY regime in terms of ice volume and strength, their near-surface physical properties were found to be sufficiently alike that their radiometric and scattering characteristics were almost identical.

Warm Arctic—cold continents: climate impacts of the newly open Arctic Sea

“…Arctic amplification can have multiple causes (Bekryaev et al 2010;Miller et al 2010;Serreze & Barry 2011). While amplification is most traditionally associated with local loss of sea ice and an ice-albedo feedback, polar amplification is also a necessity of poleward heat transport (Langen & Alexeev 2007;Graversen & Wang 2009;Dö scher et al 2010).…”

“…Note the small amount of 5' year sea ice remaining along the Canadian coast and in the southern Beaufort Sea. As a consequence, seasonal ice is becoming the dominant sea-ice type in the Arctic, both in terms of area coverage and volume (e.g., Barber et al 2009). …”

Summertime primary production and carbon export in the southeastern Beaufort Sea during the low ice year of 2008

“…Models and observations show a rapid decline in the summer minimum sea ice extent over the past ten years (Serreze et al 2007;Barber et al 2009;Wang and Overland 2009;Polyak et al 2010) and an increase in the extent and duration of open water areas (Comiso et al 2008;Pabi et al 2008). Climate-related impacts on the biodiversity, ecosystem structure (Gradinger and Bluhm 2005;Grebmeier et al 2006), from planktonic communities to large mammals (Wassmann et al 2011) and on pathways of carbon cycling (Wassmann et al 2004) are already documented for the Arctic Ocean.…”

Lagrangian analysis of sea-ice dynamics in the Arctic Ocean

“…This behaviour is amplified in the Beaufort Sea region (Fig. 6b) during low MYI years, where loss of perennial ice (Barber et al 2009;Krishfield et al 2014) and enhanced geostrophic currents (McPhee 2013) are manifested in a distinct shift in the FTLE PDF to higher values characteristic of increased deformation associated with the emergence of younger and more mobile ice.…”