Biological Response to Recent Pacific Arctic Sea Ice Retreats

Abstract

Although recent major changes in the physical domain of the Arctic region, such as extreme retreats of summer sea ice since 2007, are well documented, large uncertainties remain regarding responses in the biological domain. In the Pacific Arctic north of Bering Strait, reduction in sea ice extent has been seasonally asymmetric, with minimal changes until the end of June and delayed sea ice formation in late autumn. The effect of extreme ice retreats and seasonal asymmetry in sea ice loss on primary production is uncertain, with no clear shift over time (2003–2008) in satellite‐derived chlorophyll concentrations. However, clear changes have occurred during summer in species ranges for zooplankton, bottom‐dwelling organisms (benthos), and fish, as well as through the loss of sea ice as habitat and platform for marine mammals.

Interdecadal changes in snow depth on Arctic sea ice

“…Conversely, meltwater from thin snow may enhance the formation of melt ponds [Eicken et al, 2004;Petrich et al, 2012], which absorb 1.7 times more solar radiation than bare sea ice and 5 times more than cold, snow-covered sea ice Perovich et al, 2002]. Earlier onset of Arctic sea ice melt has been documented [Markus et al, 2009], and likely contributes to earlier spring phytoplankton blooms and shifts in sympagic-based ecosystems [Arrigo et al, 2008;Wassmann et al, 2011;Grebmeier et al, 2010]. In extremely thin snow cases, little meltwater is produced and melt pond formation can be inhibited [Eicken et al, 2004].…”

Abrupt Climate Changes and Emerging Ice-Ocean Processes in the Pacific Arctic Region and the Bering Sea

“…The diminishing summer ice cover in the western Arctic can have significant impacts on the Arctic and subarctic marine ecosystems (Jin et al 2011;Deal et al 2014, this volume), including a lengthened algae bloom period due to increasing absorption of solar radiation (Grebmeier et al 2006). The present Bering ecosystems and food webs have been experiencing significant changes due to an increase in water temperature (Overland and Stabeno 2004; Grebmeier et al 2010). The Chukchi Sea ecosystems will experience significant changes due to more open water, lengthened growth seasons, and an abundance of biomass.…”

Water mass and bathymetric characteristics of polar cod habitat along the continental shelf and slope of the Beaufort and Chukchi seas

“…Vast expanses of the Arctic Ocean's ice cover have been thinning and shrinking (Perovich and Richter-Menge 2009), with huge ecological implications (cf. Grebmeier et al 2006Grebmeier et al , 2010Adger et al 2007). Ice cover has decreased to the point that large areas may soon be navigable, at least during part of the year (Serreze et al 2007), opening for a variety of environmental and socio-economic impacts, including the exploitation of Wsh resources (cf.…”