Sea ice phenology and timing of primary production pulses in the Arctic Ocean

Abstract

Arctic organisms are adapted to the strong seasonality of environmental forcing. A small timing mismatch between biological processes and the environment could potentially have significant consequences for the entire food web. Climate warming causes shrinking ice coverage and earlier ice retreat in the Arctic, which is likely to change the timing of primary production. In this study, we test predictions on the interactions among sea ice phenology and production timing of ice algae and pelagic phytoplankton. We do so using the following (1) a synthesis of available satellite observation data; and (2) the application of a coupled ice-ocean ecosystem model. The data and model results suggest that, over a large portion of the Arctic marginal seas, the timing variability in ice retreat at a specific location has a strong impact on the timing variability in pelagic phytoplankton peaks, but weak or no impact on the timing of ice-algae peaks in those regions. The model predicts latitudinal and regional differences in the timing of ice algae biomass peak (varying from April to May) and the time lags between ice algae and pelagic phytoplankton peaks (varying from 45 to 90 days). The correlation between the time lag and ice retreat is significant in areas where ice retreat has no significant impact on ice-algae peak timing, suggesting that changes in pelagic phytoplankton peak timing control the variability in time lags. Phenological variability in primary production is likely to have consequences for higher trophic levels, particularly for the zooplankton grazers, whose main food source is composed of the dually pulsed algae production of the Arctic.

Intra-seasonal variation in zooplankton availability, chick diet and breeding performance of a high Arctic planktivorous seabird

“…Both colonies are situated in the area where Atlantic, Arctic and glacial waters converge, mix and exchange (Saloranta and Svendsen 2001). The timing of ice retreat and peaks of pelagic phytoplankton bloom are similar in both areas [according to 10-year data for 1998-2007 (Ji et al 2013) and sea ice data for the studied year (Norwegian Ice Service, http://polarview.met.no/)]. To our knowledge, there are no detailed data on zooplankton phenology of C. glacialis in the studied areas; however, given environmental conditions both studied areas probably represent Kongsfjorden phenological icefree scenario (Daase et al 2013).…”

Advection in polar and sub-polar environments: Impacts on high latitude marine ecosystems

“…Early ice retreat and thinner ice will lead to an increase of irradiance in the water column and under the ice, which may shift the onset of ice algal and phytoplankton production to earlier in the season (Arrigo and van Dijken, 2011;Frey et al, 2011;Ji et al, 2013). Conversely, expanded areas of open water may delay the phytoplankton bloom due to wind-induced mixing delaying the formation of the seasonal pycnocline, as is apparently the case in the eastern Bering Sea (Baier and Napp, 2003;Bluhm and Gradinger, 2008;Hunt et al, 2011).…”

Arctic in Rapid Transition: Priorities for the future of marine and coastal research in the Arctic

“…Shifts in biodiversity can directly and indirectly change species interactions and ecosystem processes resulting in large cascading changes with implications for the entire Arctic ecosystem (Slagstad et al, 2011;Wassman et al, 2011;Ji et al, 2013;Post et al, 2013;Kę dra et al, 2015a) and thus for ecosystem services (e.g., food production in the form of fisheries but also the cultural heritage of hunting practices as well as tourism). As current observations and predictions suggest an icefree Arctic summer likely to occur within the next few decades (Cavalieri and Parkinson, 2012) possible effects of Arctic biodiversity are of critical concern.…”