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OS 072. Phenology of sea ice and ocean algal blooms in the Arctic. Rubao Ji 1 , Meibing Jin 2 , Øystein Varpe 3 1. Woods Hole Oceanographic Institution 2. University of Alaska – Fairbanks 3. Norwegian Polar Institute. OS 072. Phenology of ice algae and phytoplankton blooms in the Arctic.
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OS 072 Phenology of sea ice and ocean algal blooms in the Arctic Rubao Ji1, Meibing Jin2, Øystein Varpe3 1. Woods Hole Oceanographic Institution 2. University of Alaska – Fairbanks 3. Norwegian Polar Institute
OS 072 Phenology of ice algae and phytoplankton blooms in the Arctic Rubao Ji1, Meibing Jin2, Øystein Varpe3 1. Woods Hole Oceanographic Institution 2. University of Alaska – Fairbanks 3. Norwegian Polar Institute
Background Minimum Sea Ice Extent Extent (Million km2) NSIDC 2011 1978
Conceptual model Derived from: Wassman 2011 Søreide et al. 2010 Leu et al., 2011
Implications for zooplankton Calanus hyperboreus Climatology Start 2-weeks earlier Individuals can reach overwinter stage within growth season Ji et al., PiO 2011
Methods • Satellite data analysis: • Ocean color (SeaWiFS) • Ice (SMMR& SSM/I) • Snow (SMMR& SSM/I) • Melt onset: Drobot & Anderson. 2001 Western transect Modeling analysis POP CICE Pelagic food web Ice-algae module LANL/NCAR Model run: 1992-2007 (Jin et al., 2011) Eastern transect
Observation:W. transect Ice-melt Snow-melt SeaWiFS Chl-a
Observation:E. transect Snow-melt Ice-melt SeaWiFS Chl-a
Observation vs model Ice-melt (obs.) Ice-melt (model) • Model capture basic timing pattern • Model skill similar among years • Model phyto peak earlier than obs. Phyto peak Ice melt Phyto peak (model) Phyto peak (obs.) Taylor diagram
Modeled timing A Tice-algae-peak B Tphyto-peak Lag:B-A
Timing correlation corr(Tice-melt, Tphyto-peak)(model) r (all) r (p<0.05) -1.0 1.0 0
Timing correlation corr(Tice-melt, Tice-algae-peak)(model) r (all) r (p<0.05) -1.0 1.0 0
Timing correlation corr(Tice-melt, Lag)(model) r (all) r (p<0.05) -1.0 1.0 0
Summary Earlier phytoplankton bloom Earlier ice-melt Earlier ice-algae bloom Shrinking lag between phyto. & ice-algae blooms only in E. Arctic • Potential henological match/mismatch between algae blooms and zooplankton • Need for further study (model development and validation; more phenology analysis).
Acknowledgement NSF Shelf-Basin Interaction (SBI) project WHOI Arctic Research Initiative IARC, University of Alaska DOE EPSCoR Program Centre for Ice, Climate and Ecosystems (ICE), Norwegian Polar Institute