Phenology of sea ice and ocean algal blooms in the Arctic
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Transcript of Phenology of sea ice and ocean algal blooms in the Arctic
Phenology of sea ice and ocean algal blooms in the Arctic
Rubao Ji1, Meibing Jin2, Øystein Varpe3
1. Woods Hole Oceanographic Institution2. University of Alaska – Fairbanks3. 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 Institution2. University of Alaska – Fairbanks3. Norwegian Polar Institute
OS 072
Background
Minimum Sea Ice Extent
1978 2011
Ext
ent
(Mill
ion
km2)
NS
IDC
Conceptual model
Derived from: Wassman 2011 Søreide et al. 2010 Leu et al., 2011
Implications for zooplankton
Calanus hyperboreusClimatology Start 2-weeks earlier
Ji et al., PiO 2011Individuals can reach overwinter stage within growth season
Methods
Modeling analysis
Satellite data analysis:•Ocean color (SeaWiFS)
•Ice (SMMR& SSM/I)
•Snow (SMMR& SSM/I) Melt onset: Drobot & Anderson. 2001
Western transect
Eastern transect
POPPOP CICECICE
Pelagic food web Pelagic
food web Ice-algae module
Ice-algae module
LANL/NCAR
Model run: 1992-2007(Jin et al., 2011)
Observation: W. transect
Snow-melt
Ice-melt
SeaWiFSChl-a
Observation: E. transect
Snow-melt Ice-melt
SeaWiFSChl-a
Observation vs modelIce-melt (obs.) Ice-melt (model)
Phyto peak (obs.) Phyto peak (model)
Taylor diagram
- Model capture basic timing pattern
- Model skill similar among years
- Model phyto peak earlier than obs.
Phyto peak
Ice melt
Modeled timing
BTphyto-peak
Lag: B-A
ATice-algae-peak
Timing correlation
corr(Tice-melt, Tphyto-peak) (model)
r (all) r (p<0.05)
0-1.0 1.0
Timing correlation
corr(Tice-melt, Tice-algae-peak) (model)
r (all) r (p<0.05)
0-1.0 1.0
Timing correlation
corr(Tice-melt, Lag) (model)
r (all)
0-1.0 1.0
r (p<0.05)
Model results: W. transect
Summary
Earlier ice-meltEarlier ice-melt
Earlier phytoplankton bloomEarlier phytoplankton bloom
Earlier ice-algae bloomEarlier ice-algae bloom
Shrinking lag between phyto. & ice-algae blooms
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