• Most of what we know regarding the biology of
(Arctic) sea ice is biased toward summertime basal ice
• Most biomass
• Easiest access
• Microbial activity in sea ice occurs throughout the
annual cycle (Junge et al. 2004)
• Bacterial are distributed throughout the ice column,
concentrating at the top and bottom (Bowman and Deming,
2010)
Grossman and Dieckmann, 1994
• Sharp environmental gradients and other stressors at
the top and bottom of the ice column may induce
physiological responses of significance to chemistry
and physics
• DMSP production and conversion to DMS (T, S,
UV)
• Methylhalide formation, including iodomethane
(S, UV, H2O2)
• EPS production (S, T, UV)
• C export
• Calcium carbonate polymorph selection
• Brine channel blockage
• Enhanced connectivity
• Biologically active ice is more connective
than sterile ice
• Implications for permeability of gas
• Implications for nutrient renewal
• Implications for ice strength
• Limitations of laboratory study
• EPS varies in concentration and
composition
• At this time don’t know how
changing EPS will impact the
properties of sea ice in the future
Community
composition
Physiological
state
Physical and
chemical
impact
Krembs, Eicken, and Deming, 2011
Integrating into MOSAiC – Establishing a baseline
for predictive (physio)biogeochemistry
• Given a set of chemical and physical
conditions who is present, how many are
there, and what are they doing that feeds
back to the initial conditions?
• Basic biology is lacking for the central
Arctic, little effort or equipment is required
for a long time series of basic parameters
Krembs et al. 2002
+
• In addition at key time points detailed
community composition* should be
assessed in combination with rate measures
and flux measures
+