Emissions of carbon containing substances like CO2, CH4 and VOCs including DMS from the marine surface have a climate impact through formation of aerosols or directly as greenhouse gas. Diminishing or change of structure of sea ice is expected to have an effect on the exchange of these carbon containing compounds and thus on the aerosol formation.

In the proposed project we will study the processes controlling the emission of the compounds and the atmospheric transformation processes leading to aerosol formation. We will study the effect of sea ice on the emissions.

Emissions of carbon containing substances like CO2, CH4 and VOCs including DMS from the marine surface have a climate impact through formation of aerosols or directly as greenhouse gas. Diminishing or change of structure of sea ice is expected to have an effect on the exchange of these carbon containing compounds and thus on the aerosol formation.

In the proposed project we will study the processes controlling the emission of the compounds and the atmospheric transformation processes leading to aerosol formation. We will study the effect of sea ice on the emissions.

The project will make the first measurements of the exchange of heat, water and salinity at the entrance to Godthåbsfjord. Continuous measurements will be obtained by deploying moorings off Godthåbsfjord in the relatively shallow shelf area together with hydrographic sections made across the shelf. These measurements will determine the seasonal variation of coastal water masses and their role in the formation of the intermediate water masses in the fjord.

There are two objectives of this field project. The first is to evaluate and compare techniques used in monitoring sea ice algae primary production. The second objective is to use these techniques in determining the environmental cause of uncharacteristically low biomass/production in the fjord. To achieve objective 1, a series of in situ and laboratory incubations will be done to assess potential technique based differences in production rate (14C tracer, oxygen optode, ‘bag incubations’).

We will study the distribution of total and methylated mercury in snow, sea ice (including brine) and underlying water column, with a specific emphasis on 1) how mercury is transported from the cryosphere to the aquatic system via brine and via melt ponds, and 2) whether microbial methylation of mercury occurs in snow, sea ice, or the water column (via sinking particles or copepods).

Site: Kanajorusuit Fjord, Nuuk, Greenland

PI: Fei Wang

We will study the evolution and distribution of pH in first-year sea ice by directly measuring pH profiles in both brine and bulk ice, as well as through experimentally opening a hole in sea ice and monitoring the evolution of ice pH as the sea ice begins to grow, transitions from granular to columnar structure, and develops internal brine volume. These measurements will contribute to a model of carbonate-system dynamics as the natural freezing process transforms seawater into sea ice.

Site: Kobbefjord, Nuuk, Greenland

We will study the exchange of salt, heat, and oxygen between sea ice and the underlying seawater using eddy correlation.  Measurement of ice-ocean oxygen exchange will allow us to non-destructively measure net ecosystem exchange, which will support other primary production estimates made by K.

We proposed to follow the dynamics of the three main (CO₂ – CH₄ and N₂O) green houses gases within sea ice and the interactions sea ice – seawater and sea ice – atmosphere. We will also look at the sediment to determine if there is any contribution from it to the seawater – ice concentration. In addition to the CO2 fluxes between the ice and the atmosphere, we proposed to measure the CH4 and N2O fluxes, which has never been done before. A particular attention will be given to the precipitation of ikaite and its dynamics with the water column.

Large areas with carbonate corrosive sea water have recently been documented in the Canadian Arctic (Yamamoto-Kawai et al. 2009). In parallel, warming of the Arctic is predicted, and observed, to lead to a poleward spread of macrophyte beds, e.g. kelp forests, and increased primary production in shallow coastal waters (Müller et al. 2009, Kortsch et al. 2012, Krause-Jensen et al. 2012).

The use of the H¹⁴CO₃^- incubation technique for estimating marine primary production may arguable be the world’s worst method to gain worldwide acceptance (Anonymous, Gimli Bar 2012). The major source of ambiguity of the 14C‐PP method is whether it is a measure of gross primary production (GPP), net primary production (NPP) or some value in between.