JISAO/PCC Postdoc Candidate Seminar: Mass balance, salinity of the polar sea ice caps and perspectives for ecosystem modeling

Start Date/Time: Friday, June 27, 2008, 1:00 PM
Location: ATG 310

Sea ice is widely known for its large climate sensitivity and physical feedbacks. Much less is known on its potential impact on biogeochemical cycles and oceanic carbon uptake. In this contribution, first, results from physical sea ice modeling are presented. Then, perspectives on polar ecosystems modeling are discussed.

More precisely, I show first of all how a more detailed representation of sea ice physics in an ice-ocean model improves the simulated large-scale ice / ocean characteristics in a global (i.e., including Arctic and Antarctic) hindcast of the last 30 years.

Second, I present results suggesting that sea ice salinity should be included in ice models used for climate simulations. Sea ice has long been known to be a saline medium. Moreover, sea ice salinity proves to vary in space and time, which has a significant impact on the sea ice thermal properties. It is shown here how including salinity in an ocean-sea ice model (with subgrid-scale sea ice thickness distribution) affects the simulated ice volume and upper ocean stratification in both polar regions.

Finally, I use preliminary results (on nutrient transport, light availability and ice-air CO2 fluxes) to draw perspectives on the large-scale simulation of polar sea ice ecosystems and carbon cycle.