200 likes | 378 Views
Sea ice modelling, forecasting, and validation activities at Alfred Wegener Institute (AWI), Bremerhaven, Germany. Christian Haas. Modelling Thickness profiling SAR remote sensing. Operating stand-alone & coupled ice-ocean dynamic/thermodynamic models after Hibler & Lemke, Semtner
E N D
Sea ice modelling, forecasting, and validation activities at Alfred Wegener Institute (AWI), Bremerhaven, Germany Christian Haas • Modelling • Thickness profiling • SAR remote sensing
Operating stand-alone & coupled ice-ocean dynamic/thermodynamic models after Hibler & Lemke, Semtner • Viscous-plastic & elastic viscous plastic rheologies • Arctic and Antarctic • Modified and improved by Fischer, Harder, Kreyscher, Hillmer, Lieser • Focus on climate system studies • New: Finite element (FE) modelling
[1/km] [1/km] Ridge frequency
Variability of Arctic sea-ice volume 1951-1999
1951-1999 Spatial thickness and drift trends 1951-1999
1997 Temperature Anomaly (450 m depth) Temperature anomalies in the Arctic Ocean AWI-NAOSIM Temperature flux through Fram Strait
Motivation Accurate Mesh Refinement and Adaptive Meshes Variational Formulation for Complex Rheologies FE Model
SSM/I observations Sea ice model data 8.3.98 8.3.98 Assimilation (OI) Model run (7 days) SSM/I observationsSea ice model data 15.3.98 15.3.98 Assimilation (OI) Model run (5 days) SSM/I observations Sea ice model data 20.3.98 20.3.98 Comparison Assimilation Scheme
SSM/I (observed) Model (stand-alone) Model (assimilation) Result of Assimilation
SIMS: Sea Ice Monitoring System
EM Bird Helicopter-borne EM profiling
Ice thickness variability in the Transpolar Drift: 1991, 1996, 1998 & 2001
Ice Ridging Information for Decision Making in Shipping
SITHOS Sea Ice Thickness Observation System
SITHOS Sea Ice Thickness Observation System Integration of SAR imagery for algorithm development and extrapolation to larger ice regimes Polarstern