Ohio Supercomputer Center Colloquia Series presents:

Amanda Lynch, Assistant Professor of Atmospheric Sciences
Geophysical Institute, University of Alaska Fairbanks
Monash University '86 B.Sc.(Hons) in Applied Mathematics;
University of Melbourne '92 Ph.D in Atmospheric Sciences.

"Development of a Regional Climate System Model of the Western Arctic"

Columbus, Ohio -- March 9, 1995 -- Dr. Lynch was previously involved in many aspects of numerical modeling of the atmosphere at the Australian Bureau of Meteorology Research Centre (BMRC), as part of the Mesoscale Modeling Group, and at the University of Melbourne. These studies ranged from mesoscale weather modeling and real-time forecasting of the tropics and mid-latitudes to long-term global and Antarctic climate studies, concentrating mainly on long term variability, large scale momentum budgets, and surface effects.

She joined the Geophysical Institute in August 1992, and has been developing a regional Arctic climate system model (ARCSyM) for the study of ocean-ice-atmosphere and land-atmosphere interactions and the impact of polar processes upon both the global climate and local weather. Because this model includes many complex processes in the atmosphere, sea ice and ocean, her group is one of the largest users of CPU at the Arctic Region Supercomputer Center, home of the Cray Y-MP M98/41024 denali, a Cray T3D and five advanced visualization laboratories based on Silicon Graphics Onyx reality engines. Dr. Lynch is manager of the ARSC Visualization Laboratory at the Geophysical Institute.

Abstract of presentation:

Development of a Regional Climate System Model of the Western Arctic

A regional atmospheric climate model has been adapted and configured for a western Arctic domain, and is being used as the basis for the Arctic Region Climate System Model (ARCSyM), which will include ice dynamics and thermodynamics, ocean circulation and salinity, and detailed land surface and vegetation representations. After extensive evaluation and development of new Arctic-based physical parameterizations, this model will be used for local and regional scale climate perturbation experiments, to determine the role in and the impact of the Arctic in global climate change.

Model evaluation experiments will be presented, with discussions of the shortcomings of the current model, and some steps that are being taken to alleviate them. In particular, the impact of the cryosphere will be examined, since this aspect of regional scale models has not been well studied in the past, particularly for Arctic conditions. Experiments include simulations involving the impact of the ice phase in clouds and precipitation and the role of sea ice dynamics in the surface energy balance. As well as standard observational analyses and station data, ice drift vectors derived from images from synthetic aperture radar (SAR) imagery obtained from the Alaska Synthetic Aperture Radar Facility (ASF), along with AVHRR and SSM/I imagery, have been used to validate the model at high resolutions.