Geophysical Fluid Dynamics (GFD) is a theme that permeates all the EOS research communities, applying to media as diverse as air, water, ice, mud, magma and rocks, and spanning a huge range of time scales.

Research to improve numerical weather prediction over the west coast mountainous terrain is undertaken using several mesoscale atmospheric models run on large Linux clusters. Applications include ensemble real-time high-resolution regional weather forecasts, air quality modelling, distributed precipitation forecasts for watersheds, forest-fire weather and avalanche weather. EOS research on mesoscale atmospheric dynamics, examines land/sea breeze systems and slope and valley wind systems and is motivated by the desire to understand the distribution and dispersion of air pollutants. The role of eddy fluxes in driving the zonally symmetric atmospheric circulations, the propagation of vorticity waves in fluctuating winds and the influence of coastal geography on oceanic surface winds are being investigated.

Interactions between the ocean and the atmosphere, especially the El Niño-Southern Oscillation and its extratropical effects, are studied using dynamical and neural network models, with applications to seasonal climate prediction. The dynamics of oceans, estuaries, fjords and lakes are investigated by theoretical and numerical modelling, and laboratory and field experiments, with particular focus on mixing processes, horizontal convection and flow over complicated topography such as submarine canyons. In the Strait of Georgia, collaborative field programs, including the use of hovercraft surveys and ferry-mounted instrument packages, are undertaken to study the physical controls on biological processes.

The effects of model scale and heterogeneity on numerical simulation of groundwater flow and solute transport in natural porous media is being studied. Large eddy simulation is used to represent the effects of subgrid-scale dynamics on the large, grid-scale dynamics. The differences in the estimates of submarine groundwater discharge derived from land-based hydrogeological simulation models, direct measurements of discharge on the seabed, and inferences on discharge derived from geochemical tracers are being reconciled, with field sites in the Gulf of Mexico and English Bay.

Non-Newtonian geophysical fluids (e.g. mud, lava and ice) are being modelled mathematically to understand how these materials slump and slide, or create waves on their surfaces. A new numerical model based on Smoothed Particle Hydrodynamics has been developed for the dynamic analysis of rapidly moving flow-like landslides such as debris flows, avalanches and volcanic lahars, and is tested by analyzing laboratory flume experiments with granular materials and real-life landslide examples. Field measurements of cryospheric processes, computational modelling of cryospheric dynamics and the development of theories to describe normal and extreme phenomena are undertaken to increase our understanding of the thermomechanical behaviour of glaciers and ice sheets and to improve the cryospheric component of climate system models.

Transport properties of binary-rock mixtures, including fluid, heat and electrical transport as well as elastic wave propagation are being studied, with percolation models used to predict critical behavior of the transport properties as a function of a varying composition. New pursuits include understanding the cooling and differentiation of planets, especially in how mantle convection leads to volcanism, and how observations and understanding of volcanic processes can be applied to constrain the dynamics of planetary interiors.

Signpost Contributions

Milestone Contributions

(* - more than 25; ** - more than 50; *** more than 100 citations.)