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Sandilands, J. W.

Publications and source records attributed to Sandilands, J. W..

Calculations of Arctic ozone chemistry using objectively analyzed data in a 3-D CTM

A three-dimensional chemical transport model (CTM) (Kaminski, 1992) has been used to study the evolution of the Arctic ozone during the winter of 1992. The continuity equation has been solved using a spectral method with Rhomboidal 15 (R15) truncation and leap-frog time stepping. Six-hourly meteorological fields from the Canadian Meteorological Center global objective analysis routines run at T79 were degraded to the model resolution. In addition, they were interpolated to the model time grid and were used to drive the model from the surface to 10 mb. In the model, processing of Cl(x) occurred over Arctic latitudes but some of the initial products were still present by mid-January. Also, the large amounts of ClO formed in the model in early January were converted to ClNO3. The results suggest that the model resolution may be insufficient to resolve the details of the Arctic transport during this time period. In particular, the wind field does not move the ClO(x) 'cloud' to the south over Europe as seen in the MLS measurements.

Kaminski, J. W.↗

Modelling stratospheric polar ozone using objective analysis

We have studied the development of the austral ozone hole using a 3-D spectral chemical transport model at R15 resolution for the period 15th September to 15th October, 1991. The model is driven by objectively analyzed wind fields obtained from the Canadian Meteorological Center and uses the chemical module developed by Kaminski (1992). Although extensive processing of NO(y) and Cl(x) occurs within the model, the ozone hole that develops appears shallow and ephemeral. Analysis of the results indicate that the meridional transport of ozone is sufficient to overwhelm the substantial chemical depletion that does occur. We suggest that the low resolution objectively analyzed data used is unable to capture the essential isolated nature of the vortex.

Sandilands, J. W.↗