Seasonal Variations in the Spatial-temporal Dependence of Total Column Ozone

Summary: The Total Ozone Mapping Spectrometer (TOMS) is a satellite-based instrument that measures total column ozone on a daily basis over a fairly dense spatial grid with near global coverage. Statistical models for the spatial-temporal variations in total column ozone provide insights into ozone dynamics, are valuable for obtaining inferences on long-term trends in ozone levels, and can be used to predict ozone levels at unobserved points in space-time. However, developing such a model is complicated by the seasonally varying nature of the space-time dependence and the partial confounding of spatial and temporal variation caused by the sun-synchronous orbit of the satellite. This work considers methods for describing, modeling and estimating the seasonal patterns in the dependence structure for measurements at a single latitude. Applying one of these models to the synoptic prediction of total column ozone at a latitude shows that there is at least the potential for substantially improved predictions by exploiting the high spatial density of observations TOMS provides.