Seasonality often accounts for the major part of quarterly or monthly movements in detrended macro-economic time series. In addition, business cycle nonlinearity is a prominent feature of many such series too. A forecaster can nowadays consider a wide variety of time series models which describe seasonal variation and regime-switching behaviour. In this paper we examine the forecasting performa...

In this paper a class of seasonal space-time models is introduced for general lattice systems. Covariance properties of spatial rst-order models, including stationarity conditions, are studied. Procedures for examining spatial independence and symmetry of the models are developed. Estimation approaches in time series analysis are adopted, and forecasting techniques using the seasonal space-time...

Seasonal forecasts run by the Eta Model over South America were evaluated with respect to precipitation predictability at different time scales, seasonal, monthly and weekly for one-year period runs. The model domain was configured over most of South America in 40 km horizontal resolution and 38 layers. The lateral boundary conditions were taken from CPTEC GCM forecasts at T62L28. The sea surfa...

The long-term goals of this project, which is being pursued in collaboration with R. L. Elsberry and M. A. Boothe, are to improve not only the quantitative accuracy of official tropical cyclone (TC) track forecasts, but also the qualitative meteorological utility of those forecasts. Needed improvements in the accuracy of official TC track forecasts include: (i) reducing the severity and frequen...

Integrated, interdisciplinary crop performance forecasting systems, linked with appropriate decision and discussion support tools, could substantially improve operational decision making in agricultural management. Recent developments in connecting numerical weather prediction models and general circulation models with quantitative crop growth models offer the potential for development of integ...