Neill is a scientist working on the development of the global ensemble prediction system.
This system is used to estimate the uncertainty in the weather forecast. It is also used in the process of data assimilation, which looks to improve weather forecasts by improving techniques for assimilating observations.
Recent work has focused on developing an ensemble of data assimilations based on 4DEnVar. This system is based on the four-dimensional variational data assimilation method used operationally for assimilating observations. However, it does not require the expensive tangent-linear model which makes it very useful for ensemble generation. Being close in method to the data assimilation system should mean it is effective at simulating the uncertainties in the data assimilation, which will improve the weather forecast.
Additionally, Neill's work has involved understanding the use of ensemble information within the data assimilation, and some idealised work on the diagnosis of model errors.
Neill's background lies in the generation of initial-condition perturbations for ensemble forecasts. Ensemble forecasts are produced by running the forecast model a number of times, with slightly different starting conditions and small perturbations to the forecast model. Neill's main activity in this area is to develop the capability of the new 4DEnVar system to generate initial conditions for ensemble forecasts. In particular, he is looking at how to inflate the ensemble perturbations so that they fully cover the range of possible forecast outcomes.
Neill has also worked on the verification of forecasts, which involves comparing past forecasts with observations to assess how skilful the forecasts were. Neill's work covered a number of novel verification methods, particularly for probabilistic forecasts. Neill provides support for the ensemble prediction system used by other national Met services through the Unified Model collaboration.
Neill started work for the Met Office in 2001, looking at the precipitation nowcasting system. He was heavily involved in developing Nowcasting, the ensemble prediction system for precipitation nowcasts. In 2003, Neill moved to join ensemble forecasting research. Since 2011 Neill has worked as a scientific manager, initially of the ensemble data assimilation group.
Prior to joining the Met Office, Neill completed a PhD in Physics at the University of Warwick. This work was on the role of noise in optimisation problems and in diffusion-limited aggregation.
Last updated: 1 June 2016