Areas of expertise:

• ensemble storm surge forecasting
• observation error estimation
• generation of initial perturbations for ensemble forecasting

Current activities

For the main MOGREPS atmospheric ensemble system, Jonathan's work focuses on the sampling of initial condition uncertainty. In particular, he has developed a system to improve the horizontal and vertical distribution of spread, leading to improved probabilistic forecasts. This calculation requires reliable observation error estimates, with requirements that differ from standard data assimilation. A key part of the work involved developing a set of techniques to produce appropriate error estimates for satellite brightness temperature observations. Jonathan's other interests include perturbation structure and the potential uses of ensemble forecasts in Data Assimilation.

Jonathan was also responsible for developing an ensemble forecasting system for coastal storm surges. This work was undertaken in collaboration with Kevin Horsburgh at Proudman Oceanographic Laboratory, as part of a contract for the Environment Agency. By producing a storm surge forecast for each MOGREPS ensemble member, the surge ensemble propagates the consequences of uncertainty in surface wind and pressure through to uncertainty in water level, enabling better management of flood risk. Jonathan is supporting further work by Helen Titley to evaluate the benefits of extending the length of the surge ensemble forecasts to five days. He also supports work on ensemble forecasts of ocean waves being undertaken in Ocean Forecasting.

Jonathan has recently started a project to evaluate the potential benefits of combining output from multiple ensemble systems for medium range forecasts of precipitation. This is part of the international  THORPEX collaboration.

Career background

Jonathan joined the Met Office in 2006, after completing a DPhil at the  University of Oxford on the use of nudging and feature tracking techniques to evaluate climate model cloud. Prior to that, he spent two years working on graphics, audio and system device driver software for digital TV. Jonathan studied physics as an undergraduate, again at the University of Oxford.