Humphrey leads research into formulation and applications of convective-scale versions of the Unified Model.
Humphrey manages the Mesoscale Modelling group at JCMM. The main activities of this group are to continue to develop km scale versions of the Unified Model. Current areas of work in the group are continuing development of the physics in km scale models (particularly convection, turbulence/mixing schemes), development of convective scale ensemble systems (in collaboration with the Ensembles group in Exeter) and evaluation of the performance of the km scale models for various phenomena of interest (e.g. convection and convective initiation).
The Mesoscale Modelling group works closely with the JCMM Convective-scale Data Assimilation and Nowcasting group (managed by Susan Ballard) which is aiming to produce a km-scale NWP based nowcasting system.
Humphrey's personal interests lie in the areas of orographic rainfall (particularly the seeder-feeder effect), convection and mesoscale structure in cyclones.
An important aspect of Humphrey's work is to facilitate collaboration with colleagues in academia in particular with the University of Reading Meteorology department where JCMM is based.
Humphrey's first degree was in Physics (Bristol) followed by a PhD in low temperature physics, specifically superconductivity (Cambridge). He carried out post-doctoral work on high-temperature superconductors and also worked for a couple of years at Culham Laboratory on the tokamak fusion programme.
Humphrey joined the Met Office (JCMM) in 1995 and worked initially in the Weather Systems group with Sid Clough. In early 1997 the group was involved with the Fronts and Atlantic Storm tracks Experiment (FASTEX) and much of his work was involved in mesoscale modelling of cases from this. Particular areas of interest were the role of microphysical processes in cyclone development and system relative analysis.
In 1998 Humphrey moved into the JCMM Mesoscale Modelling group with Peter Clark, but continued to work on FASTEX related modelling for a while. In late 1999 he started work running the non-hydrostatic prototype of the Unified Model at higher resolutions than 12 km (then the highest in the operational system) which, very quickly, showed encouraging results (initially for FASTEX cases). This work led to Humphrey starting the High Resolution Trial Model (HRTM) project in 2002 ,which established many aspects of the optimal configuration of the Unified Model at 4 km and 1 km resolutions, and included systematic trials to ascertain both the benefits and the problems with these models. This work led directly to the implementation of the UK 4 km model in the operational system in 2005 and the 1.5 km model in 2009.