The full title of the CONVEX project is "Using observational evidence and process understanding to improve predictions of extreme rainfall change".
The CONVEX project is investigating deficiencies in the simulation of extreme rainfall by regional climate models (RCMs) with the aim of providing a better understanding of the atmospheric processes that produce these events. This is essential for improved model predictions of extreme rainfall change under global warming, and will help to inform future adaptation strategies for flood risk management. It will also provide the improved understanding of processes that is vital for future climate model development.
The main themes of the project include the analysis of observed historical datasets to better understand the characteristics and causes of extreme rainfall as well as to assess the deficiencies of climate models. In collaboration with the UK Meteorological Office, by running an RCM at a higher resolution than has previously been undertaken, the project will assess the benefit gained from increasing climate model resolution and investigate the development of a method by which such improvements can be reproduced using statistical downscaling methods.
By running the Met Office's forecast model (1.5 km resolution) as part of a climate change experiment over the southern half of the UK we have identified improvements in the simulation of rainfall compared with a coarser (12 km) model. At the 1.5 km resolution the model can dynamically represent convection in the atmosphere. We have identified that the greatest added value in running high resolution simulations is for summer extreme hourly rainfall. In terms of future projections under greenhouse forcing the 1.5 km model identifies an intensification of summer hourly extremes which are not projected at the coarser resolution. The project is continuing to explore the drivers of these rainfall extremes.
Projected increases in summer and winter UK sub-daily precipitation extremes from high-resolution regional climate models Chan S.C., Kendon, E.J., Fowler, H.J., Blenkinsop, S. and Roberts, N.M. 2014. Environmental Research Letters 9 084019 doi:10.1088/1748-9326/9/8/084019.
Heavier summer downpours with climate change revealed by weather forecast resolution model
Kendon, E.J., Roberts, N.M., Fowler, H.J., Roberts, M.J., Chan, S.C. and Senior, C.A. 2014. Nature Climate Change 4, 570–576. DOI: 10.1038/nclimate2258.
The Value of High-Resolution Met Office Regional Climate Models in the Simulation of Multihourly Precipitation Extremes
Chan, S.C., Kendon, E.J., Fowler, H.J., Blenkinsop, S., Roberts, N.M. and Ferro, C.A.T. 1994. Journal of Climate, 27, 6155–6174. DOI: http://dx.doi.org/10.1175/JCLI-D-13-00723.1
Does increasing the spatial resolution of a regional climate model improve the simulated daily precipitation?
Chan S.C., Kendon E.J., Fowler H.J., Blenkinsop S., Ferro C.A.T., Stephenson D.B.
Climate Dynamics, 2013, 41 (5–6), 1475–1495. DOI: http://dx.doi.org/10.1007/s00382-012-1568-9.
Realism of rainfall in a very high resolution regional climate model
Kendon E.J., Roberts N.M., Senior C.A., Roberts M.J.
Journal of Climate, 25, 5791–5806. 2012. DOI: http://dx.doi.org/10.1175/JCLI-D-11-00562.1
Principal Investigator: Professor Hayley Fowler, Newcastle University
Dr Stephen Blenkinsop, Newcastle University
Professor David Stephenson, University of Exeter
Dr Chris Ferro, University of Exeter
Dr Elizabeth Kendon (UK Met Office Hadley Centre)
Richard Jones (UK Met Office Hadley Centre)
Dr Steven Chan, Newcastle University
Nigel Roberts (UK Met Office Joint Centre for Mesoscale Meteorology)