The HadGEM1 model is the Met Office Hadley centre global environment model version 1. This version of the model includes a detailed representation of the atmosphere, land surface, ocean, and cryosphere. This dataset includes a control run and a number of climate change experiments. Typically, a control run is made to provide a "baseline" for comparison in climate change experiments. The control run uses constant values for the radiative forcing due to green house gases and anthropogenic aerosols appropriate to preindustrial conditions. The climate change experiments themselves are model runs where a scenario representing particular change in the greenhouse gas concentration over time is included.

You can browse to the related data production tool link below for more information about the model itself, and to the Numerical Simulation link below for details about how the model was set up for the simulation in this dataset.

The HadGEM1 data are held in 32-bit pp files.

Software is available to list, manipulate, view the HadGEM1 data. swapbytes can be used to byte swap pp files from the COAPEC dataset if neccessary. xconv provides an easy to use point and click interface to the data. convsh provides a subset of the functionality of xconv, but in a scriptable form, so it can be used to automate some common data processing tasks. Jeff Cole at CGAM Reading, who developed both xconv and convsh, provides some example uses of convsh.

A version of the Climate Data Analysis Tools (CDAT) has been produced which can read and manipulate pp data as if it were netcdf data. This can be downloaded from the NERC DataGrid site

A basic set of web pages describing the output variables available from the HadGEM1 control run dataset is also available from here. Details of the HadGEM1 model experiments are also available here. Please see Online References section below for additional references.

Recent Publications:

G.M. Martin, M.A. Ringer, V.D. Pope, A. Jones, C. Dearden and T.J. Hinton, 2006: The physical properties of the atmosphere in the new Hadley Centre Global Environmental Model, HadGEM1. Part 1: Model description and global climatology - J. Climate, Vol. 19, No. 7, pages 1274-1301 (1 April 2006)

M.A. Ringer, G.M. Martin, C.Z. Greeves, T.J. Hinton, P.M. James, V.D. Pope, A.A. Scaife, R.A. Stratton, P.M. Inness, J.M. Slingo, and G.-Y. Yang, 2006: The physical properties of the atmosphere in the new Hadley Centre Global Environmental Model, HadGEM1. Part 2: Aspects of variability and regional climate - J. Climate, Vol. 19, No. 7, pages 1302–1326 (1 April 2006)

T. C. Johns, C. F. Durman, H. T. Banks, M. J. Roberts, A. J. McLaren, J. K. Ridley, C. A. Senior, K. D. Williams, A. Jones, G. J. Rickard, S. Cusack, W. J. Ingram, M. Crucifix, D. M. H. Sexton, M. M. Joshi, B-W. Dong, H. Spencer, R. S. R. Hill, J. M. Gregory, A.B. Keen, A. K. Pardaens, J. A. Lowe, A. Bodas-Salcedo, S. Stark, and Y. Searl, 2006: The new Hadley Centre climate model HadGEM1: Evaluation of coupled simulations - J. Climate, Vol. 19, No. 7, pages 1327–1353 (1 April 2006)

• Hadley Center Technical Note 54 'Evaluation of the atmosphere preformance of HadGAM/GEM1' (Martin et al)
• Hadley Center Technical Note 55 'HadGEM1 - Model description and analysis of preliminary experiments for the IPCC Fourth Assessment Report' (Johns et al)

General queries about these pages and access to the data should be directed to the BADC support line. Your query should be answered within one working day. When follow-up work is required, the BADC support will carry out the work as quickly and efficiently as possible, and in any case, the user will be kept informed of progress.