Jonny Williams 

Data from some climate model simulations is in a 360 days per year format, that is, every month is 30 days long. The main reason for this is analytical convenience in creating seasonal, annual and multi-annual means which are an integral part of climate model development and evaluation. This work illustrates a method to convert daily-mean, 360-day calendar climate model data into 'real', Gregorian calendar format. The method includes randomisation of the interpolation dates to avoid spurious artefacts in the output data, support for leap years and the ability to be run in in parallel so that multiple variables and years can be processed simultaneously. Future work to generalise this software to allow for sub-daily output frequency is encouraged and it is hoped that this work facilitates easier inter-model comparisons and knowledge transfer.