Future weather@home applications will only run on a single operating system: Windows, Linux or Mac – here’s why…

As we continue developing new weather@home applications – regional climate models that look at particular extreme weather events – we will be moving to a policy of picking a single operating system for each, rather than developing all models for all operating systems. By doing this, we aim to improve both the reliability and the science of climateprediction.net.

Recent new versions of all 3 operating systems have had backwards compatibility problems which have led to a noticeable decrease in the reliability of the models you have been running for us. By concentrating on a single operating system for each application, we can increase reliability whilst maintaining the current level of effort we’re putting into the development of each application.

Different operating systems produce very slightly different results when running identical models. The differences are really very small, but since we’re often making close call distinctions in very large ensembles of models, these small differences can be significant. If there are different numbers of models run on each operating system within two ensembles that we want to compare – for example, “natural” and “anthropogenic” ensembles for weather event attribution studies – this might introduce a subtle bias to our results. We will produce more robust science if all the models in an ensemble are run using the same operating system.

We will endeavour to match the size of the ensemble to the operating system, given there are many more Windows machines running models than either Mac or Linux, but if you have a Mac or Linux machine, please do add it to the project!

We hope this doesn’t cause too much inconvenience, and many thanks again for your support for the project.

The CPDN team.