UKCA & UMUI Tutorials: Things to know before you start

Back to UKCA & UMUI Tutorials

You should not use the UKCA Tutoral jobs for scientific studies. They are designed to be used as training aids.

PUMA and HECToR/MONsooN

Before you begin this tutorial you should first get a PUMA and a HECToR or MONSooN account as the UKCA Tutorial is based around jobs which run on these supercomputers, using PUMA to submit them.

Further information about how to apply for these account can be found on the Getting Started with UKCA page.

This tutorial can be run on both HECToR and MONSooN. In the UMUI Search → Filter... for:

• The HECToR experiment is xxxx
• The MONSooN experiment is xxxx

UM Training and the FCM Tutorial

There is some information about the UM here:

http://cms.ncas.ac.uk/wiki/UmTraining

You must also have completed the NCAS-CMS UM FCM Tutorial. This tutorial assumes that you have had some experience in using the UM, and know how to copy an existing job to your account and run it.

If you have never used the UM before you should also view the NCAS-CMS UM Training pages, which has a basic introduction to the UMUI.

You will also find the NCAS-CMS pages very useful: cms.ncas.ac.uk.

Archiving

By default the UKCA Tutorial jobs are set to archive data to

/work/n02/n02/userid/um/jobid/archive/

on HECToR, and to

/nerc/ukca/userid/jobid/

on MONSooN (if you are not in the ukca project group you will need to set your project group here).

This will be known as your archive directory throughout the rest of this tutorial.

Note: If you have made some changes to a job and resubmit it, the files in your archive directory will not be over-written. You will need to either delete these files, or move this directory before starting your job again, e.g.

On HECToR cd into your

/work/n02/n02/userid/um/jobid/

directory and do

mv archive archive.old

and on MONSooN cd into your

/nerc/group/userid/

and do

mv jobid jobid.old

etc. This now means that when your job runs new output will be copied to the archive directory, which is created by the UM if it does not exist.

Archiving is controlled in the UMUI in the Model Selection → Post Processing → Main Switch + General Questions panel.

Structure

UKCA is not one particular chemistry scheme, but is in fact a framework for adding a chemistry scheme to the UM. Although in this tutorial you will adapt an exisiting scheme, you could extend this to replacing all tracers and reactions and add in a completely different scheme.

UKCA Chemistry Tutorials

These Tutorials are actually one large problem which someone who uses UKCA may be required to do: add some tracers, reactions, deposition, and diagnostics. To make this problem more manageable it has broken down into a series of small tasks which you will be asked to complete. Each Tutorial explains how to make the necessary changes (in general terms), and then you will be asked to make the required changes to your UKCA job.

To accompany each Task which requires UMUI or UKCA code changes, there are worked solutions (held in the same UMUI Experiment as the original Tutorial Base Job) along with sample output and a wiki page detailing the changes in full. If at any point you have difficulty completing one of the Tasks you can take a copy of the worked solution job and carry on from there.

Model Configuration

The UKCA Tutorial job is at UM version 8.2 job using a Global Atmosphere 4.0 atmosphere-only configuration. It has a resolution of N96L85 (1.875 degrees by 1.25 degrees, with 85 vertical levels up to 85km).

While you may be interested in using UKCA at a different UM version, many aspects of this tutorial will be directly transferable. For instance, many of the UMUI panels and much of the UKCA source code are the same at UM7.3 as at UM8.2.

Further Information

More information on UKCA can be found by browsing this wiki. More detailed information on UKCA can also be found in the UKCA documentation paper for vn8.2 of the MetUM .

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Written by Luke Abraham 2013