Introduction

Tools required

For this workshop, several specialised tools (computer programs) will be required to process S2S data. These include tools to:

1. Download S2S data from the ECMWF website using the ECMWF Web API through MARS platform.
2. Post process GRIB data to netCDF (when necessary), using ECMWF GRIB-API.
3. Plot and visualise data using Python's packages matplotlib and basemap.

Optional tools

1. Process data such as to subset and average the data before plotting/visualisation using Climate Data Operator, CDO.
2. To visualise data on-the-fly using Panoply

Installing the tools above can be tedious and time-consuming and most of all it requires you to run a Linux-based system. If your laptop is running a Linux Operating System (OS) and you are familiar with installing programs/packages on Linux, you may proceed to do so by following the instructions on the links provided above.

Otherwise, we have prepared a Virtual Machine (VM), which is a Linux image (Guest OS) with all the required programs installed, and the VM will be installed on your laptop's Windows OS (Host OS). The following section will take you through the steps to set up the VM on your laptop. Once completed, all the tools above will be ready to be used for the workshop, without you having to install the different libraries/packages required one by one.

Acknowledgement: The following steps have been adapted from a tutorial by David Hein from the UK MetOffice for the 3rd SEACAM Workshop, August 2013.

Step 1 - Download and install Oracle VM VirtualBox

a. Download the VirtualBox software from: https://www.virtualbox.org/wiki/Downloads. Select the right version for your laptop's OS, i.e. if you are running the Windows OS, choose the version "Windows hosts".
b. Once download is complete, click on the installation file and follow through the installation wizard until completion.
c. Once installed, open the VirtualBox program. It should look like the sreenshot below, without the "Antix 32GB" entry on the left-side. But this is what we want to achieve at the end.

Step 2 - Import the pre-configured VM ("Appliance")

This step involves copying a large (4 GB) 'appliance' file onto your laptop. It can be downloaded from online, or obtained later during the workshop. If you are struggling with downloading the file yourself, please wait for the workshop.

a. Download the pre-configured VM/appliance (WARNING 4GB FILESIZE). It comes installed with all the necessary programs. Save it on the desktop of your laptop (or elsewhere you can remember). NOTE: this file is about 4GB and if your internet connection would not allow you to do so easily, we will provided the file during the workshop and install it then.
b. On the VirtualBox interface, click "File" at the top-left menu, and select "Import Appliance..." This is shown below:

c. Click on the "browse" button on the right to select the downloaded VM that was saved earlier. Click "Next" and in the following screen, without changing any settings, click "Import".

d. The importing process will take not more than 15 minutes to complete. If there are no errors reported the VM is ready to be used. Follow the next step to create a shared folder on your laptop's (C:) drive to be accessible from the VM. Your VirtualBox should now list the Antrix 32GB on the left side of the screen as below:

e. Next step