doi:10.21957/58njywom

COMPUTING

from Newsletter Number 122 – Winter 2009/10

Magics++ 2.8 – New developments in ECMWF’s meteorological graphics library

S. Siemen, S. Lamy-Thépaut Magics++ 2.8 – New developments in ECMWF’s meteorological graphics library

2 doi:10.21957/58njywom

Magics++ is the successor of Magics 6, ECMWF’s meteorological graphics library that has been used successfully at the Centre and in the Member States for more than 25 years. Magics++ has been written in C++, and takes advantage of the experience gained with its predecessor. More general information can be found in the article about Magics++ in ECMWF Newsletter No. 110, 36–41.

The newly released version 2.8 brings many new features and improvements to users. In the past year the library underwent much development for its integration into Metview 4, Web Re-Engineering Project (WREP) and the observation monitoring project. The aim in all these developments was to reach same look and feel for the visualisation between these services. Version 2.8 includes these changes along with many improvements and wishes from users outside the Centre. New features of version 2.8 include:

• Support of rotated grids (e.g. for HIRLAM models, see Figure 2)

• Introduction of Mercator projection

• Improvements in shading missing data

• Advanced symbol table mode for the support of ODB2

• Taylor diagrams (see Figure 3)

• Generalisation of the use of netCDF

• Improvement in the handling of satellites images

This article appeared in the Computing section of ECMWF Newsletter No. 122 – Winter 2009/10, pp. 32–33.

Magics++ 2.8 – New developments in ECMWF’s meteorological graphics libraryStephan Siemen, Sylvie Lamy-Thépaut

Figure 1 Magics++ also now supports KML output which can be visualised within Google Earth®. The KML output supports layers and animations.

S. Siemen, S. Lamy-Thépaut Magics++ 2.8 – New developments in ECMWF’s meteorological graphics library

doi:10.21957/58njywom 3

The new version also handles more complex layouts as used for the extreme forecast index (EFI) support plots, as shown in Figure 4. The Magics++ documentation has been updated and now includes more examples and information. The installation guide is also integrated within the main documentation, as are descriptions of how to set up an environ ment to develop and run Magics programs.

Tomeetthechallengeofthehigh-resolutiondata,Magics++offersawidevarietyofoptionsforcontouring from simple grid-shading to complex polygon shading, and also some tuning mechanisms tofindthebestcompromisebetweenhigh-qualityoutputandprocessingtime.

Magics6hasalwaysbeenabletoproducehighqualityoutput,andMagics++maintainsthistradition. Itdoesnotonlyproducehigh-qualityPS,EPSorPDFbutalsowithversion2.8moremodernweb-oriented formats such as PNG, SVG and KML/KMZ (for Google Earth®) as shown in Figure 1. To take full advantage of the latter format, Magics++ gathers some metadata about time or elevation from the data header, and integrates it in the KML output.

ThefamilyofuserinterfaceshasbeenextendedtoofferaPythoninterface.Thisfirstinterfaceissimilar to the procedural Fortran and C interfaces. First user feedback is very positive and a more object-oriented interface in conjunction with Metview is currently under consideration.

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Figure 2 Example of data on a rotated grid (Hirlam) plotted by Magics++.

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GEMS-RAQ Verification t+015 VT: Sunday 24 January 2010 15 UTCTaylor Diagram Surface Ozone

Figure 3 A Taylor diagram produced by Magics++.

S. Siemen, S. Lamy-Thépaut Magics++ 2.8 – New developments in ECMWF’s meteorological graphics library

4 doi:10.21957/58njywom

Magics++, which has been used operationally for the last four years to produce EPSgrams and EFI plots, has also been chosen to be the graphics engine for the Web Re-Engineering Project (WREP). This project provides services with features such as zooming or on-demand production of customised plots. In this context, a JavaScript library has been developed to allow the navigation of the maps and the possibility of clickable maps. An experimental OGC WMS (Web Map Service) as part of WREP is also using Magics++.Effortshavealsobeenputintothecreationofalibraryofmeteorologicalstylesforspecificparametersthatcombineefficiencyandreadabilitywithanewmodernlook.

ThesimilaritybetweenaMagMLStyleDescriptionandaMetviewVisualDefinitionwillallowauser to easily prepare a plot using Metview 4 and push it to the new Web catalogue.

The consolidation period of Magics++ will continue into 2010. In the coming months major software packagesatECMWF,suchasMetview,obstatandtheverificationpackage,willbeupdatedtouseMagics++ instead of Magics 6.

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Climate t+ [24-48h]Eps t+ [0-24h] Eps t+ [12-36h] Eps t+ [24-48h] Eps t+ [36-60h] Eps t+ [48-72h] Eps t+ [60-84h] Eps t+ [72-96h] Eps t+ [84-108h] Eps t+ [96-120h] Eps t+ [108-132h]

Climate t+ [24-48h]Eps t+ [0-24h] Eps t+ [12-36h] Eps t+ [24-48h] Eps t+ [36-60h] Eps t+ [48-72h] Eps t+ [60-84h] Eps t+ [72-96h] Eps t+ [84-108h] Eps t+ [96-120h] Eps t+ [108-132h]

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M-Climate: this stands for "Model Climate". It is afunction of lead time, date (+/- ~15 days), and modelversion. It is derived by rerunning a 5 memberensemble, over the last 18 years, once a week (450realisations). M-Climate is always from the samemodel version as the displayed EPS data. On thispage only the 24–48 h lead M-Climate is displayed.

24–48 h M-Climate extremaMin: Max:

Figure 4 Example of Magics++’s ability to lay out and generate graphs. The plot shows more detailed information to support the extreme forecast index (EFI).

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