This paper has been converted to HTML for the CD-ROM. The original word document is available here.
Jean Coiffier
Forecast Laboratory, SCEM/Prévi, Météo-France,
42 Av. G. Coriolis - 31000 TOULOUSE Cedex (France)
Estelle Magnin
Clairis-Technologies, 7 Av. Albert-Durand,
BP 69 - 31703 BLAGNAC Cedex (France)
1 - Introduction
Continuous training of the forecasters has become a necessity for Meteorological Services owing to the rapid development of the modern tools now available to observe the atmosphere and to visualize forecasts issued from numerical models. Moreover scientists have been proposing detailed conceptual models describing the origin and the evolution of the atmospheric perturbations. This renewal of the dynamic meteorology prevailed on Météo-France to propose new graphical documents with symbols referring to conceptual models in order to summarize the main synoptic features of the analyzed and forecast meteorological situations The realization of a CAL (Computed Aided Learning) devoted to this new way of working, has been undertaking with the help of Clairis-Technologies, which benefits from the experience gained in the framework of the Euromet project. It is expected that such a training course directly available on the forecaster’s working screen will allows to concern a large number of forecasters and to illustrate the characteristics of the conceptual models by number of charts and images similar to those they are accustomed to.
2 - Operational meteorological forecasting at Météo-France
Meteorological forecasts and various associated products are elaborated at Météo-France by forecasters working in various centres organized with a three-level hierarchy.
The central forecast office, located in Toulouse, interprets the outputs from the numerical models ; it defines the synoptic characteristics and the associated phenomena of the expected evolution of the atmosphere.
Seven regional forecast offices add details about chronology and geographical location of the weather phenomena deduced from the synoptic pattern inside their own responsibility area.
Finally, about one hundredth local forecast offices located in the French administrative departments prepare the final forecasts devoted to local end users.
This organization emphasizes the important part which is given to the man in the forecast process. Nevertheless it also implies a clear definition of the complementary tasks which have to be done at each level and an efficient way to communicate the results of their technical expertise to the other levels. A lot of the most relevant charts issued from the various numerical models are transmitted toward all the forecast offices and there is a need for a document, elaborated at the central forecast office in order to synthesize the synoptic evolution of the atmosphere.
3 - Anasyg/Presyg : New meteorological documents
Traditionally, technical weather forecasts for the synoptic scales have been consisting in surface pressure charts with superimposed contours of the frontal discontinuities at the surface. Nevertheless such a simple description, inherited from a knowledge of the atmosphere by using the synoptic observation network, does not reflect the diversity of all the atmospheric structures. Nowadays the availability of new observing tools like radar networks or satellite images as well as realistic simulations provided by numerical models allow to have a better understanding of the meteorological phenomena. The complexity of the three-dimensional structure of the atmosphere can be investigated by means of powerful visualization software available on workstations or PCs. This is the reason why Météo-France, following guidelines proposed by Joly (1993), decided to introduce a new graphical document named Anasyg/Presyg (Graphical SYnoptic ANAlysis or PREdiction), elaborated by the central forecast office, in order to summarize the main synoptic features characterizing the present state and the evolution of the atmosphere.
4 - Need for a large training action
The correct use of a new document for transferring the synoptic forecaster’s expertise needs a good knowledge about the significance of the various symbols and the conceptual models they are referring to. The document Anasyg/Presyg synthesizes the synoptic evolution of the atmosphere and has to be understood very well by all the people involved in the forecast process. To take up this challenge Météo-France has been undertaking a very large training action covering a three-year period and involving about 300 people. This action began in March 1999 with a course devoted to the « training of trainers » aiming to define the content of the training and to gather the various pedagogical aids. Among them the electronic course, or CAL, devoted to the Anasyg/Presyg represents a masterpiece of the necessary pedagogical material to insure a large-scale training action.
5 - The choice for a CAL
An electronic course or CAL has been chosen as a basic tool especially designed for helping forecasters to assimilate the new concepts and correctly interpret the new documents Anasyg/Presyg, issued from the central forecast office, for several reasons.
It can be easily remotely accessed within the working environment of the forecaster by using Intranet or locally by means of CD-ROM copies. It can be used first as a self-learning tool by every forecaster to complement formal presentations and also as a « handbook » always available to recover the characteristics of a typical weather situation.
It allows to incorporate various example by using images or sequences of images taken from the actual forecaster’s environment, with the possibility of animation and superimposition.
It can be continuously updated and improved by taking into account the remarks formulated by the forecasters.
It contains a lot of graphical materials which can be easily extracted in order to make pedagogical aids usable in another context.
6 - General organization of the course
This course contains about thirty modules : after a short introduction explaining the reasons for a new document to summarize the synoptic evolution of the atmosphere, a first part is devoted to the presentation of the modern bases of the dynamic meteorology with special emphasis on the leading role of the potential vorticity field. A second part presents the characteristics of the most common conceptual models and the means to recognize them with help of satellite images and model fields and finally a third part proposes a rationale methodology to elaborate the Anasyg/Presyg as well as the ways to interpret the various symbolic representations in terms of characteristic weather.
Figure 1 : Example of a page describing a possible evolution of an ana cold front and the specialized buttons used to navigate within the course.
Each module opens with a summary allowing to directly reach a specified section while navigation buttons (Fig.1) allow to progress sequentially throughout the module. Each module can be consulted separately but several parts of the modules can be reached by keywords contained in an index always accessible. A glossary of about 400 entries explains the most current terms encountered in dynamic and synoptic meteorology. On-line help is also available in order to assist the learner in using efficiently the various buttons and icons. Finally a newsbox allows to inform the users about the modifications which could be introduced in this course
7 - Technical realization
The realization of this CAL is being carried out by Clairis-Technologies, which adopted the same development principle as for the Euromet project, particularly as regards to the separation between the contents and the navigation bar, and the principle of macro-commands.
The formalization of the so-called dynamic version 4 of HTML at the start of the project, raised the issue of the changeover to this version. In July 1998, interpretation of the dynamic HTML by the navigators was not stabilized ; there were a number of differences in interpretation of the standard between the navigators. Some of these still subsist. In addition the new functions proposed by the HTML were not fundamental for use by this CAL, and could be developed in Java. Anasyg/Presyg CAL therefore uses HTML version 3.2.
The differences between the navigators illustrated on the dynamic HTML are present on other functions in the Windows environment. It becomes increasingly difficult to develop an application that can guarantee compatibility, not only between navigators but also between versions of the same navigator, under Windows. Netscape Gold under Windows NT4, for example and Internet Explorer 4 have a different interpretations of the flags for breaking down (particularly for bold type) ; this leads to differences in the text display. The expansion of the Web and the associated issues at stake have completely changed the nature of the initial function, which was to provide access to information, independently of the user station
At the same time, the increased security in navigators with respect to Java applets, already observed on the Euromet project, requires the installation of a HTTP server on the user station for local operation. This involves the creation of an appropriate installer for the local implementation of the CAL from a CD-ROM.
As regards to the development of graphics and animation in particular, the VRML, tested on the Euromet project has not significantly changed and still has the same limits. However, attractive plug-ins are now becoming available : World View 2.0 by Intervista and Contact 4.0 by Blaxxun Interactive.
At the same time, another single viewpoint animation standard has gained recognition : Flash 3 by Macromedia. This tool represents a true revolution, as it can be used to create vectorial animation, which is not memory consuming. It now forms part of the plug-ins included by default in the latest versions of Internet Explorer and Netscape. Until now, it was used to generate animated GIF on the CAL, but the use of its native format, which is superior in terms of graphic rendering, is now being considered.
8 - Present status and perspectives
The first modules of this CAL began to be used in the framework of the first course devoted to the trainers and a few lessons can be learnt from this experience. The possibility for the teacher to comment the various charts and animated images projected on the screen of the classroom is fully appreciated while reading the accompanying text - more adapted for the self-learning - proved not to be well adapted for such a presentation. The first version in French language is expected to be completed by the end of year 1999 so that its extended use in the framework of the large-scale training action will take place during year 2000.
A translation of this course in English is already planned in order to allow foreign meteorologists to be aware of the new documents issued by the French national meteorological center which will be transmitted abroad in the framework of bilateral or regional agreements.
Thanks to the possibility to extract charts and images, an important part of the graphical material could be reused in order to prepare presentations more adapted for projections in a classroom. Another improvement for the future would consist in replacing the written text by numerized recorded voice allowing to better concentrate the attention of the learners on the graphical display.
References :
Joly A, 1993. L’évolution de la météorologie dynamique - Atelier « Evolution de la prévision centrale », Météo-France, Internal document.