eport Nataša Strelec Mahović Meteorological and Hydrological Service, Grič 3, Zagreb, Croatia EUMeTrain project Abstract The paper presents the concept of eport, an interface enabling the combined analysis of satellite data and products together with NWP model data and observations. eport is a part of training material developed by EUMeTrain project. Five available geographical panels enable a view from the North Pole down to the Southern Hemisphere with a 6-hourly time-step. INTRODUCTION eport (http://eumetrain.org/eport.html) is a product of EUMeTrain project (http://eumetrain.org), developed to allow the interactive combining of a range of EUMETSAT satellite images and satellite derived products with NWP model fields and observation data. The concept of eport is inherited from the long and successful practical application of SatRep analyses, used in the weather rooms around Europe. The word SatRep is actually a link-up of the two words: Satellite and Report. Originally the SatRep was a written report containing information about the cloud structures visible in the IR Meteosat image in combination with NWP models output and observations in terms of Conceptual Models. The method was first employed in the 1980s at the Austrian Meteorological Institute (ZAMG), developed by Dr. Veronika Zwatz-Meise. Further development took place with the co-operation of EUMETSAT, the Netherlands Meteorological Institute (KNMI) and the Finnish Meteorological Institute (FMI). In short, SatRep is a method of deriving a thorough view of the actual weather using satellite imagery and products combined with NWP model data and eport is an interface enabling such an analysis to broad users community. CONCEPTUAL MODELS Meteorologists try to recognize cloud patterns in satellite images by using the technique of conceptual models. Cloud tops and cloud patterns, seen by satellites, are a manifestation of physical processes in the troposphere. Conceptual models describe essential features of these physical processes through cloud phenomena, physical parameters, life cycles and weather events. Analyzing a satellite image in terms of conceptual models is the initial step to retrieve 3D or even 4D mental weather picture. Analysis of the weather situation by means of conceptual models provides a definition of the phenomenon in terms of features recognizable by observations, analysis or validated simulations; assessment of its life cycle in terms of appearance, size, intensity and accompanying weather; statement of the controlling physical processes which enables the understanding of the factors that determine the mode and rate of evolution of the phenomenon; specification of the key meteorological fields demonstrating the main processes; guidance for predicted meteorological conditions or situations using the diagnostic and prognostic fields that best discriminate development from non-development; guidance for predicting displacement and evolution. Conceptual models provide the meteorologist with a synthesis of all available information, giving him a full mental picture of the ongoing atmospheric process. This concept is a valuable supplement to numerical models for the nowcast time scale and may also serve as a tool for identifying errors in the numerical forecast or a possibility of filling in the gaps in the data. A collection of Conceptual Models
with all the mentioned elements can be found in SATMANU, a Manual of synoptic satellite meteorology (http://eumetrain.org/satmanu/satmanu/main.htm). GEOGRAPHICAL AREAS The basic idea of eport is to make the concept of combined satellite-nwp model analysis available to broad forecast community as well as all others interested in weather analysis. The interface allows the user to combine the satellite images with the whole range of NWP model fields and also satellite based products in different geographical areas. At the moment, eport provides five panels allowing a view from the North Pole all the way to the Southern hemisphere. Figure 1: Screenshot of the EUMeTrain home page (http://eumetrain.org) showing a drop-down menu of eport with a choice of the available panels in real-time and archive mode. Europe The European panel of eport is shown in Figure 2. To the right of the geographical area display there is a list of satellite images, coming from Meteosat geostationary satellites, as well as RGB composite images, NWC SAF, MPEF and other products, which can be displayed in the given area. By clicking on the box next to the name, a desired image is displayed. When clicking on the name itself, a pop-up window is opened, giving short information about the image or the product. Figure 2: Screenshot of the eport European panel showing the region covered by satellite and NWP data. In the example the IR 10.8 Meteosat image is overlaid by ECMWF field of AT 500 hpa isohypses.
The satellite images used in the European panel are produced by ZAMG. The list of the available ECMWF NWP model products, calculated by FMI, is displayed on the left of the panel. By clicking on the box next to the name, isolines of the desired parameter are displayed over the satellite image or product. Several NWP model parameters can be displayed over the image at the same time. Besides the view in the horizontal, eport also gives the possibility to inspect the vertical structure of the atmosphere, by offering a range of pre-calculated vertical cross-sections. By clicking on the box next to VCS, the lines showing available cross sections get displayed, as in Figure 3a. Choosing one of the cross-sections, by simple clicking on the line, opens a pop-up window with a cross-section. Basic parameter displayed in the cross-section is potential temperature and one or more of the offered parameters (temperature advection, relative humidity, vorticity advection, potential vorticity, divergence, omega, wind, and cloud cover) can be overlaid on the basic field (Figure 3b). a) b) Figure 3: a) Screenshot of the eport European panel with cross-section lines indicated. b) Pop-up window with a selected cross-section: the example shows isentropes overlaid by temperature advection isolines. South-Africa Satellite images (Meteosat, geostationary) and NWP model products covering the South-Africa panel are produced by the South-African Weather Service (SAWS). The list of satellite data and products (Figure 4) is much shorter than the one for the European panel, but still enabling the analysis. The NWP model fields come from the UKMO model. Figure 4: Screenshot of the eport South-African panel showing the region covered by satellite and NWP data. In the example Severe Storms RGB is displayed, revealing convection developing in the upper-most part of the panel.
Polar Satellite images and products providing coverage over the North Pole come from MetOp satellites and include AVHRR images, NWC SAF and OSI SAF products as well as Jason satellite and synop data (Figure 5). When opening the panel an image of Ice Concentration is displayed. The ECMWF NWP products that can be overlaid on the images are calculated by FMI. Figure 5: Screenshot of the eport Polar panel showing the region covered by satellite and NWP data. In the example AVHRR channel 4 image is overlaid by isotachs at 300 hpa showing the jet-stream. Middle-East Satellite images and NWP products covering the Middle-East (Figure 6) are a contribution of Turkish State Meteorological Service (TSMS). Figure 6: Screenshot of the eport Middle-East panel showing the region covered by satellite and NWP data. In the example the Airmass RGB combined with synop observations is shown.
Atlantic The Atlantic panel was originally developed to enable displaying of the meteorological data and NWP model parameters along the route of the German research vessel Polarstern (http://eumetrain.org/polarstern.html). The choice of NWP model parameters is much shorter than for the other panels (Figure 7), but the data are available every three hours. Figure 7: Screenshot of the eport Atlantic panel showing the region covered by satellite and NWP data. In the example OSI SAF product Sea Surface Temperature is shown together with ASCAT wave heights. ARCHIVE Besides the real-time images and products, eport enables the access to the archive, dating back to mid 2010. The archive data can give a quick overview of any interesting meteorological situation and are frequently used in different case-studies. WEATHER BRIEFINGS On a monthly basis the images and NWP model fields and the eport interface itself are used in the Monthly Weather Briefings, in which the current state of the atmosphere is discussed. The Briefings are performed over the internet by the EUMeTrain team members. They usually take from 30 to 45 minutes and are open to meteorologists, forecasters, students, researchers and anyone interested in weather. Participation in the Weather Briefings is free of any cost, however registration is needed. Registration can be done using the calendar at the EUMeTrain main page by clicking on the date of the briefing. Since 2012 the recordings of the Monthly Weather Briefings are available at http://eumetrain.org/briefings.html.
FUTURE DEVELOPMENTS eport interface was developed using Adobe Flash software. Due to recent extensive developments of portable media players and mobile computing devices, not supporting Flash-based applications, it became necessary to re-design eport in order to make it available also to the wider user s community. Future plans, therefore, include reprogramming the eport interface in HTML code. Along with sourcecode changes it is planned to enhance the frequency of the available satellite and NWP material to 3- horly time steps. The new version of eport should enable the possibility of fixing a desired combination of satellite image and NWP model field, which could then be viewed in previous time steps in order to follow the system development. ACKNOWLEDGEMENTS The EUMeTrain project owns a big gratitude to its former leader Jarno Schipper, who was a developer of eport as it is now. The concept of the combined analysis of satellite data and NWP model fields by means of conceptual models was developed by Dr. Veronika Zwatz-Meise, the first leader of the EUMeTrain project. Their energy and brilliant ideas kept the concept of eport alive and successful for years.