Weather
Silvia Puca presents how H-SAF products can help in an early warning system.
Length: 22 minutes
Many severe meteorological events occurred in Europe during the last decade and caused casualties and damages to the historical heritage and natural environment. The European Civil Protection agencies, supported by meteorological and hydrological institutes, aim to assess risk scenarios, to monitor and supervise events and risk levels, providing early warning to National and local authorities. Near real time accurate estimations of hydrological variables such as precipitation and soil moisture are invaluable for the hydrological risk evaluation, enable them to issue early warnings and plan for disaster relief at the local level. Besides measurements of key hydrological variables by ground-based instruments, often affected by a limited spatial coverage, advanced satellite-based precipitation and soil moisture products developed within different international programs as H SAF, are available and accessible to users in near-real time. Severe meteorological events are selected in order to understand how the main satellite precipitation product characteristics, i.e. accuracy, spatial pattern and resolution, update frequency and latency, impact the efficiency of a hydro-meteorological early warning system at a local level in an operational framework.
Jan Kanak talks about comparing H-SAF products against ground truth data and shows some examples over Europe.
Length: 32 minutes
For proper usage of satellite products in meteorological applications it is necessary to take the set of skills which can be divided into technical, logistic and routine work with data, and final application of meteorological knowledge base by means of interpretation tools. Our lesson will provide step by step introduction to validation work with the H SAF precipitation products, introducing BUFR, GRIB and NETCFD decoding, reading and upscaling with the aim to put these various satellite products into common grid suitable for comparison against essential precipitation measurements considered as ground truth. Passing through the validation process and being aware of the accuracy of satellite products, we will show the applicability of these data using selected show cases over Central Europe. Case studies were prepared to demonstrate possibilities but also shortcomings of satellite data, which users need to take into account in practical usage. Because the proper preparation of satellite products is not important only for validation process itself, but also for practical applications, using show cases we will explain how to merge together various sources of precipitation information, e.g. irregular rain gauge point data, regular radar grid data, satellite scanned grids derived from microwave and infrared imagers. We will discuss the special treatment of continuous and discreet parameters like precipitation intensity or accumulated rain versus precipitation phase, quality index and surface type’s parameters to be up-scaled into common grid. Once up scaled data can be merged with the aim to obtain the most probable final values of instantaneous and accumulated precipitation fields. Final message of this training lesson addressed to meteorologists and hydrologists will be targeted to understanding that precipitation must be considered as stochastic parameter describing complex 3D processes in the atmosphere.
Leo Pio D'Adderio talks about the so-called Mediterranean hurricanes (Medicanes) or tropical-like cyclones (TLCs) as well as the severe precipitation events associated to atmospheric rivers.
Length: 34 minutes
The Mediterranean Sea is recognized as a climatic hotspot, often affected by severe weather events that are becoming more and more frequent in the last decades. Extreme events originating over the Mediterranean Sea and hitting the coast can have tremendous impact both from hydrological point of view as well as in terms of human and economic losses. Among these events, increasing attention has been recently devoted to the so-called Mediterranean hurricanes (Medicanes) or tropical-like cyclones (TLCs) as well as to the severe precipitation events associated to atmospheric rivers. This presentation shows the potentials of H SAF products together with measurements collected by active and passive microwave sensors onboard LEO satellites for the characterization and monitoring of the precipitation associated to severe weather events during their different evolution phases.
Marco Petracca talks about the validation of H-SAF precipitation products.
Length: 31 minutes
The H SAF Precipitation Product Validation Group (PPVG) annually analyses all the operational precipitation products released by the consortium in order to check the quality and evaluate their performance over time. The Quality Assessment (Q.A.) service is carried out by comparison with precipitation data used as reference. The comparison over the Europe is performed with radar and rain gauge data belonging to eight European countries: Belgium, Bulgaria, Germany, Italy, Hungary, Poland, Slovakia and Turkey. The methodology used to evaluate the quality of precipitation products is common to all member states through the use of a same algorithm (named Unique Common Code). Over African areas the comparison is performed with respect to the Dual-frequency Precipitation Radar (DPR) products of the Global Precipitation Measurement (GPM). Data used, methodology applied, and results obtained will be presented.
Davide Melfi presents a method that blends GEO and LEO precipitation products.
Length: 19 minutes
The main precipitation products developed worldwide are based on microwave (MW) radiometry Microwave (MW) radiation is the most effective for precipitation retrieval because of the direct interaction of radiation with the frozen and liquid hydrometeors within precipitating clouds as opposed to visible or infrared observations sensitive to the upper portion of the clouds. However, as microwave instruments are currently only available on-board satellites in Low Earth Orbit (LEO), they do not provide a continuous monitoring of rainfall over a given location. One methodology is to combine geostationary and low orbit satellite observations. This kind of multi-platform algorithm provides global precipitation estimation merging high quality, sparsely sampled data from low earth orbit satellites (e.g. Metop, NOAA series, DMSP, i.e. LEO/MS in general) with continuously sampled data from geostationary satellites (e.g. GEO/IR). The presentation will describe an example of such retrieval techniques used in HSAF and the future approach in combining such different sources of data.
Christian Massari shows that model recalibration or bias correction even with a few rain gauges can provide boost hydrological model performance and thus make satellite rainfall data a valid solution to obtain discharge.
Length: 41 minutes.
Flood modelling over data scarce regions is challenging. Satellite rainfall data offer a viable tool to force hydrological models and provide discharge prediction at ungauged sites. However, being an indirect type of measurements, satellite rainfall observations can be subjected to significant bias and might be suboptimal over mountainous terrain. Here we show that model recalibration or bias correction even with a few rain gauges can provide boost hydrological model performance and thus make satellite rainfall data a valid solution to obtain discharge. In the presentation we will describe the theoretical background for using satellite rainfall products in flood prediction and provide some tips to enhance their performance in riverine flood modelling.
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Giulia Panegrossi presents the challenges and recent advancements in satellite-based snowfall quantification and global monitoring.
Length: 37 minutes
Snow plays an important role in the Earth energy exchange processes, and is a fundamental element of the water cycle. The use of satellites for snowfall monitoring and quantification and for retrieving snow cover properties and variability is necessary to globally quantify water resources. Satellite-based snowfall detection and surface snowfall rate estimation are becoming an increasingly popular topic within both the hydrological scientific community and operational services. Recent studies have evidenced how space borne multi-channel microwave (MW) radiometer measurements respond to both snowfall and snow cover properties. In this presentation the challenges and recent advancements in satellite-based snowfall quantification and global monitoring will be discussed, and the retrieval strategies that are being adopted within the EUMETSAT H SAF to improve detection and quantification of snowfall, with particular focus on higher latitudes, will be presented.
Oliver Sievers and Jens Kieser report from the MOSAiC expedition of the German vessel Polarstern in the Arctic Sea.
Meteorologists and weather technicans from the German Meteorological Service (DWD) attended the entire MOSAiC expedition, the largest-scale Central Arctic research expedition of all time. They were responsible for permanent weather observations and daily meteorological forecasts for scientists, ship master and officers, as well as helicopter pilots. Our presentation will report about personal experiences of a meteorologist on board of the research icebreaker POLARSTERN, with the focus on the daily work of the forecaster and the importance of using satellite images in Polar Regions.
Yulia Mishenina presents the results of studies of the characteristics of snow cover for the territories of Western and Eastern Siberia.
The report presents the results of studies of the characteristics of snow cover for the territories of Western and Eastern Siberia. The research period is from 1976 to 2020.
The report describes the duration of persistent snow cover, the time intervals between the first snowfall and stable snow cover and between the destruction and disappearance, a number of characteristics of the snow cover: duration of occurrence, thickness and water content.
Ákos Horvath talks about ice formation on Lake Balaton and the dependence from local wind and weather.
Lake Balaton is the largest lake in the Carpathian Basin. The shallow lake (with 3.5 m mean depth) responds to the weather rapidly: in hot summers the water temperature increases above 25 °C, and at colder winters thick ice (20-40 cm) appears on the lake surface. The formation of the ice depends very much on the weather. Glassy ice forms when after a cold front passage in the night the wind and waves calm down and the previously mixed up and supercooled water freezes rapidly. During longer cold and windy weather period, ice appears in forms of ice floes, frozen to each other. This presentation tries to give an overview of the metamorphosis and special dynamic of the Balaton ice.
Michael Winkler puts heavily burdened roofs in the spotlight by presenting recent efforts in updating the Austrian snow load standard and showing an actual example of snow load monitoring and hazard management.
Snowy winters lead to heavy snow loads on buildings and constructions. Surprisingly often, the snow load assessment basis of international and national standards are regionally reached or exceeded. Damages or even collapses do occur, cause expenses and threaten human lives. However, extreme snow loads only rarely are considered as natural hazards. This talk puts heavily burdened roofs in the spotlight by presenting recent efforts in updating the Austrian snow load standard and showing an actual example of snow load monitoring and hazard management.
Michael Rothleitner discusses economic and ecological aspects of winter tourism in the Alpine region.
At the beginning, the economic interrelationships of winter tourism in the Alpine region, Austria and finally Tyrol are highlighted. The dependence of value creation on a reliable snow situation in winter therefore forces snow management, the economic and above all ecological tasks of which will be presented. The participants will get to know the essential problems and the existing approaches to solving them.