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Meteorological hazard maps are one of the components of the IT System for Country Protection against extreme hazards (ISOK) created by a consortium of Polish institutions, including the Institute of Meteorology and Water Management – National Research Institute. These maps present meteorological phenomena such as: temperature extremes, heavy and flood-producing rainfall, strong winds, intensive snowfall, fogs, glaze, rime and thunderstorms with hail. These elements were chosen arbitrarily due to recorded or estimated losses. The main aim of the maps is to present visualization methods of hazard forecast with consideration of climatological (historical) background. To identify areas especially exposed to the above meteorological hazards, extensive climatological analyses were performed, based on long-term daily data (mainly the 1951-2010 period). The main component of the warning system is a set of prediction maps created automatically on the basis of scientific algorithms that provide the probability of the occurrence of particular phenomena, or the conditions favourable for them. The algorithms’ structure, based on information about physical processes in the atmosphere, as well as detailed climatological analysis, enables the reclassification of the forecast values – predicted by the ALADIN mesoscale atmospheric model – into four groups of any hazard at the gridded points. Finally, the information will be interpolated and will result in the production of maps of spatial distribution presenting the objective probability of a particular hazard, i.e. its actual risk. Results of historical analysis are to be presented for the public by a number of climatological maps, and accompanied by additional fact sheets to provide society with an actual view of the spatial distribution of the distinguished weather phenomena, and the interrelated risks.
The occurrence of forest fires is frequent phenomenon in Greece, especially during the warmest period of the year, the summer. Timely and reliable estimation of the meteorological risk for their onset is of crucial importance for their prevention. Thus, the purpose of our current work was firstly the estimation of the values of a suitable relevant index for Greece, meteorological forest fire risk index (MKs,t), derived from actual air temperature (T) and relative humidity data (RH) as well as from regressed T and RH, in a mountainous region (MR) of Nafpaktia, Greece, for the most dangerous period of the year (July-August) and day (11:00 h -16:00 h), for five successive years (2006-2010) and secondly the comparison of the two ways of MKs,t values estimation (from actual and regressed T and RH), based on MKs,t classes. Regressed T and RH data were estimated with the aid of simple linear regression models from T and RH data, respectively, of an urban region, 175 Km away from MR, taking into account firstly the warmest (2007) and the coldest (2006) year of the examined year period. It was confirmed that MKs,t values (based on regressed T and RH data) coincided in their classification to the respective ones resulted from actual T and RH data, that is, there was absolute success (100%). Using simple linear regression lines and applying them to estimate separately T and RH at MR, for the most dangerous period of year and day concerning the whole examined year period, it was found that almost all the estimated MKs,t values coincided, regarding their classification, with those estimated from actual T and RH data (97% success), which was considered very satisfactory. Therefore, our research methodology contributes a new perspective to a reliable estimation of MKs,t from remote T and RH data using simple statistical models.
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