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A raster-based glacier sub-model was successfully introduced in the distributed hydrological model FEST-WB to simulate the water balance and surface runoff of large Alpine catchments. The glacier model is based on temperature-index approach for melt, on linear reservoir for melt water propagation into the ice and on mass balance for accumulation; the initialization of the volume of ice on the basin was based on a formulation depending on surface topography. The model was first tested on a sub-basin of the Rhone basin (Switzerland), which is for 62% glaciated; the calibration and validation were based on comparison between simulated and observed discharge from 1999 to 2008. The model proved to be suitable to simulate the typical discharge seasonality of a heavily glaciated basin. The performance of the model was also tested by simulating discharge in the whole Swiss Rhone basin, in which glaciers contribution is not negligible, in fact, in summer, about the 40% of the discharge is due to glacier melt. The model allowed to take into account the volume of water coming from glaciers melt and its simple structure is suitable for analysis of the effects of climate change on hydrological regime of high mountain basins, with available meteorological forcing from current RCM. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Soil moisture is an important component of the hydrological cycle. In the framework of modern flood warning systems, the knowledge of soil moisture is crucial, due to the influence on the soil response in terms of infiltration-runoff. Precipitation-runoff processes, in fact, are related to catchment's hydrological conditions before the precipitation. Thus, an estimation of these conditions is of significant importance to improve the reliability of flood warning systems. Combining such information with other weather-related satellite products (i.e. rain rate estimation) might represent a useful exercise in order to improve our capability to handle (and possibly mitigate or prevent) hydro-geological hazards. Remote sensing, in the last few years, has supported several techniques for soil moisture/wetness monitoring. Most of the satellite-based techniques use microwave data, thanks to the all-weather and all-time capability of these data, as well as to their high sensitivity to water content in the soil. On the other hand, microwave data are unfortunately highly affected by the presence of surface roughness or vegetation coverage within the instantaneous satellite field of view (IFOV). Those problems, consequently, strongly limit the efficiency and the reliability of traditional satellite techniques. Recently, using data coming from AMSU (Advanced Microwave Sounding Unit), flying aboard NOAA (National Oceanic and Atmospheric Administration) satellites, a new methodology for soil wetness estimation has been proposed. The proposed index, called Soil Wetness Variation Index (SWVI), developed by a multi-temporal analysis of AMSU records, seems able to reduce the problems related to vegetation and/or roughness effects. Such an approach has been tested, with promising results, on the analysis of some flooding events which occurred in Europe in the past. [ABSTRACT FROM AUTHOR]

An inter-comparison exercise was performed between two laboratories on mineralized moss samples. Ten samples, together with three certified reference materials (CRM 61, CRM 62 and CRM 482) and five blanks were mineralized independently in the two laboratories and then analysed by both with different techniques (AAS, ICP-MS, and INAA). The elements analyzed were: Cd, Cr, Cu, Fe, Ni, and Pb. Accuracy tests showed that, for AAS, the relative standard deviations for five repetitions of the same sample were between 0.2 I for Cd and 2.9 % for Cr and that the concentration values found for reference materials were within one standard deviation from the certified values, with the exception of Cr and Cd for CRM 482. The statistical analysis was performed first with a simple linear regression and a Student t-test taking into account the possible influence of the mineralization procedure and ofthe analytical technique, in order to evaluate their reliability. The results showed that more than 78 % of the regressions had a correlation coefficient higher than 0.750, and that 83 % of the slopes were not different from ogre with a level of significance of 0.01. Afterwards, the precision of the measurements were evaluated using maximum likelihood; the normalized errors showed that 1CP-MS had a better performance on most of the elements analysed (with the exception of Fe) aril that both the mineralization procedures gave satisfactory results. The two laboratories were then found to produce reliable results. [ABSTRACT FROM AUTHOR]

An inter-comparison exercise was performed between two laboratories on mineralised moss samples. Ten samples, together with three certified reference materials (CRM 61, CRM 62 and CRM 482) and five blanks were mineralised independently in the two laboratories and then analysed by both with different techniques (AAS, ICP-MS, and INAA). The elements analysed were: Cd, Cr, Cu, Fe, Ni, and Pb. Accuracy tests showed that, for AAS, the relative standard deviations for five repetitions of the same sample were between 0.2% for Cd and 2.9 % for Cr and that the concentration values found reference materials were withn one standard deviation from the certified values, with the exception of Cr and Cd for CRM 482. The statistical analysis was performed first with a simple linear regression and a Student t-test taking into account the possible influence of the mineralisation procedure and of the analytical technique, in order to evaluate their reliability. The results showed that more than 78% of the regressions had a correlation coefficient higher than 0.750, and that 83% of the slopes were not different from one with a level of significance of 0.01. Afterwards, the precision of the measurements were evaluated using maximum likelihood; the normalised errors showed that ICP-MS had a better performance on most of the elements analysed (with the exception of Fe) and that both the mineralisation procedures gave satisfactory results. The two laboratories were then found to produce reliable results.