A 12-year radar-based climatology of daily and sub-daily extreme precipitation over the Swiss Alps
1MeteoSwiss, Switzerland; 2Oeschger Centre for Climate Change Research, Institute of Geography, University of Bern, Switzerland
The characterization of the alpine extreme precipitation is the basis to study the projected changes in frequency and intensity of heavy rainfall. We studied some climatological features of extreme daily and sub-daily precipitation in the Swiss Alps and surrounding regions, based on 12 years of data from rain gauges and CombiPrecip, a rainfall field with high spatial resolution (1 km2) produced by locally adjusting the radar precipitation map to the values measured by rain gauges.
We quantify the agreement between rain gauges and CombiPrecip concerning both the timing and the magnitude of the extreme events by cross-validation; overall, it increases with diminishing the severity of the extremes and increasing accumulation time.
The maps of our climatology prove that both daily and sub-daily extremes along the first alpine slopes exhibit very different climatological features with respect to the crest of the Alps and flat terrain.
We will also present the preliminary results of the radar-based extreme value analysis which we are developing with the same data set, in order to derive the return periods of heavy rainfall with relative confidence intervals for any ungauged location in the Swiss Alps.
Recent snowfall and skiing on the Slovenian Alps
1University of Camerino, Italy; 2Slovenian Environment Agency · Meteorological Office.
The Mediterranean mountain domains are identified as excellent indicators of climate change that has now been ascertained. In particular, the reliefs that make up the Slovenian Alps s.l., due to their geographical position - next to the Adriatic Sea and bordered by the vast continental plains of central - eastern Europe, constitute an climatological crossroads where different air masses continue to face each other, bringing abundant rainfall. Thanks to the consistency of homogeneous and continuous historical nivometric series, a statistical analysis was attempted of the nivometry of some mountain areas, located between 850 m. of elevation of Ratece and 2514 m. of Kredarica, to observe any significant variations in the snow signal and associated possibilities offered by winter tourism, a fundamental economic resource for the sustainable development of areas otherwise destined for a heavy depopulation. The snow data for eight measurement stations located in the Julian Alps, Kamnik and in the Carniola plateau have therefore been analyzed for seasons since the autumn of 1993 and until the winter of 2019. For the Ratece station - located near Kraniska Gora, a world-famous ski resort - the period extends from the winter of 1950-51 to the present. In this sense, the monthly and seasonal averages of fresh snow, the persistence of snow on the ground and the number of snowy days (with daily amount> 1 cm) and the relative trends were calculated. For the station of Ratece, the average temperatures and the number of naturally skiable days was also calculated. Evidently, as happens also in the neighboring Tridentine Alps, the signal of the fresh snow shows a recent tendency to a slight and increase, in relation to many particularly snowy seasons occurred in the last decade but, probably due to the notable increase of spring temperatures, the snowpack tends to remain on the ground for less time. Consequently, even the number of skiable days tends quickly to decrease, remaining on average well below the limit of 100 seasonal days - a fundamental condition for the economic subsistence of a ski area: It is therefore necessary, at least to these elevation, to resort to the production of technical snow to achieve a significant duration of the skiable period.
ANALYSIS OF TEMPORAL AND SPATIAL VARIATIONS OF SOME NIVOLOGIC PARAMETERS IN THE FRIULIAN MOUNTAIN
University of Camerino, Italy
The Friulian Alps show several particular meteorological and climatic features, deriving also from geographical position between the northern Adriatic basin to the south, the main Alpine watershed to the north (Tauern Alps) and the Carpathian chain to the east. Furthermore, there are numerous topoclimatic situations in relation to the geographical layout of the valleys that divide the main reliefs. All this makes the Friulian physical territory among the wettest in the entire Alpine region, with very abundant snowfall in relation to the altitude.
Thanks to the availability of continuous and fairly homogeneous historical series in the different regional mountain domains, a nivological characterization was attempted on the regional scale, with particular reference to the trend of the density of the fresh snow, of the number of days with thickness of snow - Hs> 30 cm - and the consequent average elevation of the boundary of 100 skiable days (LAN). The ten snow gauges object of the study are situated at elevation between 603 m. of Claut (Carnic Prealps) and 1843 m. of Rifugio Gilberti (Julian Alps) and the analysed timespan goes from the winter season 1990-91 to the 2016-17.
From this analysis, surprising data are derived. First of all, we note that the density (Kg / mc), which cannot be correlated with the altitude, tends to decrease in all the measurement stations, and this would seem to be in contrast with the strong thermal increase that is occurring also on the Friulian mountain. Therefore, it ‘s very probable that in the last few years the thermal characteristics have changed and maybe the main origin of the air masses bringing snow in the studied area.Below, we note for all the stations, an increase in the number of days with Hs> 30cm and, consequently, the average elevation of the limit of 100 days with natural skiability tends to decrease by about 6 m. per season, also it cannot be correlated with the aforementioned positive variation in temperatures and in disagreement with the corresponding signals calculated for the northern sides of the Alps.
The thermo - nivometric anomalies of spring 2019 on the Italian Eastern Alps
1University of Camerino, Italy; 2Autonomous Province of Trento - Civil Protection Department; 3University of Trento - Department of Civil, Environmental and Mechanical Engineering
After a decidedly mild and dry winter, spring 2019 showed, on the northernmost sector of the Mediterranean basin, strong snow and thermometric anomalies - the latter mainly positive in March and frequently negative in April and especially in May. For a poor snowfall winter - excluding the main watershed line, affected by significant stau phenomena from the north - starting from the middle of March and until the middle of April, a series of Atlantic frontal system has affected the southern eastern alpine sectors, bringing snowfalls in line with climate averages and corresponding to the bimodal nivometric regime. Following an atypical, intense and delayed Final warming maior – occurred between 24 and 25 April - and the strong definitive weakening of the tropospheric polar vortex, it has migrated towards the central - northern Europe. Associated events of marine or intermediate polar air masses towards the Mediterranean basin, have talking repeated low pressure on the northern Italy (conditions of persistent NAO-). Several phases of unstable or bad weather have occurred, with heavy precipitations and temperatures that have averaged below the average of the period. In particular, the fronts of 22-24 April, 27-29 April, 4-6 May, 11-12 May and 17-19 May were characterized by abundant snowfall, with limit of the phenomenology between the 600 and the 1200 meters – and from sudden fluctuations of the temperatures, that have shown strongly negative anomalies since on the 1000 m.
To quantify these events, thermo – nivometric data sets of approximately 35 automatic meteorological stations (AWS) were analysed, located in the Autonomous Province of Trento and in the Veneto region at altitudes between 1700 and 3250 m. approximately. At the date of 20 May, the snow cover was present throughout the analysed territory, with accumulations of fresh snow over a metre at 2500 m. and thicknesses reached the 380 cm In the first half of May, in all mountain territory, the temperatures have remained 3 - 4°C below the climatic averages and, above 3000 m, the maximum values never exceeded the 0°C, while the minimum values were frequently below -10°C.These anomalies would make it possible to state, at least for the elevation studied, that May 2019 would be the snowiest and coldest of the new millennium.
NATIONAL MONITORING AND MAPPING OF SNOWFALLS AND SNOW ON THE GROUND IN ITALY.
1METEOMONT CARABINIERI, Rome, Italy; 2MobyGIS srl, Trento, Italy; 3Civil Protection Department, Rome, Italy; 4METEOMONT CARABINIERI, Bologna, Italy
The present work reports the results obtained from a collaboration between METEOMONT CARABINIERI (CNM), the Civil Protection Department (DPC) and Mysnowmaps® for the implementation of a snow monitoring and mapping system, In terms of accuracy and usability of the service the results are promising, making it possible to generate the most extensive and homogeneous network and snow mapping of Italy, designed to be in support of the community, civil protection services, meteorological and hydrogeological risk management and warning, meteorological forecasting and climatological analysis. The CNM, a permanent member of the EAWS (European Avalanche Warning Services), carries out snow and avalanche monitoring and avalanche danger forecasting (ww.meteomont.gov.it). In support of the national civil protection system, in 2009 the CNM designed and implemented an itinerant snowfall monitoring system, called "Nevemont", producing data and information in real time. Mysnowmaps® (www.mysnowmaps.com) is a Web + App platform dedicated to winter off-piste skiers and hikers. Through a numerical modeling that triangulates in-situ data, satellite images and weather forecasts, Mysnowmaps® calculates snow depth in real time at high resolution, taking into account the altitude and the slope aspect. Recently, the data produced by "Nevemont" network, together with those produced by the fixed survey network located at high altitudes, have been put to system for feeding Mysnowmaps®. The calculation algorithm is based on a physically based modeling approach that takes high-resolution weather forecasts, in-situ snow measurements and satellite data as input. The system updates the snow height estimates on a daily basis, translating the meteorological trend occurring in a mass and energy balance in the snowpack. In this way it is possible to calculate the physical accumulation, compaction and fusion processes responsible for the snow evolution. The results are provided in the form of georeferenced maps of the various snow data (snow height, fresh snow, SWE).
A community-based analysis on snow precipitation trends in in the Alpine region Trentino Alto Adige
1Associazione Meteo Trentino Alto Adige, Trento, Italy.; 2Institute for Alpine Environment, Eurac research, Bolzano, Italy.; 3EUMETSAT, Darmstadt, Germany.; 4Oeschger Centre for Climate Change Research, University of Bern, Bern, CH.; 5Institute of Geography, University of Bern, Bern, CH.; 6Garda-meteo, Riva del Garda, Italy.; 7www.gardolo.it; 8www.meteoballino.it; 9www.meteomollaro.it; 10Department of Civil, Environmental and Mechanical Engineering, University of Trento, Italy.; 11www.meteolavis.it; 12Associazione Meteonetwork; 13www.meteogardolo.it; 14Fondazione Museo Civico di Rovereto
Snow is an important resource for the Alpine environment and for the economy of its valleys and it presence has a relevant impact on citizens life. In the southern side of the Alps and at mid and lower levels snow depends often on a fine balance between the availability of precipitations and low temperatures. To have a detailed picture of the changes in the winter snow accumulation a capillary network of observations is necessary, with manned stations integrating more sparse automated measurement. While at mid and high elevations are present extensive institutional networks, at the lowest elevation, where reside most of the population, time series are much more fragmentary. However, at the lowest elevations is where the reduction in the chances of colder conditions has most affected snow presence in the recent decades. Therefore, there is the need of an improved ground snow monitoring.
In Trentino-South Tyrol the members of an association of private citizen (Meteotrentinoaltoadige) has maintained a series of snow observations which spans the last 40 years, providing an interesting insight on the distribution and decadal changes in the winter snowfall at mid and low-elevation. We present here the first scientific exploitation of this record and explore its potential for the study of snow cover in complex terrain. We discuss uncertainties due different approaches in manually measuring snow and we highlight the observed trends. Despite a general decreasing trend, we notice strong local differences, related to orographic factors.
Climate change and snow cover decrease in the Alps: adaptation require appropriate numerical modeling and quantification
University of Trento, Italy
Climate change is having a significant impact on snow cover in the European Alps (, ): many studies show a general decrease in snow depth and snow cover duration, mainly due to warmer winter temperatures, and only above 2000 m a.s.l. due to precipitation reduction. Further temperature and snowfall changes will have high impacts mainly at low altitudes basins and southern valleys.
Since by 2099 is estimated that the Alps will lose the 70% of their snow cover area, adaptation is the key word. In turn, adaptation needs a correct modeling and quantification of two main elements: snow quantity and snow melting dynamics.
In this work, starting from the models in GEOframe New-Age (, ) and GEOtop (), we review some of the available numerical tools for snow quantification (, ) and compare their approaches in describing the surface processes, snow water equivalent (SWE) and snow ablation/melting. Finally, we try to assess, how they can be enhanced to improve the support they give to water resources management.
 Endrizzi, S., Gruber, S., Dall’Amico, M., & Rigon, R. (2014). GEOtop 2.0: Simulating the combined energy and water balance at and below the land surface accounting for soil freezing, snow cover and terrain effects. Geoscientific Model Development. https://doi.org/10.5194/gmd-7-2831-2014
 Formetta, G., Mantilla, R., Franceschi, S., Antonello, A., & Rigon, R. (2011). The JGrass-NewAge system for forecasting and managing the hydrological budgets at the basin scale: Models of flow generation and propagation/routing. Geoscientific Model Development. https://doi.org/10.5194/gmd-4-943-2011
 Formetta, G., Kampf, S. K., David, O., & Rigon, R. (2014). Snow water equivalent modeling components in NewAge-JGrass. Geoscientific Model Development, 7(3), 725–736. https://doi.org/10.5194/gmd-7-725-2014
 Lehning, M., Völksch Ingo, I., Gustafsson, D., Nguyen, T. A., Stähli, M., & Zappa, M. (2006). ALPINE3D: A detailed model of mountain surface processes and its application to snow hydrology. Hydrological Processes. https://doi.org/10.1002/hyp.6204
 Marty, C. (2017). Climate Change and Snow Cover in the European Alps. The Impacts of Skiing and Related Winter Recreational Activities on Mountain Environments, (January 2013), 30–44. https://doi.org/10.2174/9781608054886113010005
 Marty, C., Schlögl, S., Bavay, M., & Lehning, M. (2017). How much can we save? Impact of different emission scenarios on future snow cover in the Alps. Cryosphere, 11(1), 517–529. https://doi.org/10.5194/tc-11-517-2017
 Vionnet, V., Brun, E., Morin, S., Boone, A., Faroux, S., Le Moigne, P., Willemet, J. M. (2012). The detailed snowpack scheme Crocus and its implementation in SURFEX v7.2. Geoscientific Model Development. https://doi.org/10.5194/gmd-5-773-2012
Spatially heterogeneous impacts of global warming on heavy wet snowfall
Central Research Institute of Electric Power Industry, Japan
Wet snow is one of the main causes of atmospheric icing, which cause severe damages on towers and power lines that leads to a huge electricity breakdown or blackout. The systems are often located in high mountain regions. The impacts of global warming/climate change on heavy wet snowfall events during winter period in Japan and their dependency on weather patterns (WPs) were examined using the self-organizing maps (SOM). To investigate the differences in climate change impacts on daily wet snowfall among the WPs, a SOM was applied to surface atmospheric circulation data from the Database for Policy Decision Making for Future Climate Change (d4PDF) to determine the dominant heavy wet-snowfall WPs. The obtained SOM shows that different WPs are associated with heavy wet snowfalls in Japan.
Projected future changes in the occurrence of heavy wet-snowfall displayed a non-uniform spatial distribution. To understand the spatial heterogeneous wet-snowfall changes, the impact of climate forcing on the heavy wet-snowfall WPs was evaluated. Results of the SOM analysis suggest that the spatially heterogeneous future changes in extreme wet-snowfalls could be attributed to differences of the response to the climate changes among the WPs. This can be attributed to the WP by WP difference in future changes of the freezing point line which is important to cause wet snowfalls. Orographic effect is also discussed.
Precipitation downscaling in complex topography with ICAR evaluated with a weather-pattern based approach
Universität Innsbruck, Austria
The coarse grid spacing of global circulation models necessitates the application of climate downscaling to investigate the local impact of a changing global climate. Difficulties arise for data sparse regions in complex topography which are computationally demanding for dynamic downscaling and often not suitable for statistical downscaling due to the lack of high quality observational data. The Intermediate Complexity Atmospheric Research Model (ICAR) is a physics-based model that can be applied without relying on measurements for training and is computationally more efficient than dynamic downscaling models. This contribution presents the first in-depth evaluation of multi-year precipitation time series generated with ICAR on a 4 x 4 km² grid for the South Island of New Zealand for the eleven-year period from 2007 to 2017. It focuses on complex topography and evaluates ICAR at eleven weather stations situated in the Southern Alps. ICAR is diagnosed with standard skill scores and the effect of model top elevation, topography, season, atmospheric background state and synoptic weather patterns on these scores are investigated. The results show a strong dependence of ICAR skill on the choice of the model top elevation. ICAR was forced with ERA-Interim and ERA-5 reanalyses and was found to provide added value over both forcing data sets. Forced with ERA-Interim it performs similarly during all seasons, while flow of higher linearity and atmospheric stability were found to increase skill scores. ICAR scores are highest during weather patterns associated with flow perpendicular to the Southern Alps and lowest for flow parallel to the alpine range. While measured precipitation is underestimated by ICAR, these results may be improved upon by further observational tuning or bias correction techniques. Based on these findings ICAR shows the potential to generate downscaled fields for long term impact studies in data sparse regions with complex topography.
Mountains and the persistence of mean temperatures on a monthly scale
1Freie Univ. Berlin, Univ. Iceland and the Icelandic Meteorological Office; 2University of Iceland and the Icelandic Meteorological Office Iceland
Exploration of data from Iceland and Continental Europe reveal several connections between topography and the persistence of mean temperatures on the scale of month(s). These connections are associated with snow cover, thermally driven winds and sheltering and they will be illustrated in the poster.
Orographic impact on seasonal temperature persistence in Croatia
1Croatian Meteorological and Hydrological Service; 2Freie Univ. Berlin, Univ Iceland and Icelandic Meteorol. Office; 3University of Iceland and the Icelandic Meteorol. Office
Long time series of temperatures in Croatia are explored. There is substantial persistence in mean monthly temperatures and this persistence depends on season and is different in coastal and inland areas. On a smaller scale, there is a topographic signal along the Adriatic coast as well as further inland. The topographic signal is most likely associated with snow cover and with blocking or channeling of continental air.
Modelled wind gust climatology over the Adriatic region
Croatian Meteorological and Hydrological Service
The global model reanalysis, forecast or climate data needs to be downscaled to provide information for regional interpretation. This is especially true in complex terrain of Croatia, where weather conditions are governed by the effects of mountains and the Adriatic Sea and the atmosphere. One of the climatological particularities of the region is related to bora winds, severe downslope windstorms. Bora winds are especially frequent in winter and may reach hurricane 5 scale gusts, therefore being a major threat to population safety and coastal infrastructure.
Dynamical downscaling of global reanalysis data was performed with the use of ALADIN model at the final grid spacing of 2 km during a 10-year period. Moment-based and spectral verification of wind speed, performed on a number of surface stations in different climate regions of Croatia, suggested that downscaling was successful. The highest modelled wind gust 'reached ~ 68 m/s near the lee of the southern Velebit Mountain, which is in an excellent agreement with the intensity and location of the highest observed maximal gusts. Results suggest ALADIN wind and wind gust climatology is appropriate for using in studies of air-sea interaction and hydrological cycle over the Adriatic where the observed data is scarce, as well as for a range of other purposes such as infrastructure planning and offshore wind resource potential estimates.
Effect of climate change on the natural broadleaf forests of the Eastern Galician Mountains
University of Santiago de Compostela, Spain
In the current climate change state, the climatic progression in the study area is favoring the forest expansion, due to the progressive increase of temperatures and, in general, to the maintenance of precipitation, although with nuances as important as they are, the significant decrease in precipitation in the form of snow and a shorter duration of the cold season. The goal of our research is to study the evolution and historical background of the natural broadleaf forests to establish measures for their conservation and recovery. These forests were intensively exploited since ancestral times. Now, socioeconomic globalization has promoted intense changes in rural areas. The decrease in open spaces due to rural depopulation has led to a natural expansion of forests and has affected the environment, biodiversity and landscape. The landscape homogenization means reduction of open habitats (crops, grasslands, and scrublands), difficulty in the maintenance of agro-pastoral activities, and increasing risk of wildfires due to decrease in fragmentation. In addition, from the biological perspective, an increase in forest species and core habitat specialists is expected to the detriment of open-habitat and ecotone species.
In this context, the sustainability of forest management depends mainly on the maintenance of traditional activities: extensive agro-pastoral exploitation and rational management of forests. Extensive grazing, allowing a suitable number of livestock and avoiding their concentration in small areas, prevents soil erosion and vegetation impoverishment, increases mosaic diversity, and maintains open-habitat patches. Selective logging appears to be an environmentally integrated and viable economic activity that reduces wildfires by promoting landscape fragmentation. To guarantee the sustainability of these activities, measures such as clear cutting and prescribed burning to create open habitats, improvement of forest access, increment of public awareness about mountainous areas, and agro-environmental measures need to be adopted at regional, national and European levels. The environmental, cultural and economic integration of agro-pastoral and forestry activities seems fundamental to ensure the conservation of this landscape mosaic, which is essential to the biodiversity.
Algae-pollen monitoring in alpine-taiga Altai Biosphere Reserve (Altai Republic, Russia) as a key area for climate and environment change observation
1Institute for Water and Environmental Problems SB RAS, Russian Federation; 2Altai State University, Altai Krai, Russian Federation
Primary biological aerosols (PBAP) are a group of particles of biological origin (algae, archaea, bacteria, fungal spores, plant pollen) playing an important role in the interaction between the biosphere and atmosphere and influencing the climate (Despres et al., 2012, etc.). PBAP are condensation nuclei contributed to the cloudiness development, redistribution of radiation fluxes and an increase in precipitation that can significantly affect the hydrological and climatic cycles on a global and regional scale (Hoose et al., 2012; etc.).
The results of studies of pollen and algae in precipitation deposited on the territory of the Altai Biosphere Reserve from July to October 2017 are presented. The reserve is located in the Altai Mountains, its area is 87120.6 km2 (including the reserved part of the Lake Teletskoye water area – 114.1 km2) and the height difference makes up 434-3500 m above sea level. In the analyzed samples, 28 taxa of pollen grains and algae were interpreted. Pollen grains belonged to woody (Pinus sylvestris, Betula sect. Albae sp., Acacia dealbata, Populus sp.), herbaceous (Carax sp., Thalictrum sp., families Asteraceae, Chenopodiaceae, Fabceae, Poaceae, Ranunculaceae, Brassicaceae) and the brush (family Ericaceae) forms. All of them are anemophilous plants, the pollen of which can be transported for long distances. Algae from divisions Сyanobacteria, Chrysophyta, Bacillariophyta, Euglenophyta, Cryptophyta, Chlorophyta and Xanthophyta were mainly represented by widespread taxa, many of which can be found in small reservoirs of the Lake Teletskoye catchment.
Using of the HYSPLIT model, major regions-suppliers of pollen and algae to the Altai Biosphere Reserve for the specified period were determined. In July, the air masses were of western and south-western direction at the regional level and north-western – at the local one, in August – north-western and western; in September – south-western at the regional level, in October – southern and south-eastern direction both at local and regional levels.
Climate changes and extreme events in Altai Mountains
1Institute for Water and Environmental Problems, Siberian Branch of the Russian Academy of Sciences, Russian Federation; 2CITEUC, University of Coimbra, Almas de Freire, Sta. Clara, Coimbra, 3040-004, Portugal; 3Khovd State University, Mongolia
The effects of climate change are observed in different areas of the Earth, but it was found that they are more pronounced in mountainous regions. Altai is a large mountain region with greatly variable climate, located in the transition zone between Siberian taiga forests and Central Asian deserts. Using climatological data (1979-2017) from Mongolia’s National Agency for Meteorology, Hydrology and Environment Monitoring, RosHydromet and reanalysis ERA-Interim climate changes in this mountain region were calculated. Based on the step change analysis, we divided the studied period (1979-2017) into two time subintervals at the step change point and compared them between each other. Step change points are found in precipitations in 2003 and in temperature in 1997. Precipitation in the second period (2003-2017) declined relative to the first period (1979-2002) from 421 mm to 362 mm, while the main contribution to the decrease was determined by summer precipitations (from 196 to 145 mm). The change in summer temperature also significantly influenced the changes in the annual temperature. The annual temperature was negative (-0.27°С) until 1997, and became positive after (+0.32°С). With this, the summer temperature increased by more than 1°С degree (from + 15°С to 16.1°С degrees). Climate changes in this mountain region during the two past decades led to intensification of extreme events, eg, dzud in 2009/2010 (Mongolia, Khovd aimag).
Reactivation of the ice of the cave "Bus del Giaz" (Paganella summit, Trento, Italy)
1MUSE - Science Museum of Trento, Italy; 2Department of Environmental Engineering, University of Trento, Italy
Inside “Bus del Giaz” cave, located just below Paganella summit (Trento, Italy) at the altitude of 1950 meters, ice was present until the early 2000s and was preserved throughout the summer season.
With the inauguration of the cable car that went up from Fai della Paganella in 1930, locals began to dig and carry ice down to the hotels to store food and medicinals.
In 2004, during the enlargement of a ski slope with the consequent movement of material by mechanical means, the vault of the cave was broken. Since then, because of the micro-climatic changes inside the karst cavity, all the ice melted.
In 2016, the same company that 10 years earlier, with the construction of the new ski slope, destroyed the cave, wanted to investigate the possibility of restoring the site.
It was hypothesized to use the snow (both natural and artificial) of the slope and accumulate it inside the cave to restore the ice. In fact the snow can be easily thrown into the cave by the openings of the vault formed in 2004, which have now been covered by grids.
In summer 2016 and in the following winter the temperature of the cave was monitored. At the end of the 2016-17 ski season the first snow was pushed inside.
Thanks to the melting-freezing cycle it is now possible to measure a density of transformed snow very close to the ice one.
Therefore it seems possible to restore the original conditions using the snow on the ski slopes.
The site could become an important point of environmental interest, since it’s an excellent indicator of the effects of climatic variations in all those layers of the subsoil that would otherwise be difficult to monitor and a touristic attraction as well, making the visitor aware of issues related to the mountain climate, telling a story that connects local traditions with the surrounding environment.
The San Rocco Meteorological Observatory in Rovereto (TN): over 130 years of data since 1882
1Fondazione Museo Civico di Rovereto, Italy; 2Associazione di Promozione Sociale "Meteo Trentino Alto Adige"
The Rovereto Civic Museum Foundation has always been concerned with safeguarding and enhancing data from the historic Meteorological Observatory of Rovereto (TN), established in 1882 and located in the former Convent of San Rocco's franciscan friars. This still-functioning installation consists of a series of tools used to monitor an extremely representative climate of the pre-Alpine valley floor in the southern slope of the Alps. The oldest part of the instrumentation belonging to the observatory has always been included in a meteorological shelter that protrudes from the second floor of the former convent of San Rocco, now a school. Here, every day - at 8:00 am, at 2:00 pm and at 7:00 pm - the data coming from a meteorological station are saved, integrated with the observation of the state of the sky, accompanied by eventual annotations relating to the most significant events and entered in digital registers, which since 2014 have officially superseded the paper ones, drawn up since 1882. The analysis of the data coming from this observatory, a long series of more than 130 years, allows us to know with extreme precision the climate of this geographical area and above all to grasp the effects, on a local scale, of the current climate changes.
Mountain snow simulations and projections: from global to local scales
National Research Council of Italy, Institute of Atmospheric Sciences and Climate, Torino, Italy
The representation of the mountain cryosphere in climate models is critical owing to the scale mismatch between the spatial resolution reproduced by climate models, typically ranging between 100 and 10 km, and the scales at which snow-related processes occur, which is finer than 1 km.
We provide an overview of the state-of-the-art global and regional climate model simulations from the CMIP5 and EURO-CORDEX experiments by comparing the model representations of the snow water equivalent (SWE) climatology over the Greater Alpine Region (4–19°E, 43–49°N) in the last decades (1980-2005) and in future projections (mid-century, 2040-2065). We assess the changes in the drivers of snow processes (air temperature, total precipitation) and in SWE outputs. Results show that, compared to global coarse-scale runs, in the finer-resolution regional model runs colder temperatures and a slightly higher amount of snow precipitation lead to a significantly thicker snow depth. The spatial resolution is found to play a crucial role for the snowpack simulations, and we conclude that high-resolution modelling is required to improve the representation of current and future snowpack dynamics.
One possible strategy to improve current snow water equivalent simulations in mountain areas is to downscale the meteorological variables produced by regional climate models by employing detailed snow models which can be run at spatial resolutions of the order of hundreds of meters. However, snow models span a large range of complexity, from very detailed multi-layer snow models to simpler empirical models, making it difficult to identify the minimum degree of complexity required to achieve accurate snow water equivalent simulations. A preliminary study assessing the sensitivity of snow models with different degrees of complexity to the accuracy of their meteorological inputs, through comparison with observations at the experimental site of Torgnon (northwester Alps), will be presented.