Stations In Austria Research Articles

Atlantic Ocean Variability and European Alps Winter Precipitation

Winter precipitation (snowpack) in the European Alps provides a critical source of freshwater to major river basins such as the Danube, Rhine, and Po. Previous research identified Atlantic Ocean variability and hydrologic responses in the European Alps. The research presented here evaluates Atlantic Sea Surface Temperatures (SSTs) and European Alps winter precipitation variability using Singular Value Decomposition. Regions in the north and mid-Atlantic from the SSTs were identified as being tele-connected with winter precipitation in the European Alps. Indices were generated for these Atlantic SST regions to use in prediction of precipitation. Regression and non-parametric models were developed using the indices as predictors and winter precipitation as the predictand for twenty-one alpine precipitation stations in Austria, Germany, and Italy. The proposed framework identified three regions in the European Alps in which model skill ranged from excellent (West Region–Po River Basin), to good (East Region) to poor (Central Region). A novel approach for forecasting future winter precipitation utilizing future projections of Atlantic SSTs predicts increased winter precipitation until ~2040, followed by decreased winter precipitation until ~2070, and then followed by increasing winter precipitation until ~2100.

Mapping snow cover from daily Collection 6 MODIS products over Austria

Moderate Resolution Imaging Spectroradiometer (MODIS) snow cover maps have been successfully applied in regional snow cover mapping and hydrological modelling in many regions. The new MODIS products (i.e. Collection 6) provide information about the Normalized Difference Snow Index (NDSI) instead of simple binary information about snow cover of the former products. The objective of this study is to investigate the sensitivity and accuracy of different NDSI thresholds used for snow cover mapping and to compare the results with former snow cover classification based on a fixed NDSI threshold (NDSI = 0.4). The accuracy is tested for both Aqua (MYD10A1) and Terra (MOD10A1) daily snow cover products by using daily snow depth observations at 665 climate stations in Austria in the period 2002–2014. The results show the overall classification accuracy over 665 climate stations to be larger than 97% (97.4% for Terra and 97.6% for Aqua) in Austria. The best NDSI thresholds fitted to individual stations can differ from a fixed threshold (NDSI = 0.4) and are sensitive to the snow depth threshold indicating snow cover at the ground. The NDSI thresholds vary seasonally, decrease with increasing elevation and are lower in forested than open land cover settings. We found that the NDSI thresholds fitted to different elevation and land cover classes improve regional snow cover mapping by 3–10% in forested regions above 900 m a.s.l. in January to March.

A New Horizontal Length Scale for a Three-Dimensional Turbulence Parameterization in Mesoscale Atmospheric Modeling over Highly Complex Terrain

AbstractThe correct simulation of the atmospheric boundary layer (ABL) in highly complex terrain is a challenge for mesoscale numerical weather prediction models. An improvement in model performance is possible if horizontal contributions to turbulence kinetic energy (TKE) production, such as horizontal shear production, are implemented in the model’s turbulence parameterization. However, 3D turbulence parameterizations often only have a constant horizontal length scale that depends on the horizontal grid spacing. This is unphysical for mesoscale applications, because such parameterizations were initially developed for much smaller model grid spacings (e.g., for large-eddy simulations). In this study, we develop a new physically based horizontal length scale for the high-resolution mesoscale model COSMO. We analyze days dominated by thermally driven circulations (valley wind days) in the Inn Valley, Austria. Results show that the new horizontal length scale improves TKE simulations in the valley, when horizontal shear processes contribute to the overall TKE budget. Vertical profiles of TKE and transects across the valley indicate that the model simulates the ABL in a more realistic way than standard turbulence schemes, because the new scheme is able to account for terrain inhomogeneities. A model validation with 88 stations in Austria for four case study days indicates no change in the mean surface fields of temperature, relative humidity, and wind speed by the new turbulence parameterization.

Desert Dust Contribution to PM10 Loads in Styria (Southern Austria) and Impact on Exceedance of Limit Values from 2013–2018

From a legislators point of view, the contribution of natural sources to PM10 loads is relevant since their impact can be subtracted from the daily limit value of PM10 as regulated in a working staff paper by the European Commission (EC), supporting the European Air Quality Directive (2008/50/EC). This work investigates its applicability for two stations in Austria over a time period of six years (2013 to 2018), as the occurrence of long-range transport of desert dust is observed on a regular base. Different stations and different statistical parameters were evaluated to determine the regional background load and subsequently the net dust load (NDL). Results reveal an adapted approach of the methodology described by the EC, using the +/− 15-day mean average of the PM10 at the regional background station, together with threshold criteria to identify only desert dust affected days. The results of calculated NDLs were in good agreement with crustal loads determined on filter samples during two desert dust events in 2016. Thus, the application of the EC method for a region in Central Europe, which experiences a regular but less pronounced impact of desert dust than stations in the Mediterranean, is discussed.

Crustal geomagnetic field and secular variation by regional and global models for Austria

Abstract Using 12-year-long series of data (2001-2012) from geomagnetic observatories and repeat stations in Austria and its neighboring countries, a regional spatial-temporal (ST) model is developed based on the polynomial expansion consisting of latitude, longitude, and time of the geomagnetic field components and total magnetic field F. Additionally, we have used three different global models (CHAOS-5, POMME-9, and EMM2015), which are built on spherical harmonics up to a maximum degree Lmax and give the core field and crustal field separately. The normal field provided by the ST model and its “model bias”, which comprise the residuals of the differences between measured and predicted values, are calculated and the respective maps are shown. The residuals are considered an estimate of the local crustal field. In the case of global models, we have applied for each of these three methods to calculate the “model bias”: residuals of the differences between observed values and predicted values of the model, residuals of the differences between observed values and core field values of the model, and the average bias for the period 2001-2012. The normal field of the region of Austria provided by each global model is also calculated. Generally, the regional and global models yield relatively similar crustal fields for the Austrian region, especially when the first method is used. The normal fields calculated by them are in good agreement with each other. Each of the global models directly provides the crustal field, and they are compared with the aeromagnetic data provided by aeromagnetic surveys over the Austrian region. The ST model is in better agreement with aeromagnetic data. We have also analyzed the secular variation over the region, which is calculated from the rate of change of normal field given by the ST and global models.

Price transmission and local market power: empirical evidence from the Austrian gasoline market

ABSTRACTWe analyse the impact of local market power on price margins and different dimensions of price adjustment dynamics (speed and asymmetry of price transmission) using data for a large number of individual gasoline stations in Austria. Specific attention is paid to threshold effects in price adjustment. Our results clearly suggest that the speed of price transmission between the Brent crude oil index and retail diesel prices is higher in a more competitive environment. While evidence on the relationship between local market power and asymmetries in the speed of price adjustment is mixed, our findings regarding asymmetries in price thresholds are clear: in regions where competition from neighbouring rivals is weak and/or consumers’ price elasticity of demand is low (stations located on the highway), positive thresholds significantly exceed negative ones, which corresponds to the ‘rockets and feathers phenomenon’. As expected, we observe that prices are lower in more competitive local markets.

Historic nitrogen deposition determines future climate change effects on nitrogen retention in temperate forests

Nitrogen (N) cycle processes in terrestrial ecosystems are highly sensitive to temperature and soil moisture variations. Thus, future climate change may affect the degree to which N deposited from the atmosphere will be retained in forest ecosystems. We evaluated the effect of future changes in climate and N deposition on ecosystem N cycling using the model LandscapeDNDC forced with historical data from eight long-term forest ecosystem monitoring stations in Austria and downscaled future N deposition and climate scenarios. With every 1 °C of warming, annual N uptake in biomass increased by +0.03 to +0.54 kg N ha−1, total soil organic matter (SOM) increased annually by +0.003 to +0.08 kg N ha−1, and mean annual N leaching was between −0.09 and −2.03 kg N ha−1 lower. The magnitude of N deposition in the years from 1990 to 2010 was by far the most important determinant of the response of nitrogen cycling to future warming, including statistically significant relationships with humus N content and N leaching. We conclude that climate change will likely increase ecosystem N retention in temperate forest ecosystems, and even more so at forest sites with high past N deposition.

Time as a strategic variable: business hours in the gasoline market

ABSTRACTA popular argument in policy discussions on the liberalization of business hours proceeds on the assumption that business hours are strategic complements: if some firms open longer hours, competitors will be forced to extend their opening hours too. We provide first empirical evidence on the impact of competition and the form of strategic interaction in business hours between firms by using detailed information on business hours as well as the location of retail gasoline stations in Austria. Our findings reject the presumption of business hours being strategic complements. Firms tend to have longer opening hours in a more competitive environment.

The role of station density for predicting daily runoff by top-kriging interpolation in Austria

Abstract Direct interpolation of daily runoff observations to ungauged sites is an alternative to hydrological model regionalisation. Such estimation is particularly important in small headwater basins characterized by sparse hydrological and climate observations, but often large spatial variability. The main objective of this study is to evaluate predictive accuracy of top-kriging interpolation driven by different number of stations (i.e. station densities) in an input dataset. The idea is to interpolate daily runoff for different station densities in Austria and to evaluate the minimum number of stations needed for accurate runoff predictions. Top-kriging efficiency is tested for ten different random samples in ten different stations densities. The predictive accuracy is evaluated by ordinary cross-validation and full-sample crossvalidations. The methodology is tested by using 555 gauges with daily observations in the period 1987-1997. The results of the cross-validation indicate that, in Austria, top-kriging interpolation is superior to hydrological model regionalisation if station density exceeds approximately 2 stations per 1000 km2 (175 stations in Austria). The average median of Nash-Sutcliffe cross-validation efficiency is larger than 0.7 for densities above 2.4 stations/1000 km2. For such densities, the variability of runoff efficiency is very small over ten random samples. Lower runoff efficiency is found for low station densities (less than 1 station/1000 km2) and in some smaller headwater basins.

Ragweed (Ambrosia) pollen source inventory for Austria

This study improves the spatial coverage of top-down Ambrosia pollen source inventories for Europe by expanding the methodology to Austria, a country that is challenging in terms of topography and the distribution of ragweed plants. The inventory combines annual ragweed pollen counts from 19 pollen-monitoring stations in Austria (2004–2013), 657 geographical observations of Ambrosia plants, a Digital Elevation Model (DEM), local knowledge of ragweed ecology and CORINE land cover information from the source area. The highest mean annual ragweed pollen concentrations were generally recorded in the East of Austria where the highest densities of possible growth habitats for Ambrosia were situated. Approximately 99% of all observations of Ambrosia populations were below 745m. The European infection level varies from 0.1% at Freistadt in Northern Austria to 12.8% at Rosalia in Eastern Austria. More top-down Ambrosia pollen source inventories are required for other parts of Europe. Capsule abstractA method for constructing top-down pollen source inventories for invasive ragweed plants in Austria, a country that is challenging in terms of topography and ragweed distribution.

CITLIVOST RŮSTOVÝCH SIMULAČNÍCH MODELŮ NA VYPOČTENÉ HODNOTY GLOBÁLNÍHO SLUNEČNÍHO ZÁŘENÍ

The results of the previous studies have suggested that the estimated RG values are loaded with an error, which might compromise the precision of the subsequent crop model applications. Therefore a detailed analysis of the error propagation was made using two crop models i.e. CERES-Barley and CERES-Wheat. Database of meteorological data originating from 8 stations in Austria and Czech Republic was used in order to carry out the analysis. It has been found that even application of the method based on sunshine duration that yield the lowest bias in RG estimates significantly influences number of key crop model outputs. It has been also noted that in 5–6 seasons out of 100 cases the deviation greater than ±10 % is to be expected whilst the occurrence of ±25% could not be also ruled out. The precision of the yield estimates and other crop model outputs is lower then expected but still acceptable for most application with mean bias error in range of 2.0–4.1% when estimates based on the diurnal temperature range and cloud cover are used. In this case yield deviations over ±10% occurred in about 20% cases (depending on the crop) whilst the probability of significant yield departure (±25%) doubled of that found for the previous method. The methods based on the diurnal temperature range and daily precipitation sum showed an increase of the systematic bias of yield of winter wheat and considerably higher number of seasons with yield departures over ±25%. Utilisation of the methods based on the diurnal temperature range only for the purposes of seasonal yield forecasting or climate change impact assessment is questionable as the probability of significant yield departure is very high (as well as the systematic error). These findings should act as an incentive to the further research aimed at development of more precise and widely applicable methods of estimating daily RG based more on the underlying physical principles and/or remote sensing approach. Overall decrease of the existing uncertainties in the RG estimates would clearly result into increase of the reliability of subsequent applications that use RG as input variable.

Do Emotions Pay Off? Effects of Media Brand Emotions on Cognitive Relief, Identification and Prestige

While in early days of communication research emotions were rather treated as „noise‟, today there is a growing number of studies showing the important role of emotions influencing media selection, perception and interpretation. These developments run in parallel to branding theory, where emotional branding has emerged as a highly influential branding paradigm. The present study analyses the emotions recipients associate with different television stations, and it identifies their impact on audience-related functions of media brands as suggested by previous research, i.e., complexity and risk reduction, self-definition, and self-expression. An online study has been conducted for one media category, namely television stations in Austria (n = 495). As the results indicate, emotions affect cognitive relief and they support the perception of brands as means for self-definition and self-expression. Joy, trust, pride and boredom are the most influential emotional drivers for these functions. The findings not only suggest concrete implications for communication activities and media branding strategists, they also uncover „white spaces‟ on the communication research agenda, where emotions should get a deeper theoretical and methodological debate.

Spatial and temporal predictors of melanoma incidence in Austria: Results of en ecologic study.

Objectives: Melanoma incidence increased in Austria in the last decades. Solar UV radiation increased until recently because of the damage to the ozone layer. With the restoration of the ozone layer UV radiation is predicted to decline again. If the increase in melanoma incidence were mostly due to the change in natural UV radiation we might expect declining incidence rates in the future. Exposure data: We assessed trends in UV annual cumulative doses at 9 fixed monitoring stations in Austria since 1961. There was strong inter-annual variation that was deemed not relevant for melanoma incidence. Apart from that, we observed an increase in annual cumulative UV dose of 1.2 kJ/m² per year consistently across stations. The only predictor of differences found between stations was the height above sea level with a gradient of 13.1 kJ/m² per 100 meter. Health data and methods: We obtained population data and melanoma incidences per 5-year age groups and gender for all 120 districts of Austria. We performed Poisson regression for each gender-age group with the gender-age specific population size as offset and year and height above sea level as predictor variables. Results: Averaged across strata melanoma incidence increased by 2% annually and by 20% per 100 m increase of height above sea level of the district. This fits well with the change in cumulative UV dose for these predictors. Effects were consistently stronger in younger age groups. Discussion and conclusions: Not only cumulative dose but also day-by day variability of UV radiation increased by year and by height above sea level with the strongest variation seen in summer. Since melanoma risk might be affected most strongly by peak exposures, for future scenarios not only cumulative average exposure but also variability and peak exposures would be of interest.

The relevance of glacier melt in the water cycle of the Alps: the example of Austria

Abstract. This paper quantifies the contribution of glacier melt to river runoff from compilation and statistical interpretation of data from available studies based on observations or glacio- hydrological modelling for the region of Austria (Austrian Salzach and Inn river basin). A logarithmic fit between the glacier melt contribution and the relative glacierized area was found not only for the long-term mean glacier contributions but also for the glacier melt contribution during the extreme hot an dry summer of 2003. Interestingly, the mean contributions of glacier melt to river runoff do not exceed 15 % for both river catchments and are uncorrelated to glacierization for glacierization values >10 %. This finding, however, has to be seen in the light of the general precipitation increase with altitude for the study region which levels out the increase of absolute melt with glacierization thus resulting in the rather constant value of glacier melt contribution. In order to qualitatively proof this finding another approach has been applied by calculating the quotient qA03 of the mean monthly August runoff in 2003 and the long-term mean August runoff for 38 gauging stations in Austria. The extreme summer 2003 was worth to be analysed as from the meteorological and glaciological point of view an extraordinary situation was observed. During June and July nearly the entire snow-cover melted and during August mainly bare ice melt of glaciers contributed to runoff. The qA03 quotients were calculated between 0.32 for a non-glacierized and 2.0 for a highly glacierized catchment. Using the results of this study the mean and maximum possible glacier melt contribution of catchments can be estimated based on the relative glacierized area. It can also be shown that the found correlation of glacierized area and glacier melt contribution is applicable for the Drau basin where yet no results of modelled glacier melt contributions are available.

Air quality model for Austria: development and evaluation of ozone forecasts

An overview of the main findings of recent sensitivity studies and evaluations of ozone forecasts of the Air Quality model for Austria (AQA) is presented. Before the operational forecasts were started at the ZAMG, studies with different model input were conducted to find the appropriate model set-up. The performance of the chemical mechanisms CB-IV and SAPRC99 is shown for a hot period with numerous exceedances of ozone thresholds in August 2003. The operational model forecasts of ozone concentrations in 2006 and 2007 are evaluated with the observations of 121 air quality stations in Austria. In addition to the evaluation of the operational forecasts, sensitivity studies with different input parameters for the model were conducted. The results of the implementation of the emission model SMOKE for biogenic emissions are shown for a selected period in 2007 and reveal the importance of these emissions in comparison with the anthropogenic contribution.

Reconstruction of erythemal UV-doses for two stations in Austria: a comparison between alpine and urban regions

Abstract. The aim of this study is the reconstruction of past UV-doses for two stations in Austria, Hoher Sonnblick and Vienna, using a physical radiation transfer model. The method uses the modeled UV-dose under clear-sky conditions, cloud modification factors and a correction factor as input variables. To identify the influence of temporal resolution of input data and modification factors, an ensemble of four different modelling approaches was calculated, each with hourly or daily resolution. This is especially important because we found no other study describing the influence of the temporal resolution of input data on model performance. Following the results of the statistical analysis of the evaluation period the model with the highest temporal resolution (HMC) was chosen for the reconstruction of UV-doses. A good agreement between modelled and measured values of erythemally effective UV-doses was found at both stations. In relation to the reference period 1976–1985 an increase in the erythemal UV-dose in Vienna of 11% is visible in the period 1986–1995 and an increase of 17% in the period 1996–2005 can be seen. At Hoher Sonnblick the corresponding increase is 2% and 9%. For the different seasons the strongest increase in erythemal UV-dose has been found for winter and spring season at both stations. Further the influences of total ozone and cloudiness on changes in erythemal UV-doses were analyzed. This analysis showed for both stations, that changes in total ozone had a larger influence on erythemal UV-doses than changes in cloudiness.

Optimal location of wood gasification plants for methanol production with heat recovery

Second generation biofuels from wood gasification are thought to become competitive in the face of effective climate and energy security policies. Cost competitiveness crucially depends on the optimization of the entire supply chain—field-wheel involving optimal location, scaling and logistics. In this study, a linear mixed integer programming model has been developed to determine the optimal geographic locations and sizes of methanol plants and gas stations in Austria. Optimal locations and sizes are found by the minimization of costs with respect to biomass and methanol production and transport, investments for the production plants and the gas stations. Hence, the model covers competition in all levels of a biofuel production chain including supply of biomass, biofuel and heat, and demand for bio- and fossil fuels. The results show that Austria could be self-sufficient in the production of methanol for biofuels like M5, M10 or M20, using up to 8% of the arable land share. The plants are optimally located close to the potential supply of biomass (i.e. poplar) in Eastern Austria, and produce methanol around 0.4 € l−1. Moreover, heat production could lower the methanol cost by 12%. Copyright © 2008 John Wiley & Sons, Ltd.

Austrian pumped storage power stations supply peak demands

The increasing demand for peaking power has resulted in a greater need for pumped storage power stations. This is particularly so where storage lakes already exist, as pre-construction planning can be avoided and less building is required. In response to this need, Voith Siemens Hydro supplied equipment for the extension of two stations in Austria. However, with each project differing drastically from the other, Voith Siemens Hydro had to access each station individually to determine its independent needs.

Synoptic and regional patterns of heavy precipitation in Austria

Seven synoptic patterns responsible for heavy precipitation in Austria were identified with a trajectory clustering method. Back trajectories at different levels, at different times during each day, and from different locations in Austria were utilised together with one potential vorticity value. In addition, seven regions within Austria with similar daily precipitation were identified. The response of heavy precipitation in each of these regions to the synoptic patterns was studied. The results correspond to the synoptic experience and reflect known meteorological situations, such as southerly and northerly Stau or the Vb pattern. The analyses are based on the 15-year re-analysis of the ECMWF (1979–1993), used to calculate the back trajectories, and daily precipitation sums of 131 climate stations in Austria. This paves the way to future applications in climate change research, as the necessary input data are also available from global climate models. The clustering was performed with a promising new procedure, a combination of hierarchical and iterative (K-means) clustering.

Regional, seasonal and predictor-optimized downscaling to provide groups of local scale scenarios in the complex structured terrain of Austria

The aim of this study is to derive local scale climate change scenarios for temperature and precipitation at approximately thirty stations in Austria and to discuss the scenarios' dependency on combinations of large scale fields used as predictors in empirical downscaling. We distinguish between the seasons and different climatic provinces in Austria. To accomplish this task we utilize large scale, monthly NCEP/NCAR reanalysis data and station data provided by the Austrian weather service for the second half of the 20th century. These datasets are analyzed by means of Empirical Orthogonal Functions (EOF) and combined via transfer functions derived by Canonical Correlation Analysis (CCA). The performance of the transfer functions is validated in several validation experiments and used to determine a group of best performing large scale predictors. These predictors are extracted from the IS92a 'greenhouse gas only' (GHG) and IS92a 'greenhouse gas plus aerosols' (GHG+ars) scenarios, performed with the ECHAM4/OPYC3 climate model for the first half of the 21st century and projected onto the local scale by the transfer functions. We discuss the local scale impact of different predictors. In order to assess the bulk properties of these ensembles, those variables which generate the wettest/driest or coolest/warmest changes are further discussed. All changes mentioned below refer to scenarios for the first half of the 21st century compared to observations recorded during the second half of the 20th century. Findings depend on seasons, regions and the scenario actually used. In the case of temperature and the IS92a GHG scenario an overall increase of about 1° to more than 3°C is found. The temperature increase introduced by the IS92a GHG+ars scenario shows around 0.8°C lower values. Differences between the warm and cool realizations are in the same range. In the case of precipitation the performance of the empirical models is substantially lower. For the IS92a GHG differences between wet and dry realizations are in some cases large and do not even allow to define the sign of change. The range of the IS92a GHG+ars ensemble is smaller and indicates moderate seasonal precipitation reductions. Possible reasons that may cause different local scale responses are discussed and an approach of how to deal with them, based on BUSUIOC and VON STROCH, (1996), is proposed.