Weather
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.
Sven Kotlarski summarizes current research on the fate of surface snow cover and its implications for climate.
The presence of snow cover on the land surface is closely linked to the prevailing climate. Moreover, by modulating surface energy fluxes snow cover is interactively linked to the atmosphere and constitutes an important component of global and regional climate systems. Available observations show a retreat of snow cover on hemispheric scales as a response to global warming, and climate projections consistently indicate a further decrease. Focusing on Europe and especially on the European Alps, this contribution summarizes current research on the fate of surface snow cover and its implications.
Kari Luojus shows the basic approach to apply passive microwave radiometer data for retrieval of terrestrial snow water equivalent.
The presentation shows the basic approach to apply passive microwave radiometer data for retrieval of terrestrial snow water equivalent. It describes the GlobSnowmethodology to combine satellite-based radiometer data with ground-based snow depth observations and a bias-correction approach to improve the satellite-based retrievals. It also presents the historical satellite-based reconstruction of Northern Hemisphere snow mass, from 1980 to present day (published on Nature, Pulliainen et al. 2020). Pulliainen, J., Luojus, K., Derksen, C. et al. Patterns and trends of Northern Hemisphe re snow mass from 1980 to 2018. Nature 581, 294–298 (2020). https://doi.org/10.1038/s41586-020-2258-0
Veronika Hatvan and Andreas Gobiet present model-based tools used at ZAMG for operational avalanche warning services and local avalanche commissions.
While the usage of models for weather forecasting has been long established, the application of snow cover models for operational avalanche warning purposes is still quite novel. In Austria, the national weather service, ZAMG, develops model-based tools for operational avalanche warning services and local avalanche commissions. In particular, a model-chain consisting of a snow cover model and an ensemble of weather models to operationally assess and predict avalanche hazard in a local context is currently developed. The model-chain provides regional avalanche forecasters and local avalanche commissions with continuous, detailed information about the snow cover from the near-past to the nearfuture. This is to enable early warning of exceptional snow cover situations. In this talk we will give an overview on model-based tools for avalanche services and present the local avalanche prediction model and preliminary results of a first test season in more detail.
Alec van Herwijnen gives an overview of recent efforts at the WSL Institute for Snow and Avalanche Research SLF in Davos, Switzerland, to develop models for avalanche forecasting.
In mountain regions in winter, snow avalanches are relatively frequent and widespread. Compared to other gravitational mass movements, such as landslides or debris flows, snow avalanches occur much more frequently and over a broader geographical area. This has enabled avalanche forecasters to gain practical experience and develop rule-based empirical methods to manage the danger of this ubiquitous natural hazard. However, the ability to forecast avalanches, i.e. predicting snow instability in space and time, is limited by current experience-based forecasting practices. Improvements in terms of spatial and temporal resolution can only be made through model development. In this talk, I will give an overview of recent efforts at the WSL Institute for Snow and Avalanche Research SLF in Davos, Switzerland, to develop models for avalanche forecasting - from mechanical models to better understand the fundamental processes leading to avalanche release to snow cover models to provide real-time information on snow stratigraphy and stability.
Gaëlle Kerdraon presents the algorithm of snow/ice detection in the cloud mask and cloud type products of the NWC-SAF and shows some examples.
The first step of the cloud detection during day, is the snow/ice detection on the ground or at the sea surface. The talk will give details of the flag snow/ice in the cloud mask and in the cloud type. The algorithm will then be presented and illustrated by a recent example. The importance of this snow/ice detection will be pointed out for a good cloud detection. Finally, we will explain the limitations of this flag snow/ice.
Niilo Siljamo investigates the quality of H-SAF snow products.
H-SAF satellite snow extent products can be used for many meteorological and hydrological applications, for example as inputs for weather models. What are these products? How good are they? Especially, MSG/SEVIRI (H31) and Metop/AVHRR (H32) products are described with examples and validation results.
Steinar Eastwood presents the OSI-SAF products and shows climatological applications of the data.
The sea ice products from the EUMETSAT Ocean and Sea Ice Satellite Application Facility are widely used. In this presentation the sea ice products will be presented and examples of use in operational numerical weather and ocean modelling will be given.
Roland Winkler talks about rules and regulations that are in place at airports to provide passenger security in harsh winter weather.
The weather still has a major impact on aviation today. Weather forecasts in aviation not only support safety, but also provide important input on the subject of economical air traffic. As part of this presentation, I would like to give a rough overview of how air traffic works in the cold season. I will speak about de- and anti-icing of aircraft and the snow removal in the airside area. Finally, I will show which meteorological products are created to support safe and economical air traffic.