The influence of drifting snow on the location of glaciers on western Spitsbergen, Svalbard

On western Spitsbergen, Svalbard, the amount of winter precipitation is insufficient to maintain the present-day mass balance of the local glaciers. Additional snow mass must be added to the precipitation to reach the observed accumulation rates of the glaciers. It was assumed in previous work that this additional mass is transported onto the glaciers by drifting snow and snow avalanches. This study is a first attempt to quantify the amount of snow mass added to the glacier mass balance by wind-transported snow. The wind field over an area of 60 × 50 km2 on western Spitsbergen was simulated for 24 idealized weather types by a mesoscale meteorological model on a 750 m grid. The resulting wind velocities and directions were coupled to a two-level snowdrift model. The model output clearly shows erosion and accumulation areas in the terrain. Comparison with the present glacier locations suggests that the glacier accumulation areas coincide with low wind speeds. Moreover, exposed areas with high wind speeds are mostly glacier-free in reality. Thus, the wind field and corresponding snowdrift gives an indication of the location of the present glaciers on western Spitsbergen

Longyearbyen, Svalbard - Vulnerability and risk management of an arctic settlement under changing climate - a challenge to authorities and experts

Longyearbyen, the administrative centre of the Svalbard archipelago, is facing most types of natural hazards under a changing Arctic climate. The catastrophic avalanche in December 2015 led NGI to review our professional work during 30 years of research and consulting in the community. Hazard zonation in Longyearbyen has been a tool in area planning, not for hazard assessment of developed areas, and mainly done during the early 1990s based on current knowledge and methods. The procedures for avalanche warning in Longyearbyen reflect that avalanche release is primarily a consequence of drifting snow, embedded surface snow and collapse of cornices. The first indication in meteorological data of a change in climate was a heavy rainfall midwinter 1995/96, years before global warming of the Arctic was documented. Field research in the 1990s documented that runout in terms of α-angle is longer in cold regions than in other areas. NGI has advised the local administration to revise the old hazard zones taking changing climate and up-dated knowledge and methods into account. The worst-case scenario in Longyearbyen will be a change towards present-day Norwegian Coastal climate with corresponding large avalanches, as well as increasing depth of the active layer and ditto potential for larger and more frequent debris flows and rockslides. Authorities and experts are facing challenging and difficult decisions concerning hazard zoning in a changing climate, design of mitigative measures, removal of exposed houses and extensive costs

Fonnbu, a new (old) platform for snow and avalanche research.

One of the first tasks of the newly established avalanche group at the NGI in 1973 was the selection of a suitable location for an avalanche research station. The choice was on Grasdalen, north of the Jotunheimen mountains, 1000 m asl., in a valley well known for its avalanche activity and high amounts of snow. The station was ready for use in 1973 and intensive research has been made for more than 20 years before budget constraints decreased the activity in the late 80ies. Main research interest was on snow properties, weather and avalanche relations, avalanche dynamics and snow creep in steep slopes. In connection to the research station the Ryggfonn test site was established in 1979. Two years after the 30 years anniversary party, the station burned down completely in February 2005 due to an electrical failure. Scientific data and results were safe in the NGI archive, but lots of old memorials and instruments were lost. Already on the day after the fire, it was decided to build up a new modern station on the same location. Work started the same summer and in August 2006, the new station was officially opened. The new station features accommodation for up to 15 persons, a combined seminar and living room, offices, workshop and of course a sauna. The station is equipped with a modern weather station that also measures snow temperatures and radiation balance. It is now used for NGI research in connection with the Ryggfonn test site, for avalanche courses and courses arranged by the Norwegian School of Winter Warfare and Norwegian Universities. We would like by this presentation inform about the station and invite international researchers to use the station for their research in Norway

Lactation modifies stress-induced immune changes in laboratory rats.

Lactation and stressor exposure both influence the activity of the immune system, but the interaction of both factors on the immune defense is poorly understood. The aim was therefore to investigate in lactating Long-Evans rats the effect of social stress on aspects of cellular immunity in the blood and mesenteric lymph nodes (MLN). Acute social stress (2h) was induced in lactating and non-lactating female intruders using a confrontation model that yielded into social defeat and increased plasma corticosterone concentrations. Stress as well as lactation had marked effects on the immune system. Acute social stress caused granulocytosis, reduced lymphocyte proliferation, and cytokine production in the blood, but had no significant effects in MLN. In the blood of lactating rats, increased numbers of granulocytes and enhanced phagocytosis, but decreased B cell numbers and reduced IL-2 production was observed. However, in MLN both lymphocyte proliferation and monocyte numbers were increased in lactating rats. The effect of stress on the immune measures was often similar in lactating and non-lactating females, but a few important differences were evident: Only non-lactating animals showed an increase in blood granulocyte numbers and a decrease in IL-2 production in response to stressor exposure. Thus, during lactation, a neuroendocrine status may exist which impedes stress-induced modulations at least of some immune parameters

GIS aided avalanche warning in Norway.

By 2008 detailed avalanche warning for the entire Norway is not available. The Norwegian Meteorological Institute only issues a general warning for large regions of the country for danger level 4 or 5, mainly based on automatic indexes integrated in the meteorological forecasting models. Regional and local avalanche warning are issued by the NGI on request of customers such as the railway or road administration and local communities. The NGI warning projects cover vast areas of several 1000 sq km with a very limited budget, approx. 2 man hours a day. Therefore the workflow has to be extremely efficient from acquiring observation data, evaluation of the situation and sending out the new forecast. It has been an aim to include the entire workflow in an all in one web application. A GIS solution was chosen to integrate all data needed by the forecaster for the avalanche danger evaluation. This interactive system of maps features background information for the entire country such as topographic maps, slope steepness, aspect and hill shade to give a 3D impression of the terrain. In each avalanche warning area, all active avalanche paths are plotted including information on the most wind exposed direction. Each avalanche path is linked to a database generated webpage, which will inform the user on more details on the path, such as fall height, release area elevation, pictures etc. In this way the forecaster easily can get an overview over large areas and can give detailed avalanche warnings to the customer. The system is under constant development and is planned to be completely available on web browser such that no special software is needed on local PCs. Future versions will include interactive access to weather data both as 2D fields as well as time series at selected stations

Biochemical purification and functional characterization of the She RNP complex from S. cerevisiae

Asymmetric mRNA localization is a widely used mechanism to sort cell fate determinants in development. In the budding yeast Saccharomyces cerevisae ASH1 (for 'asymmetric synthesis of HO') mRNA localization to the tip of the growing bud leads to targeting of Ash1p to the daughter cell nucleus prior to cytokinesis and is a prerequisite for proper mating type switching. In a genetic screen 5 SHE (for 'Swi5p-dependent HO expression') genes have been isolated, coding for proteins required for the RNA localization process. SHE1 is equivalent to MYO4, a locus that encodes a member of the class V unconventional myosins. The finding that a motor protein is required for ASH1 mRNA targeting suggested a cytoskeleton-based, active transport mechanism. Functional characterization of the SHE genes in turn established a working model for the 'core She machinery' which implies She1p / Myo4p as the ATP-dependent motor protein, She2p as the ASH1 mRNA-binding protein, and She3p as adapter protein connecting She2p to She1p / Myo4p. She4p has been suggested to function in myosin assembly, whereas She5p is required for cell cycle regulated remodeling of the actin cytoskeleton. In a shared project with C. Kruse we could show that Myo4p trafficking is regulated by the formation of a robust She RNP, and relies on She2p and RNA association. In addition to the She proteins, accessory factors such as Loc1p or Khd1p have been suggested to function in ASH1 mRNA localization though they have not been identified in the genetic screen. Thus, in order to allow a detailed characterization of the ASH1-She RNP ('ribo-nucleoprotein') complex, I initiated a biochemical purification. In order to enrich for the She RNP two myo4p mutants were generated in the myosin ATPase, a domain required for Myo4p force generation. Localization studies reveal that the mutants do not transport ASH1 mRNA anymore to the bud tip but instead accumulate in an intermediate, 'frozen' state in the cytoplasm. Affinity purification was carried out based on the TAP ('tandem affinity purification') protocol, using two alternative bait proteins (She2-TAP or Myo4-TAP). In either case I could purify the core She machinery together with ASH1 mRNA. Further analysis of the She RNP by gel filtration experiments revealed a peak fraction with a molecular weight of approximately 4.5 MDa. Within this fraction I could identify Myo4p, She2p and ASH1 mRNA, arguing for the integrity of a single RNP. In addition to She1-3p mass-spectrometric analysis identified a number of so far unknown proteins, including the kinase Gin4p and the translation inhibitor Eap1p. Eap1p has been of outstanding interest since a systematic RNA localization assay with ash1 mutants that contained premature stop codons inserted at various positions within the coding sequence have revealed severe localization defects, indicating that translation (and translational regulation) is required for correct localization. Eap1p has been characterized as an inhibitor of translation initiation and belongs to the family of 'eukaryotic initiation factor 4E-binding proteins', eIF 4E-BPs. Members of this protein family share a common sequence motif which mediates association with eIF 4E, thereby blocking initiation of translation. Initial studies with D eap1 yeast strains have revealed a defective partial accumulation of Ash1p in mother cell nuclei, whereas ASH1 mRNA localization to the bud tip and total Ash1p levels remained unaffected. This observation prompted me to introduce a new model for ASH1 mRNA localization, including the regulation of translation initiation during cytoplasmic She RNP trafficking to the bud

Integrated Database for Rapid Mass Movements in Norway

Rapid mass movements include all kinds of slides in geological material, snow or ice. Traditionally, information about such events is collected separately in different databases covering selected geographical regions and event types. In Norway the terrain is susceptible to all types of rapid mass movements ranging from single rocks hitting roads and houses to large avalanches and huge rock falls where entire mountainsides collapse into fjords creating flood waves and endangering large areas. In addition, quick clay slides occur in desalinated marine sediments in south eastern and mid Norway. For the authorities and inhabitants of endangered areas, the type of treat is of minor importance and mitigation measures have to consider all types of mass movements. This demand asks for a national overview over all registered slide events that allows fast and easy access to the available data. Therefore an integrated national database for all kind of rapid mass movements was developed. The database is built around the single slide event. Only three data entries are mandatory: Time, location and type of slide. The remaining optional information enables registration of detailed information about the terrain, involved materials and damages. Pictures, movies and other documentation can be uploaded into the database. A web based graphical user interface was developed that allows entering new slides, editing and search for slide events. An integration of the database into a GIS system is currently under development. Datasets from various national sources like the road authorities and geological survey were imported into the database. Today, the database contains 21,000 slide events from the last 500 hundred years covering the entire country. A first analysis of the data shows that most slide registrations cover snow avalanche and rock fall events followed by debris slide events. Most events are registered in the steep fjord terrain of the Norwegian west coast, but major slides are registered all over the country. Avalanches clearly account for most fatalities, while large rock avalanche events causing flood waves are the most severe single events. The data is strongly influenced by the personal engagement of local observers and varying observation routines. This database gives a unique source for statistical analysis of slide events, risk analysis and the relation between slides and climate

Identification of slushflow situations from regional weather models

Slushflows are known phenomena that cause significant problems for settlements and infrastructure in Norway. Even though single events in the same location are rather rare compared to avalanches, slushflows do occur annually on a national scale. Both intensive snowmelt events as well as high amounts of rain on the snow cover can cause slushflows during the whole winter season. In recent years eight fatalities and widespread problems for infrastructure in Norway have increased the focus on slushflows. Early warning criteria based on readily available meteorological, hydrological and snow data need to be identified to allow a nationwide monitoring of potentially critical situations and corresponding locations that might lead to slushflow events. Earlier work focused on input data from meteorological stations. These stations are often located at sea level and give little information on the meteorological conditions in the release and drainage areas in the mountains. During the last decade, regional weather models have been developed that deliver weather prognosis every hour with up to 4 km grid resolution. In Norway, observed precipitation and temperature are interpolated to a one-kilometre grid and used to model snow conditions and snowmelt. This study aims at analysing the available data to identify critical meteorological elements and their thresholds for the release of slushflows. Examples from recent years will be studied also taking into account the development of the snow cover prior to the slushflow events. The results indicate that the available data has a promising ability to identify critical situations on a regional level