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The Greenland ice sheet is an excellent observatory for global climate change. Meltwater from the 1.8 million km2 large ice sheet influences oceanic temperature and salinity, nutrient fluxes and global sea level (IPCC 2013). Surface reflectivity is a key driver of surface melt rates (Box et al. 2012). Mapping of different ice-sheet surface types provides a clear indicator of where changes in ice-sheet surface reflectivity are most prominent. Here, we present an updated version of a surface classification algorithm that utilises NASA’s Moderateresolution Imaging Spectroradiometer (MODIS) sensor on the Terra satellite to systematically monitor ice-sheet surface melt (Fausto et al. 2007). Our aim is to determine the areal extent of three surface types over the 2000–2014 period: glacier ice, melting snow (including percolation areas) and dry snow (Cuff ey & Paterson 2010). Monthly 1 km2 resolution surface-type grids can be downloaded via the CryoClim internet portal (www.cryoclim.net). In this report, we briefly describe the updated classification algorithm, validation of surface types and inter-annual variability in surface types., Programme for Monitoring of the Greenland Ice Sheet (PROMICE)

Since the early 1980s, the Geological Survey of Denmark and Greenland (GEUS) glaciology group has developed automatic weather stations (AWSs) and operated them on the Greenland ice sheet and on local glaciers to support glaciological research and monitoring projects (e.g. Olesen & Braithwaite 1989; Ahlstrøm et al. 2008). GEUS has also operated AWSs in connection with consultancy services in relation to mining and hydropower pre-feasibility studies (Colgan et al. 2015). Over the years, the design of the AWS has evolved, partly due to technological advances and partly due to lessons learned in the field. At the same time, we have kept the initial goal in focus: long-term, year-round accurate recording of ice ablation, snow depth and the physical parameters that determine the energy budget of glacierised surfaces. GEUS has an extensive record operating AWSs in the harsh Arctic environment of the diverse ablation areas of the Greenland ice sheet, glaciers and ice caps [...]. The GEUS AWS model in use now is a reliable tool that is adapted to the environmental and logistical conditions of polar regions. It has a proven record of more than 150 stationyears of deployment in Greenland since its introduction in 2007–2008, and a success rate of c. 90% defined as the fraction of months with more than 80% valid air-temperature measurements over the total deployment time of the 25 stations in the field. The rest of this paper focuses on the technical aspects of the GEUS AWS, and provides an overview of its design and capabilities., Programme for Monitoring of the Greenland Ice Sheet (PROMICE)

In 2007 the Programme for Monitoring the Greenland Ice Sheet (PROMICE) was initiated to observe and gain insight into the mass budget of Greenland ice masses. By means of in situ observations and remote sensing, PROMICE assesses how much mass is gained as snow accumulation on the surface versus how much is lost by iceberg calving and surface ablation (Ahlstrøm et al. 2008). A key element of PROMICE is a network of automatic weather stations (AWSs) designed to quantify components of the surface mass balance, including the energy exchanges contributing to surface ablation (Van As et al. 2013). The use of these AWS observations is not limited to studies of ice-sheet mass balance. PROMICE contributes to CryoNet (www.globalcryospherewatch.org/cryonet), the core network of surface measurement sites of the World Meteorological Organization (WMO) Global Cryosphere Watch. By real-time delivery through WMO, PROMICE observations contribute to improve both operational forecasting and climate analysis in the data-sparse Arctic. The Greenlandic population, highly dependent on accurate forecasting of weather conditions, benefits directly from these real-time observations. For instance, extreme surface wind speeds are a high-risk element in Greenland. The third-highest wind speed observed at the surface of the Earth (93 m/s or 333 km/h), was recorded in a 8–9 March 1972 storm at Thule in North-West Greenland (Stansfield 1972). In this paper, we discuss the extent to which the Greenland ice sheet generates its own near-surface wind field. We use PROMICE data to gain insight into the interaction between air temperature, radiation and gravity-driven katabatic winds. We focus on a particularly powerful spring storm in 2013 that contributed to a fatality on an ice-sheet ski traverse attempt (Linden 2013)., Programme for Monitoring of the Greenland Ice Sheet (PROMICE)

Research Summary We studied the effect on unemployment social welfare dependence of serving a sentence under elec-tronic monitoring rather than in prison, using Danish registry data and two policy shifts that extended the use of electronic monitoring in Denmark. We found electronic monitoring is less harmful than imprisonment, at least for younger offenders, whereas it does not leave older offenders worse off than imprisonment. Policy Implications As the United States moves towards noncustodial alternatives to imprisonment, it makes sense for policy makers to direct their attention to experiences from other contexts. The experiences from Denmark are clear: Electronic monitoring is less harmful than imprisonment to the life course out-comes of offenders. Since electronic monitoring could also very well be less costly for the corrections administrations than imprisonment, efforts to extend the use of electronic monitoring in the United States could be accelerated.

The Greenland ice sheet is losing mass (Barletta et al. 2012) and at least half of this loss is caused by an increase in surface melt (e.g. Tedesco et al. 2013). The other part is caused by increased dynamic mass loss, as marine-terminating glaciers lose resistive stresses (Nick et al. 2009) due to both retreat and meltwater lubrication at the bed (Sasgen et al. 2012). In 2007, the Programme for Monitoring of the Greenland Ice Sheet (PROMICE) was initiated with the aim of gaining an insight into the causes of the ice-mass budget changes based on quantitative observations. This is primarily done by assessing how much mass is gained as snow accumulation on the surface versus how much is lost by calving and surface ablation (Ahlstrøm et al. 2008). PROMICE monitors the surface mass balance by means of automatic weather stations (AWSs) designed to quantify accumulation and ablation, as well as the specific energy sources contributing to ablation. These observations are vital to interpreting the physical mechanisms for ice-sheet response to climate change and for the calibration and validation of both satellite observations and climate models. In the wake of several record-breaking warm summers – increasing surface melt rate and extent (Nghiem et al. 2012) – interest in Greenland’s surface mass balance has increased (Tedesco et al. 2013). Observations of net ablation at PROMICE stations provided in situ confirmation of extreme massloss events in 2010 (Fausto et al. 2012) and 2012, primarily documented by other workers through satellite data. In this paper, we present atmospheric temperatures and surface solar reflectivity (known as albedo) of the Greenland ice sheet in the PROMICE period. Albedo modulates the absorption of solar radiation, which is the primary source of melt energy. It is reported to be decreasing in Greenland in recent years (Box et al. 2012), causing the monitoring of albedo variability to be increasingly important. Air temperatures, besides being stron, Programme for Monitoring of the Greenland Ice Sheet (PROMICE)

We present 17 velocity records derived from in situ stand-alone single-frequency Global Positioning System (GPS) receivers placed on eight marine-terminating ice sheet outlet glaciers in South, West and North Greenland, covering varying parts of the period summer 2009 to summer 2012. Common to all the observed glacier velocity records is a pronounced seasonal variation, with an early melt season maximum generally followed by a rapid mid-melt season deceleration. The GPS-derived velocities are compared to velocities derived from radar satellite imagery over six of the glaciers to illustrate the potential of the GPS data for validation purposes. Three different velocity map products are evaluated, based on ALOS/PALSAR data, TerraSAR-X/Tandem-X data and an aggregate winter TerraSAR-X data set. The velocity maps derived from TerraSAR-X/Tandem-X data have a mean difference of 1.5% compared to the mean GPS velocity over the corresponding period, while velocity maps derived from ALOS/PALSAR data have a mean difference of 9.7%. The velocity maps derived from the aggregate winter TerraSAR-X data set have a mean difference of 9.5% to the corresponding GPS velocities. The data are available from the GEUS repository at doi:10.5280/GEUS000001.©Author(s) 2013., SCOPUS: ar.j, info:eu-repo/semantics/published

Med udgangspunkt i tre personers sygdomsfortællinger handler denne artikel om mennesker med diabetiske fodsår ud fra et patientperspektiv med særligt fokus på de måder, hvorpå sygdom, normalitet og egenomsorg fremstår som en palet af valgmuligheder, den enkelte patient må forholde sig til og handle ud fra. Formålet er at vise, hvordan bestemte opfattelser af diabetes som en sygdom, der relativt let kan reguleres og derfor tillader diabetikeren af leve et næsten normalt liv, får konsekvenser for udvikling og behandling af fodsår. Analysen er inspireret dels af antropologiske studier af diabetespatienter, som netop har påpeget denne særlige normalitetsdiskurs, hvor dét at være en person med diabetes ikke nødvendigvis associeres med at være syg, dels af den hollandske filosof og samfundsforsker Annemarie Mols begreber om valgfrihedens logik og omsorgens logik, som sætter spørgsmålstegn ved det hensigtsmæssige i at påføre individet øget ansvar for egen sygdom. I den forbindelse ønsker vi at pege på personer med diabetiske fodsår som en gruppe af særligt sårbare patienter, der har behov for både omsorg og valgfrihed.

Despite its popularity, Gary Becker’s model of the marriage market does not fully predict empirical correlations between married women’s labor market participation and aggregate divorce rates. In this article, we show how a simple extension of Becker’s model inspired by sociological theory improves the model’s predictive power. We extend Becker’s model to account for matching agents’ preferences for partner specialization, and as a novelty, we introduce a sociologically inspired coordination mechanism for this trait. We show that these extensions of Becker’s model improve its predictive power in terms of explaining empirical trends in divorce rates.

Det kraftige skybrud over København den 2. juli 2011 skabte en lang række uvante situationer, der kunne føre til både sygdomme og ulykker. Ny undersøgelse afdækker nu de mulige sundhedsmæssige påvirkninger, hos de mennesker, der har været direkte påvirket af oversvømmelserne