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Rasmus Gregersen,1,2 Cathrine Fox Maule,3 Henriette Husum Bak-Jensen,2 Allan Linneberg,3,4 Olav Wendelboe Nielsen,4,5 Simon Francis Thomsen,6 Christian S Meyhoff,2,4,7 Kim Dalhoff,4,8 Michael Krogsgaard,4,9 Henrik Palm,4,9 Hanne Christensen,4,10 Celeste Porsbjerg,4,11 Kristian Antonsen,12 Jørgen Rungby,2,4,13 Steen B Haugaard,2,4,13 Janne Petersen,3,14 Finn E Nielsen1,2 1Department of Emergency Medicine, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 2Copenhagen Center for Translational Research, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 3Center for Clinical Research and Prevention, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 4Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark; 5Department of Cardiology, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 6Department of Dermatology, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 7Department of Anaesthesia and Intensive Care, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 8Department of Clinical Pharmacology, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 9Department of Orthopedics, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 10Department of Neurology, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 11Department of Respiratory Medicine, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 12Executive Board, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 13Department of Endocrinology, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark; 14Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, DenmarkCorrespondence: Rasmus Gregersen, Department of Emergency Medicine, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, NV, 2400, Denmark, Email rasmus.gregersen@regionh.dkPurpose: To present a metropolitan cohort, Bispebjerg acute cohort (BAC), and compare patient characteristics and outcomes with patients from urban and rural hospitals in Denmark.Patients and Methods: We linked data from seven Danish nationwide registries and included all acute contacts to non-psychiatric hospitals in the years 2016– 2018. Acute hospital contacts to Bispebjerg and Frederiksberg Hospital constituted BAC, representing a solely metropolitan/urban catchment area. Patient characteristics and outcomes were compared to the rest of Denmark in an urban cohort (UrC) and a rural cohort (RuC), stratified by visit and hospitalization contact types.Results: We identified 4,063,420 acute hospital contacts in Denmark and BAC constituted 8.4% (n=343,200) of them. BAC had a higher proportion of visits (65.1%) compared with UrC (52.1%) and RuC (45.3%). Patients in BAC more often lived alone (visits: BAC: 34.8%, UrC: 30.6%, RuC: 29.2%; hospitalizations: BAC: 50.8%, UrC: 36.7%, RuC: 37.2%) and had temporary CPR number (visits: BAC: 4.4%, UrC: 1.9%, RuC: 1.6%; hospitalizations: BAC: 1.5%, UrC: 0.9%, RuC: 0.8%). Visit patients in BAC were younger (BAC: 36, UrC: 42, RuC: 45 years, median), more often students (BAC: 18.0%, UrC: 14.0%, RuC: 12.5%), and had more contacts due to infectious diseases (BAC: 19.8%, UrC: 14.1%, RuC: 6.2%) but less due to injuries (BAC: 40.0%, UrC: 43.8%, RuC: 60.7%). Hospitalized patients in BAC had higher median age (BAC: 64, UrC: 61, RuC: 64 years) and fewer were in employment than in UrC (BAC: 26.1%, UrC: 32.1%, RuC: 28.1%). BAC Hospitalizations had a lower death rate within 30 days than in RuC (BAC: 3.0% [2.9– 3.1%], UrC: 3.1% [3.0– 3.1%], RuC: 3.4% [3.3– 3.4%]), but a higher readmission-rate (BAC: 20.5% [20.3– 20.8%], UrC: 17.3% [17.2– 17.4%], RuC: 17.5% [17.5– 17.6%]).Conclusion: Significant differences between BAC, urban, and rural cohorts may be explained by differences in healthcare structure and sociodemographics of the catchment areas.Keywords: emergency medicine, acute care, urban-rural disparities, registry-based research, Danish national registers, epidemiology

The purpose of this study is to investigate if the pathway to reach a 2 degree warmer world influences the regional climate in Europe at the time of 2 degrees of global warming above the pre-industrial level. We have investigated this using climate change data from ensembles of both Global Climate Models and Regional Climate Models. We compare the change of regional temperature in Europe to the global temperature change for different emission scenarios, following the IPCC Representative Concentration Pathways (RCP), to see if the pathway has any influence. We find that there is a small but significant difference in the regional temperature change, but the effect is small compared to internal variability on the timescales involved in reaching +2 degrees for the investigated emission scenarios. From an adaptation point of view, reaching +2 degrees as slowly as possible will obviously allow for a longer time period to implement adaptation measures to mitigate the effect of climate change.

There is a general lack of information about the potential effects of 1.5, 2 or more degrees of global warming on the regional climates within Africa, and most studies that address this use data from coarse resolution global models. Using a large ensemble of CORDEX Africa simulations, we present a pan-African overview of the effects of 1.5 and 2 °C global warming levels (GWLs) on the African climate. The CORDEX simulations, consistent with their driving global models, show a robust regional warming exceeding the mean global one over most of Africa. The highest increase in annual mean temperature is found over the subtropics and the smallest one over many coastal regions. Projected changes in annual mean precipitation have a tendency to wetter conditions in some parts of Africa (e.g. central/eastern Sahel and eastern Africa) at both GWLs, but models\' agreement on the sign of change is low. In contrast to mean precipitation, there is a consistent increase in daily precipitation intensity of wet days over a large fraction of tropical Africa emerging already at 1.5 °C GWL and strengthening at 2 °C. A consistent difference between 2 °C and 1.5 °C warmings is also found for projected changes in annual mean temperature and daily precipitation intensity. Our study indicates that a 0.5 °C further warming (from 1.5 °C–2 °C) can indeed produce a robust change in some aspects of the African climate and its extremes.

The impact of a +2 °C global warming on temperature and precipitation over tropical Africa is examined, based on an ensemble of 12 regional climate model scenario simulations. These 12 scenarios are re-phased so that they all correspond to the same global warming of 2 °C with respect to pre-industrial conditions. The continental temperature increase is above the global average. If heat waves are defined with the same temperature threshold in the reference climate and in the scenario, their frequency increases by a factor of 10. When the temperature threshold is adapted to future conditions, there is still a slight increase in frequency. The average precipitation does not show a significant response, due to model-to-model spread. However two compensating phenomena occur, which are robust among the models: (a) the number of rain days decreases whereas the precipitation intensity increases, and (b) the rain season occurs later during the year with less precipitation in early summer and more precipitation in late summer. Simulated daily temperature and precipitation data are combined in two impact models, one for the hydrology of the Nile and Niger basins, one for the food security of the different countries. They show that the main feature of the climate change is not a continuous trend signal, but an alternation of dry and wet decadal to multidecadal episodes.

A large ensemble of regional climate model projections was investigated regarding if and when they show an emergence of significant climate change signals in seasonal temperature and precipitation within Europe. The influence of the North Atlantic Oscillation (NAO), as simulated in the projections, was investigated. In most parts of Europe, the projections indicate robust emergence of temperature change in the first 2 decades of the 21st century, typically earlier for summer than for winter. For precipitation changes, signals generally emerge much later than for temperature. For Europe as a whole, the precipitation signals tend to emerge some 40 to 60 yr later than the temperature signals. In some sub-regions, robust signals for precipitation are not found within the studied period, i.e. until 2100. Some sub-regions, notably the Mediterranean area and Scandinavia, show different behaviour in some aspects compared to the ensemble-based results as a whole. NAO has some influence on the temperature change signals, which emerge earlier in winter for some models and regions if NAO is accounted for. For summer temperatures, the influence of NAO is less evident. Similarly, for precipitation, accounting for NAO leads to an earlier emergence in some regions and models. Here, we find an impact for both summer and winter.

An ensemble of regional climate model simulations from the European framework project ENSEMBLES is compared with observations of low precipitation events across a number of European regions. We characterize precipitation deficits in terms of two drought indices, the Standardized Precipitation Index and the self-calibrated Palmer Drought Severity Index. Models that robustly describe the observations for the period 1961–2000 in given regions are identified and an assessment of the overall performance of the ensemble is provided. The results show that in general, models capture the most severe drought events and that the ensemble mean model also performs well. Some regions that appear to be more problematic to simulate well are also identified. These are relatively small regions and have rather complex topographical features. The analysis suggests that assessment of future drought occurrence based on climate change experiments in general would appear to be robust. But due to the heterogeneous and often fine-scaled structure of drought occurrence, quantitative results should be used with great care, particularly in regions with complex terrain and limited information about past drought occurrence.

Wind energy resource is subject to changes in climate. To investigate the impacts of climate change on future European wind power generation potential, we analyze a multi-model ensemble of the most recent EURO-CORDEX regional climate simulations at the 12 km grid resolution. We developed a mid-century wind power plant scenario to focus the impact assessment on relevant locations for future wind power industry. We found that, under two greenhouse gas concentration scenarios, changes in the annual energy yield of the future European wind farms fleet as a whole will remain within ±5% across the 21st century. At country to local scales, wind farm yields will undergo changes up to 15% in magnitude, according to the large majority of models, but smaller than 5% in magnitude for most regions and models. The southern fleets such as the Iberian and Italian fleets are likely to be the most affected. With regard to variability, changes are essentially small or poorly significant from subdaily to interannual time scales. ISSN:1748-9326 ISSN:1748-9318

The geothermal heat flux is an important factor in the dynamics of ice sheets; it affects the occurrence of subglacial lakes, the onset of ice streams, and mass losses from the ice sheet base. Because direct heat flux measurements in ice-covered regions are difficult to obtain, we developed a method that uses satellite magnetic data to estimate the heat flux underneath the Antarctic ice sheet. We found that the heat flux underneath the ice sheet varies from 40 to 185 megawatts per square meter and that areas of high heat flux coincide with known current volcanism and some areas known to have ice streams.

Before running climate projections with numerical models it is important to validate their performance under present climate conditions. Within the RiskChange project two high‐resolution regional climate models were run as a perfect boundary experiment over Scandinavia. The simulations are validated with respect to timing, location and intensity of extreme events. The main objective of the RiskChange project (www.riskchange.dhigroup.com) is to establish a consistent scientifically‐based framework for risk‐based design using state‐of‐the‐art knowledge of future changes in climate extreme statistics. Very high resolution is required in impact models that are employed to address particular societal needs and risks in terms of adaptation to future climate challenges, (e.g. future storm surge protection of coastlines and low‐level lands or drainage systems in urban areas). The purpose of this study is to analyse the properties of high‐resolution climate simulations over Scandinavia by testing a hypothesis that dynamic simulations are better at retaining the properties of precipitation, notably precipitation extremes than coarser simulations. When compared to statistical methods the dynamical downscaling has the advantage of retaining the full set of atmospheric variables as well as a physically more realistic description of e.g. complex terrain (e.g. mountain ranges and coastlines) and when the representation and behaviour of extremes are important to be captured in a realistic manner. Here, we present a set of two high‐resolution dynamical downscaling simulations on an 8 km grid. Before performing climate simulations under future emission scenarios, it is crucial to validate the model performance under present‐day climate conditions to identify systematic biases within the models (Jacob et al., 2007) and to evaluate to what degree the models simulate observed weather. This is done by performing a so‐called perfect boundary experiment by dynamically downscaling ERA interim data. The atmospheric models WRF and HIRHAM5 were used as regional climate models (RCMs) in this study. Both models were initialized and driven at their lateral boundaries with ERA‐interim data. The simulation period covers 1989‐2010 with the first year considered spin‐up and discarded. As observational reference we have used both gridded data (EOBS, Haylock et al., 2008) as well as station observations. Various methods are employed to examine the performance of the RCMs behaviour on a seasonal to sub‐daily time scale. Both models exhibit a wet bias of 50‐100 % (1‐3 mm) in seasonal precipitation. This bias is most pronounced during winter. The lower‐resolution reanalysis data underestimates wet‐day precipitation in all four season by 13‐36 % over the selected cities Bergen, Oslo and Copenhagen. The RCM simulations show a reduction of this underestimation and even indicate a sign change in some seasons/locations. A spatio‐temporal evaluation of downscaled precipitation extremes shows that both RCM downscalings are much closer to the observational behaviour. The analysis of higher‐order statistical models indicates that short duration extreme precipitation during summer is better simulated within both models.

The geomagnetic field varies on a variety of time‐ and length scales, which are only rudimentarily considered in most present field models. The part of the observed field that cannot be explained by a given model, the model residuals, is often considered as an estimate of the data uncertainty (which consists of measurement errors and unmodeled signal), and is typically assumed to be uncorrelated and Gaussian distributed. We have applied geostatistical methods to analyze the residuals of the Oersted (09d/04) field model (www.dsri.dk/Oersted/Field models/IGRF 2005 candidates/), which is based on 5 years of Orsted and CHAMP data and includes secular variation and acceleration, as well as low‐degree external (magnetospheric) and induced fields. The analysis is done in order to find the statistical behavior of the space‐time structure of the residuals, as a proxy for the data covariances. Once these are known, they can be used in the modeling process to improve the model, estimate its uncertainty, and eventual...

Compared with many countries, the Scandinavian countries including Denmark are known for their high level of equity. Women comprise roughly 50% of the workforce, inexpensive day care is readily available, and laws regarding maternity leave ensure that women can have children without losing their jobs. But although the general situation in Denmark is good, the situation in academia lags behind. Here the glass ceiling still lies low. On a national level for all sciences, 80% of the scientific staff and 90% of the full professors at the universities are male. This should be compared to the fact that more than half of the university students are female [1]. In physics 97% of the full professors are men, whereas about 20% of PhDs and postdocs are women. Recent studies show that the lack of women in academia is not just an inheritance from the past: among the newly hired university staff, women are still greatly underrepresented [2]. Although it is hard to find concrete evidence of discrimination in individual cases, the overall picture is clear: Women in science are not included in academia in the proportion they should be. If the selection process for permanent positions were unbiased, the gender distribution of the staff with permanent positions would to some extent reflect the gender distribution of the PhDs and postdocs. The Network for Women in Physics in Denmark works toward removing gender barriers in the career paths within physics in Denmark, and to get women fully included in the academic power structure. Equity has come a long way in Denmark. Young women of today have much better career possibilities than their mothers and grandmothers. But full equity has not yet been reached. Women still lag behind at the top—be it in politics, business, industry, or academia. The biggest problem currently in Denmark is probably the reluctance to discuss equity issues. Most (primarily male but also female) Danes are so sure that we have full equity, that they refuse to see gender bias where and when it occurs. Again and again statistics show that women still get less pay than men for the same work on a general level, and that in academia fully qualified women are not hired to the same extent as men. Studies that show bias is most often dismissed by explanations other than gender discrimination. Commonly used excuses for the lack of women in academia are that women do not apply for the available positions, or that women are not interested in working in academia. However, this is not true. So one of the greatest challenges that we, the Network of Women in Physics in Denmark, face is to raise the awareness of equity in a manner that the men in power become interested in and willing to listen to issues concerning gender bias. Not much has changed in the past few years in Denmark since the First IUPAP International Conference on Women in Physics was held, but no major revolution could be expected in such a short time. The percentage of women among the permanent staff in the physics departments at Danish universities is roughly 5%, and the women are unevenly distributed. At the physics department at the second largest university in Denmark (University of Aarhus), there still are no women among the permanent staff. There have, however, been some improvements on a national level in the last couple of years. Two of the larger Danish universities have set concrete goals for the percentage of women among the permanent staff, and one of these has outlined a concrete recruitment policy—and even used it. So it does seem that there is some raised awareness on equity in recent years, but much more can still be done. To work for increasing the number of women in academia and to get women fully included in the academic power structure, the Network of Women in Physics in Denmark is in the process of forming a Nordic Network for Women in Physics, in cooperation with the Women in Physics in Sweden and the Women in Physics in Norway. The number of female physicists with permanent positions at the Nordic universities is so low that it is very difficult for young women to find female role models within their own discipline in their own country. By widening the local networks of female physicists to a Nordic network, the pool of potential role models is increased. An important goal of the Nordic Network will be to create better contacts across the Nordic countries by maintaining a database of female physicists from or working in the Nordic countries.

This Perspective considers how to better use and explore climate model output, considering whether statisticians can help achieve better design of ensembles and interpretation of output. Climate simulation data comprise a range of different phenomena with complex and interacting processes. Yet our understanding of the climate is incomplete despite the huge volumes of data, of which only a small fraction has been explored, and many questions remain, particularly those on the character and origin of uncertainties associated with model simulations and how further modelling efforts can improve understanding. Here, we question whether climate model information could be used more effectively and how so-called 'ensembles of opportunity' should be interpreted. Statisticians can contribute substantially to designing 'smarter' ensemble experiments, improving the distillation of information from ensembles, and helping interpret the relative merits of additional simulations. Future progress may be enhanced by increasing collaborations with statisticians.

The magnetic field observations made at the geomagnetic observatory Brorfelde (BFE), Denmark, are subject to disturbances of several nT caused by two single wire high-voltage DC power lines connecting Scandinavia with Central Europe. We have analysed how the magnetic disturbances relate to the currents in the power lines and found a linear relationship. Using linear regression on carefully selected parts of the available data series we have determined the factors of proportionality. Based on the simple relationship between the currents in the power lines and the observed magnetic disturbances, we have derived a method to correct the observatory data for a significant part of the disturbances. In addition we have investigated the influence of the disturbances on the determination of the K-index of the observatory. We found that the K-index based on the original disturbed data compared to the K-indices calculated from corrected data was different in 4% of the 3-hour intervals for the investigated period.

Few geomagnetic ground observations exist of the Earth’s strongest core field anomaly, the South Atlantic Anomaly(SAA). The geomagnetic repeat station on the island Tristan da Cunha, located half-way between South Africaand South America at 37° 05’ S, 12° 18’ W, is therefore of crucial importance. We have conducted several sets ofrepeat station measurements during magnetically quiet conditions (Kp 2o or less) in 2004. The procedures are describedand the results are compared to those from earlier campaigns and to the predictions of various global fieldmodels. Features of the local crustal bias field and the solar quiet daily variation are discussed. We also evaluatethe benefit of continuous magnetic field recordings from Tristan da Cunha, and argue that such a data set is a veryvaluable addition to geomagnetic satellite data. Recently, funds were set up to establish and operate a magnetometerstation on Tristan da Cunha during the Swarm magnetic satellite mission (2011-2014).

The magnetic crustal thickness of Greenland and the surrounding area is determined by inversion of gridded values of the magnetic radial component as given by the IDEMM model, which is based on CHAMP and Orsted data alone, and by the Comprehensive Model (CM4), which is based on satellite and observatory data.