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Spaceborne radar altimetry over ice sheets has exclusively focused on assessing volume changes through changes in surface elevation. For use in mass balance calculations, these measurements are supplemented with surface property information derived from regional climate models with limited large‐scale observational validation. Simultaneously, the strength at which a radar signal is reflected from the surface contains information on these same near‐surface properties. Here we show that a quantitative interpretation of European (ESA) CryoSat‐2 and French/Indian (CNES/ISRO) SARAL surface echo powers yields timeseries of pan‐Greenland wavelength‐scale roughness and surface density. Individually, the CryoSat‐2 and SARAL results strive toward providing an observational lens to enhance our current understanding of the surface processes affecting ice sheet mass balance and validate their representation by computational models. Taken together, they highlight how diversity in currently operational and future radar satellite altimetry missions can shed light on near‐surface vertical heterogeneity.

Er is een groeiend besef dat het huidige systeem van landgebruik en hoe we met bodem, water, natuur en klimaat omgaan niet langer kan worden volgehouden en er een transitie moet plaatsvinden. Dit alles is geen nieuws, maar de vraag blijft hoe we die transitie met elkaar gaan waarmaken? Daar gaat het Nationaal Programma Landelijk Gebied ons enorm bij helpen en daar gaat deze webinar over.

The temporal coincidence between the Late Permian mass extinction (LPME) and the emplacement of Siberian Trap basalts suggests a causal link between the two events. Here, we discuss stratigraphic changes of organic and inorganic (including isotopic) geochemical properties of marine sediments across the Permian–Triassic boundary (PTB) in the Hovea-3 core, Western Australia, a key PTB section in the southern Neo-Tethys ocean. These data are compared with published data from the Meishan section, southern China, and from the Opal Creek section in western Canada, providing a view of Tethys and Panthalassa changes at the PTB. Trace metal and N-isotopic data, together with organic matter properties suggest that anoxic conditions were established prior to the LPME, intensified close to the LPME, and continued with photic-zone euxinia into the Early Triassic. For the Hovea-3 section, Re-Os ages confirm Changhsingian (253.5 ± 1.4 Ma) deposition of the dated interval sampled immediately below the stratigraphic level characterized by major lithological and isotopic changes. Evaluation of Re-Os, N, and Hg elemental and isotopic data for Hovea-3 suggests that anoxic conditions in the latest Permian were generally unrelated to direct magmatic contributions. A major increase in the initial Os isotopic ratio of Lower Triassic shales suggest an ~8× increase in the Early Triassic continental runoff, based on moderately conservative assumptions for end-members contributing Os to the Permian–Triassic ocean. Comparison to other PTB sections confirms a global signal of increasing Re/Os ratios in the Late Permian, and major and long-lived changes in the isotopic composition of the post-extinction ocean. A distinct peak in Hg concentrations carrying a volcanic isotopic signature, also identified in other PTB sections, likely represents a major pulse of Siberian Trap volcanism. This Hg peak in the Hovea-3 section, however, is detected above the stratigraphic level containing multiple other w

Background: Over the last two decades an increasing number of countries have legalized euthanasia and physician-assisted suicide (EAS) leading to considerable debate over the inherent ethical dilemmas. Increasing numbers of people with personality disorders, faced with unbearable suffering, have requested and received assistance in terminating their lives. EAS in people with personality disorders has, however, received very sparse attention from clinicians and researchers. In this paper, we examine the literature on the practice and prevalence of EAS in people with personality disorders to date and discuss the associated challenges for research and practice. Methods: Narrative review of the literature combined with the authors' collective experience and knowledge of personality disorders. Results: In six of the eight countries where EAS is currently legal, mental disorders are accepted as disorders for which EAS may be granted. In four of these countries, EAS in minors with mental disorders is also accepted. Our literature search resulted in 9 papers on the subject of EAS in people with personality disorders. These studies suggest that most clinicians who grant EAS have indeed perceived their patients' suffering as chronic, unbearable and untreatable without prospect of improvement. The majority of patients with personality disorders had tried some form of psychotherapy, but very few had received any of the relevant evidence-based treatments. The decision to grant EAS based on a perception of the patient's illness as being untreatable with no prospect of improvement, could, thus, in many cases fail to meet the due care criteria listed in EAS laws. People with personality disorders more often wish for death for extended periods of time than people without these disorders. However, there is ample empirical data to show that suicidal tendencies and behaviour can be treated and that they fluctuate rapidly over time. Conclusions: In light of our findings, we believe that

Understanding the long-term changes in the ice sheets of Greenland and Antarctica has global climate significance, especially on long term global sea level rise predictions. Having validated satellite data on current and recent past changes of the ice sheets are crucial for validating climate and earth system models, and give good opportunities for space geodesy to play an important role for society. Under the ESA Climate Change Initiative two projects on Greenland and Antarctica ice sheet changes are making past and present space measurements of the ice sheets available for use by scientists, stakeholders and the general public. The data are part of a large set of ECV’s (Essential Climate Variables) made available by the ESA Climate Initiative, as a contribution to the global Climate Observing System. The ECV data produced include detailed elevation change data from radar altimetry ice flow velocities from synthetic aperture radar missions, mass changes from GRACE, as well as data of glacier and ice shelf grounding lines and (for Greenland) glacier calving front locations from radar and optical data. In the poster we highlight current CCI results on changes in Greenland, with special focus on 25 year elevation changes from ERS-1, ERS-2, Envisat and CryoSat, as well as the Greenland-wide velocity mapping, and the GRACE mass change results.

A long, unbroken sequence of satellite altimetry elevation changes is an essential climate variable. Here,we present the surface elevation change (SEC) record provided in the ESA Greenland ice sheet CCI project, as 5-year running means spanning back to 1992. The 5-year running mean is chosen to show the imprint of climate change on the Greenland ice sheet surface elevation change and limits the imprint of weather variability. We mainly focus on the novel results from ESA's Cryosat- 2 and the French-Indian SARAL/ALtiKa satellite, as this latest generation of radar altimeters provides new opportunities for monitoring Greenland ice sheet SEC. The orbit of Cryosat-2 enables the generation of a higher temporal-resolution data product from Ku-band radar altimetry; a 2-year running mean SEC. This 2-year product shows the inter-annual variability in weather and its imprint in surface elevation. The observational period of SARAL/ALtiKa satellite has now matured, and an experimental SEC product from Ka-band altimetry is being provided in the Greenland ice sheet CCI. The Kaband radar altimetry is less subject to surface penetration in firn covered areas, and map changes in snowfall in the interior region of the Greenland ice sheet. The Greenland ice sheet CCI now provides 11 maps of Greenland SEC generated from Cryosat-2 or SARAL/ALtiKa data. All giving insight into the complex nature of the changing Greenland ice sheet. The emerging patterns from comparing both Cryosat-2 5- year vs. 2-year SEC and Ku-band vs. Ka-band SEC may relate to the interplay between the surface mass balance and internal ice sheet dynamics.

Satellite altimetry provides the longest continuous record of elevation change for assessing the mass balance of the Antarctic Ice Sheet, providing a unique opportunity to observe the ice sheet's response to changes in atmosphere and ocean over the last few decades. The accuracy of altimetry-measured elevation change, from which this mass balance is derived, is of vital importance for quantifying Antarctica's contribution to sea-level rise, and for understanding the physical processes governing changes of the ice sheet. Studies have shown that the rate of Antarctica's mass loss has accelerated over the last decade, largely a result of accelerated ice flow from the Amundsen Sea sector of West Antarctica. Not all areas of the ice sheet are thinning however. Increases in precipitation have resulted in rapid thickening over parts of East Antarctica, especially in Dronning Maud Land. A key question is how these relatively recent changes contrast against the observed longer-term trend and variability. Observations from overlapping satellite altimeter mission over the last three decades can help to answer this question. Here, we have developed a novel framework for cross-calibrating and synthesizing multimission altimetry records, with a further emphasis on generating state-of-the-art corrections for issues affecting the altimeter measurement (such as surface slope and variations in surface scattering) in order to increase the reliability and accuracy of the full altimetry record. The framework allows us to construct consistent time series at fine spatial and temporal scales for the majority of the ice sheet, with a corresponding assessment of the overall uncertainty of the solutions. We present results detailing the complex long-term pattern of elevation change, observed by the altimeters, and discuss the current improvement and imitations of the altimeter record. This effort will allow us to improve upon existing records of the long-term evolution of the Anta

For the last eight years, the ESA CryoSat-2 Ku-band radar altimeter has been measuring the elevation of the Greenland Ice Sheet. Ku-band enables surface penetration at firn covered areas, which hampers the direct interpretation of surface elevation change from Cryosat-2 and other Ku-band altimeters. However, mapping the changes in penetration depth can provide information on firn stratigraphy. If the physical surface (snow/air interface) of the ice sheet can be determined from an independent source, the differences in the two surfaces may directly be linked to the penetration depth of Ku-band radar altimetry, and hence to the temperature and density of the upper firn. Here, we use independent estimates of the surface elevation changes from the Ka-band radar altimeter (AltiKa) operated onboard the French/Indian satellite SARAL. The higher frequency of Ka-band reduces surface penetration to a minimum and combining the records from both Ku- and Ka-band satellites are the key to utilizing the full potential of CryoSat-2. Hence, providing both high spatial-resolution surface elevation change and insights into changes in firn properties. The interpretation of dual-frequency altimetry is supported by firn modeling. The model has previously been applied to gain mass balance from ICESat and is now updated with a conceptual model for Ku-band radar penetration. Ultimately, a dual-band radar altimeter operating from space may provide ice sheet wide measurements of firn densities, a key parameter in determining direct ice mass balance from satellite altimetry.

This report outlines the airborne field operations with the ESA airborne Ku‐band interferometric radar (ASIRAS) and coincident airborne laser scanner (ALS) to acquire gridded data over Austfonna ice cap in Svalbard for CryoSat‐2 validation, first direct Sentinel‐3A underflight over sea ice in the Fram Strait and additional repeat some previously flown sea tracks in Fram Strait and the Wandel Sea. Vertical photography was acquired during sea ice flights to support analysis of ASIRAS and ALS observations. The airborne campaign took place April 4‐16, 2016, operating out of Svalbard and StationNord. The campaign was coordinated by DTU Space using the Norlandair Twin Otter (TF‐POF). It was partly funded by ESA CryoVEx (Austfonna ice cap flights) and partly by EU FP7 project ICE‐ARC (Fram Strait and Wandel sea ice flights). The mobilization costs were shared equally between the projects.The CryoVEx/ICE‐ARC 2016 campaign was a success and the processed data is of high quality. Preliminary comparisons between CryoSat‐2 and ALS data at Austfonna ice cap, proves the concept of using a gridded ALS data set of lines parallel to CryoSat‐2 ground tracks in areas with varying topography. First direct comparisons of Sentinel‐3A and ALS also show consistent results.