Glacier projections sensitivity to temperature-index model choices and calibration strategies

The uncertainty of glacier change projections is largely influenced by glacier models. In this study, we focus on temperature-index mass-balance (MB) models and their calibration. Using the Open Global Glacier Model (OGGM), we examine the influence of different surface-type dependent degree-day factors, temporal climate resolutions (daily, monthly) and downscaling options (temperature lapse rates, temperature and precipitation corrections) for 88 glaciers with in-situ observations. Our findings indicate that higher spatial and temporal resolution observations enhance MB gradient representation due to an improved calibration. The addition of surface-type distinction in the model also improves MB gradients, but the lack of independent observations limits our ability to demonstrate the added value of increased model complexity. Some model choices have systematic effects, for example weaker temperature lapse rates result in smaller projected glaciers. However, we often find counter balancing effects, such as the sensitivity to different degree-day factors for snow, firn and ice, which depends on how the glacier accumulation area ratio changes in the future. Similarly, using daily versus monthly climate data can affect glaciers differently depending on the shifting balance between melt and solid precipitation thresholds. Our study highlights the importance of considering minor model design differences to predict future glacier volumes and runoff accurately

The effect of the SAFE or SORRY? programme on patient safety knowledge of nurses in hospitals and nursing homes: a cluster randomised trial

Background: patients in hospitals and nursing homes are at risk for the development of often preventable adverse events. Guidelines for the prevention of many types of adverse events are available, however compliance with these guidelines appears to be lacking. As a result many patients do not receive appropriate care. We developed a patient safety program that allows organisations to implement multiple guidelines simultaneously and therefore facilitates guideline use to improve patient safety. This program was developed for three frequently occurring nursing care related adverse events: pressure ulcers, urinary tract infections and falls. For the implementation of this program we developed educational activities for nurses as a main implementation strategy.Objectives: the aim of this study is to describe the effect of interactive and tailored education on the knowledge levels of nurses.Design: a cluster randomised trial was conducted between September 2006 and July 2008.Settings: ten hospital wards and ten nursing home wards participated in this study. Prior to baseline, randomisation of the wards to an intervention or control group was stratified for centre and type of ward.Participants: all nurses from participating wards.Methods: a knowledge test measured nurses’ knowledge on the prevention of pressure ulcers, urinary tract infections and falls, during baseline en follow-up. The results were analysed for hospitals and nursing homes separately.Results: after correction for baseline, the mean difference between the intervention and the control group on hospital nurses’ knowledge on the prevention of the three adverse events was 0.19 points on a zero to ten scale (95% CI: ?0.03 to 0.42), in favour of the intervention group. There was a statistically significant effect on knowledge of pressure ulcers, with an improved mean mark of 0.45 points (95% CI: 0.10–0.81). For the other two topics there was no statistically significant effect. Nursing home nurses’ knowledge did neither improve (0 points, CI: ?0.35 to 0.35) overall, nor for the separate subjects.Conclusion: the educational intervention improved hospital nurses’ knowledge on the prevention of pressure ulcers only. More research on long term improvement of knowledge is neede

lilianschuster/glacier-model-projections-until2300: v0.1

<p>Glacier model projections until 2300 as we plan to submit to the ICCI State of the cryosphere report 2023</p&gt

Response time sensitivity of glaciers using the Open Global Glacier Model : From idealised experiments to an estimate for Alpine glaciers

Shrinking glaciers are an iconic impact of past and ongoing climate change. Since glaciers adjust slowly to a changing climate, there is an imbalance between the current climate and their geometry: Present and future glacier extent largely depends on past climate variability, turning glaciers into a "delayed" sensor of climate change. A measure that is often used to describe how fast glaciers react to climate change (here defined as a step change in temperature, T) is the e-folding response time, i.e the time in which 63% of the adjustment between an initial and a perturbed equilibrium glacier state occurs. Estimating this response time from known glacier characteristics would be very useful, but this is impeded by the complex non-linear response of glacier dynamics to climate perturbations. Therefore, we rely on a numerical model to attempt to disentangle the factors affecting the e-folding response time. Using the Open Global Glacier Model (OGGM), we perform idealised glacier experiments to estimate the response time sensitivity to climatic or geometric glacier characteristics. Starting with idealised glacier geometries, the experiments are improved to include more realistic and complex bed geometries. We compute the temporal evolution (1862--2003) of the response time of the Hintereisferner, Ötztal Alps, using initial equilibrium glacier states with similar lengths as the observations and the HISTALP climate dataset. Furthermore, we conduct general response time estimates for 3863 alpine glaciers using initial equilibrium glaciers with similar areas as measured in 2003. For a large temperature perturbation T, the response time of the Hintereisferner decreases over time along with decreasing glacier length. For smaller T, the response time is longer, commencing with a slight increase and then followed by a decrease. This initial paradoxical increase is most likely due to melting of the glacier into a bedrock depression. For idealised glaciers of constant width and a single flowline, we could attribute increased response times to such a bedrock depression. The response time of alpine glaciers for smaller T is more variable between the glaciers and mostly longer, for T=+0.1C in median 53 years and 50% of the glaciers between 42 and 121 years compared to for T=+1C in median 20 years and 50% between 14 and 29 years. Moreover, the response time is shorter for steeper glaciers or higher mass balance gradients for alpine glaciers as well as in idealised experiments. For large T=+1C, the response time appears to increase linearly with the mean ice thickness. Glacier size parameters such as volume, area or length do not have a direct influence on the response time of alpine glaciers. Most alpine glaciers are steeper in their upper part, which might explain why applying larger T results in rather shorter response times. This effect is most prominent for flat initial equilibrium glaciers, possibly because the response time is more sensitive to perturbed equilibrium slope changes on flat glaciers compared to already relatively steep glaciers. Besides the large response time sensitivity on the applied perturbation T, we find discrepancies between different model set-ups and studies. Therefore, we conclude that the response time is only a relative measure under simplified "laboratory conditions", and its interpretation as an absolute number is delicate. Despite the vagueness of its definition, it is a simple tool to compare the glaciers response to climatic change and to diagnose which geometric and climatic parameters control the response behaviour. Furthermore, the response time and its changes with T could be used to cluster worldwide glaciers into specific groups of response time, and these insights could improve calibrations of numerical global glacier models. Whether the response time has a predictive value for other aspects of glaciology such as the current rate of volume change has to be studied in the future.Arbeit an der Bibliothek noch nicht eingelangt - Daten nicht geprüftInnsbruck, Univ., Masterarb., 2020(VLID)486445

OGGM/massbalance-sandbox: Version used in Hanus et al. glacier-hydro coupling manuscript

<p>This is the OGGM/massbalance-sandbox version used by @sarah-hanus for her manuscript ("Coupling a large-scale glacier and hydrological model (OGGM v1.5.3 and CWatM V1.08) – Towards an improved representation of mountain water resources in global assessments") that is soon submitted to Geoscientific Model Development (GMD). The branch is identical to the commit: https://github.com/OGGM/massbalance-sandbox/commit/7c055cc96e45389f9d1643cf6b5c28bca643957c</p&gt

Glacier projections sensitivity to temperature-index model choices and calibration strategies

The uncertainty of glacier change projections is largely influenced by glacier models. In this study, we focus on temperature-index mass-balance (MB) models and their calibration. Using the Open Global Glacier Model (OGGM), we examine the influence of different surface-type dependent degree-day factors, temporal climate resolutions (daily, monthly) and downscaling options (temperature lapse rates, temperature and precipitation corrections) for 88 glaciers with in-situ observations. Our findings indicate that higher spatial and temporal resolution observations enhance MB gradient representation due to an improved calibration. The addition of surface-type distinction in the model also improves MB gradients, but the lack of independent observations limits our ability to demonstrate the added value of increased model complexity. Some model choices have systematic effects, for example weaker temperature lapse rates result in smaller projected glaciers. However, we often find counter balancing effects, such as the sensitivity to different degree-day factors for snow, firn and ice, which depends on how the glacier accumulation area ratio changes in the future. Similarly, using daily versus monthly climate data can affect glaciers differently depending on the shifting balance between melt and solid precipitation thresholds. Our study highlights the importance of considering minor model design differences to predict future glacier volumes and runoff accurately.</p

Coupling a large-scale glacier and hydrological model (OGGM v1.5.3 and CWatM V1.08) - Data Set

&lt;p&gt;GENERAL INFORMATION&lt;/p&gt;&lt;p&gt;The data and scripts used for the analysis of the manuscript "Coupling a large-scale glacier and hydrological model (OGGM v1.5.3 and CWatM V1.08) – Towards an improved representation of mountain water resources in global assessments"&lt;/p&gt;&lt;p&gt;&lt;strong&gt;When using this dataset, please refer to the original publication in addition to this Zenodo repository.&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;DATA &amp; FILE OVERVIEW&lt;/p&gt;&lt;p&gt;please have a look at readme.txt&nbsp;&lt;/p&gt;&lt;p&gt;Don't hesitate to contact us in case of any questions ([email protected])&lt;/p&gt