The hydrological response of the Ourthe catchment to climate change as modelled by the HBV model

The Meuse is an important river in Western Europe, which is almost exclusively rain-fed. Projected changes in precipitation characteristics due to climate change, therefore, are expected to have a considerable effect on the hydrological regime of the river Meuse. We focus on an important tributary of the Meuse, the Ourthe, measuring about 1600 km2. The well-known hydrological model HBV is forced with three high-resolution (0.088°) regional climate scenarios, each based on one of three different IPCC CO2 emission scenarios: A1B, A2 and B1. To represent the current climate, a reference model run at the same resolution is used. Prior to running the hydrological model, the biases in the climate model output are investigated and corrected for. Different approaches to correct the distributed climate model output using single-site observations are compared. Correcting the spatially averaged temperature and precipitation is found to give the best results, but still large differences exist between observations and simulations. The bias corrected data are then used to force HBV. Results indicate a small increase in overall discharge, especially for the B1 scenario during the beginning of the 21st century. Towards the end of the century, all scenarios show a decrease in summer discharge, partially because of the diminished buffering effect by the snow pack, and an increased discharge in winter. It should be stressed, however, that we used results from only one GCM (the only one available at such a high resolution). It would be interesting to repeat the analysis with multiple model

Effecten van landgebruiksveranderingen op gemiddelde en extreme afvoer in het Rijnstroomgebied

Recentelijk heeft veel onderzoek plaatsgevonden om de invloed van klimaatverandering te kwantificeren. Dit kan op verschillende manieren gebeuren, bijvoorbeeld kan er op basis van gemeten data een extreme-waardenverdeling worden geëxtrapoleerd. Een dergelijke aanpak heeft als nadeel dat de aanpak gebaseerd is op statistische kenmerken van het huidige klimaat, terwijl die juist waarschijnlijk veranderen. Een andere mogelijkheid is daarom het doorberekenen van klimaatscenario's zoals die worden gegenereerd met klimaatmodellen. Het landoppervlaktemodel dat in deze studie is gebruikt, namelijk het Variable Infiltration Capacity (VIC) model maakt gebruik van statistische parameters voor de invloed van verzadigde bodems. Het gebied betreft de substroomgebieden van Ruhr, Lahn, Mosel, Main en Necka

Correlation of psychomotor findings and the ability to partially weight bear

<p>Abstract</p> <p>Background</p> <p>Partial weight bearing is thought to avoid excessive loading that may interfere with the healing process after surgery of the pelvis or the lower extremity. The object of this study was to investigate the relationship between the ability to partially weight bear and the patient's psychomotor skills and an additional evaluation of the possibility to predict this ability with a standardized psychomotor test.</p> <p>Methods</p> <p>50 patients with a prescribed partial weight bearing at a target load of 15 kg following surgery were verbally instructed by a physical therapist. After the instruction and sufficient training with the physical therapist vertical ground reaction forces using matrix insoles were measured while walking with forearm crutches. Additionally, psychomotor skills were tested with the Motorische Leistungsserie (MLS). To test for correlations Spearman's Rank correlation was used. For further comparison of the two groups a Mann-Withney test was performed using Bonferroni correction.</p> <p>Results</p> <p>The patient's age and body weight significantly correlated with the ability to partially weight bear at a 15 kg target load. There were significant correlations between several subtests of the MLS and ground reaction forces measured while walking with crutches. Patients that were able to correctly perform partial weight bearing showed significant better psychomotor skills especially for those subtests where both hands had to be coordinated simultaneously.</p> <p>Conclusions</p> <p>The ability to partially weight bear is associated with psychomotor skills. The MLS seems to be a tool that helps predicting the ability to keep within the prescribed load limits.</p

Spatiotemporal Interpolation of Elevation Changes Derived from Satellite Altimetry for Jakobshavn Isbrae, Greenland

Estimation of ice sheet mass balance from satellite altimetry requires interpolation of point-scale elevation change (dHdt) data over the area of interest. The largest dHdt values occur over narrow, fast-flowing outlet glaciers, where data coverage of current satellite altimetry is poorest. In those areas, straightforward interpolation of data is unlikely to reflect the true patterns of dHdt. Here, four interpolation methods are compared and evaluated over Jakobshavn Isbr, an outlet glacier for which widespread airborne validation data are available from NASAs Airborne Topographic Mapper (ATM). The four methods are ordinary kriging (OK), kriging with external drift (KED), where the spatial pattern of surface velocity is used as a proxy for that of dHdt, and their spatiotemporal equivalents (ST-OK and ST-KED)

Simulating Rhine river discharges using a land surface model

The Rhine basin will shift from a combined rainfall and snow melt regime to a more rainfall dominated regime, resulting in increased flood risk in winter and a higher probability of extensive droughts in summer. To be prepared for these projected changes, a thorough understanding of the impacts of climate change to the hydrological regime is necessary. A model has been presented at CAIWA conference at Basel, 12-15 November 2007