Motivated by recent observations of phase-segregated binary Bose-Einstein condensates, we propose a method to calculate the excess energy due to the interface tension of a trapped configuration. By this method one should be able to numerically reproduce the experimental data by means of a simple Thomas-Fermi approximation, combined with interface excess terms and the Laplace equation. Using the Gross-Pitaevskii theory, we find expressions for the interface excesses which are accurate in a very broad range of the interspecies and intraspecies interaction parameters. We also present finite-temperature corrections to the interface tension which, aside from the regime of weak segregation, turn out to be small.

CapsuleState-of-the-Art statistical postprocessing techniques for ensemble forecasts are reviewed, together with the challenges posed by a demand for timely, high-resolution and reliable probabilistic information. Possible research avenues are also discussed.

Linear post-processing approaches are proposed and fundamental mechanisms are analyzed by which the probabilistic skill of an ensemble forecast can be improved. The ensemble mean of the corrected forecast is a linear function of the ensemble mean(s) of the predictor(s). Likewise, the ensemble spread of the corrected forecast depends linearly on that of the uncorrected forecast. The regression coefficients are obtained by maximizing the likelihood function for the error distribution. Comparing different calibration approaches on simple systems that exhibit chaotic features (the Kuramoto-Sivashinsky equation, the spatially extended Lorenz system), four correction mechanisms are identified: the ensemblemean scaling and nudging using the predictor(s), and the ensemble-spread scaling and nudging. Ensemble-spread corrections turn out to yield improvement only when 'reliability' constraints are imposed on the corrected forecast. First of all climatological reliability is enforced and is satisfied when the total variability of the forecast is equal to the variability of the observations. Second, ensemble reliability or calibration of the ensembles is enforced such that the squared error of the ensemble mean coincides with the ensemble variance.In terms of continuous ranked probability skill score, spread calibration provides much more gain in skill than the traditional ensemble-mean calibration and extends for lead times far beyond the error-doubling time. The skill performance is better than or as good as the benchmark calibration method which derives from statistical assumptions -non-homogeneous Gaussian regression. In addition to the member-by-member nature of the approach, benefits compared with the benchmark method can be pinpointed. In particular, although the post-processing methods are performed for each lead time, location and variable independently, they preserve the rank correlations and thus take dependencies across space, time, and different variables into account. In addition, higher-order ensemble moments like kurtosis and skewness correspond to those of the uncorrected forecasts.

The interfacial profiles and interfacial tensions of phase-separated binary mixtures of Bose-Einstein condensates are studied theoretically. The two condensates are characterized by their respective healing lengths and £2 and by the interspecies repulsive interaction K. An exact solution to the Gross-Pitaevskii (GP) equations is obtained for the special case I 2/ I 1 = 1/2 and K = 3/2. Furthermore, applying a double-parabola approximation (DPA) to the energy density featured in GP theory allows us to define a DPA model, which is much simpler to handle than GP theory but nevertheless still captures the main physics. In particular, a compact analytic expression for the interfacial tension is derived that is useful for all f ,, | 2, and K. An application to wetting phenomena is presented for condensates adsorbed at an optical wall. The wetting phase boundary obtained within the DPA model nearly coincides with the exact one in GP theory.

Using the regional climate model ALARO-0, the Royal Meteorological Institute of Belgium and Ghent University have performed two simulations of the past observed climate within the framework of the Coordinated Regional Climate Downscaling Experiment (CORDEX). The ERA-Interim reanalysis was used to drive the model for the period 1979-2010 on the EURO-CORDEX domain with two horizontal resolutions, 0.11 and 0.44 •. ALARO-0 is char-acterised by the new microphysics scheme 3MT, which allows for a better representation of convective precipitation. In Kotlarski et al. (2014) several metrics assessing the performance in representing seasonal mean near-surface air temperature and precipitation are defined and the corresponding scores are calculated for an ensemble of models for different regions and seasons for the period 1989-2008. Of special interest within this ensemble is the ARPEGE model by the Centre National de Recherches Météorologiques (CNRM), which shares a large amount of core code with ALARO-0. Results show that ALARO-0 is capable of representing the European climate in an acceptable way as most of the ALARO-0 scores lie within the existing ensemble. However, for near-surface air temperature, some large biases, which are often also found in the ARPEGE results, persist. For precipitation , on the other hand, the ALARO-0 model produces some of the best scores within the ensemble and no clear resemblance to ARPEGE is found, which is attributed to the inclusion of 3MT. Additionally, a jackknife procedure is applied to the ALARO-0 results in order to test whether the scores are robust , meaning independent of the period used to calculate them. Periods of 20 years are sampled from the 32-year simulation and used to construct the 95 % confidence interval for each score. For most scores, these intervals are very small compared to the total ensemble spread, implying that model differences in the scores are significant.

We argue that, for the recent experiments with imbalanced fermion gases, a temperature difference may occur between the normal (N) and the gapped superfluid (SF) phase. Using the mean-field formalism, we study particle scattering off the N-SF interface from the deep BCS to the unitary regime. We show that the thermal conductivity across the interface drops exponentially fast with increasing h/k B T , where h is the chemical potential imbalance. This implies a blocking of thermal equilibration between the N and the SF phase. We also provide a possible mechanism for the creation of gap oscillations (FFLO-like states) as seen in recent studies on these systems.

Orography is known to affect local meteorological conditions by inducing orographic rainfall and a rain shadow i.e. reduced rainfall on the mountain's leeside with respect to the windward side. Therefore it has a strong effect on the local population and agriculture. Recent work highlights the ambiguities in the definition and difficulties in quantification of the rain shadow effect using observational data. A statistical approach is presented that allows its investigation based on climatological model data in geographically complex regions. This approach requires gridded rainfall and wind along with the model topography. The statistical aspects that contribute to the rainfall enhancement at the windward side are disentangled. These include, for windward and leeward events separately: frequency of occurrence, rainfall-event frequency, rainfall depth per event. By spatial aggregation the regional dependence of these statistics are calculated and visualized. The approach is used to characterize summer rain over the Ethiopian Highlands based a 21year long simulation with the regional climate model ALARO-0 at 4 km resolution. There is an overall increased rainfall of 40% for windward events as compared to leeward events, but regionally this can exceed 150%. This increase can be attributed to the positive differences between windward and leeward events in their frequency of occurrence (on average 20%), and, in the rainfall per rainfall event (on average 16%). Mapped rain shadows correspond well to earlier qualitative observations and the small differences in probability of precipitation confirm that the mechanisms underlying the shadow effect are more complex than the textbook explanation.

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