Decadal climate prediction at the BSC

Initialised decadal climate predictions have been made available for users as a potential source of near-term climate information with the aim of supporting climate-related decisions in key economic and societal sectors such as energy, agriculture and insurance. Observed climate variability on the decadal timescale can be described as the superimposition of an anthropogenically-driven trend on natural variability of the climate system. The trend can be considered to be driven by changes in anthropogenic emissions (mainly greenhouse gases and anthropogenic aerosols). Natural variability is generated internally by interactions between and within different components of the climate system (atmosphere, ocean and sea ice) or by external factors such as volcanic eruptions and solar activity. The variability modes on timescales of several years and longer can then provide a source of potential predictability and thus lead to skill of decadal predictions. In this context, there is a growing interest from many stakeholders for climate services on 1-10 year timescales, but some efforts are still needed from the climate science community to assess the forecast quality on such timescales

North Atlantic winter wind storm variability across different time scales

In this thesis atmospheric and oceanic conditions important for the development of wind storms on different time scales are analysed. The potential usefulness and limitations of seasonal prediction models and long-term reanalyses with respect to wind storm frequency is investigated and sources of potential seasonal predictability of wind storm frequency are discussed. On the synoptic scale tropospheric growth conditions such as baroclinicity, latent heat and upper level divergence show greater magnitudes of one standard deviation on average compared to all extra-tropical cyclones. Mid-latitude Rossby waves show generally greater amplitudes for different wave numbers during wind storm events. Greater amplitudes are also found in wave numbers not typically associated with storm track activity. The analysis of extra-tropical cyclones and wind storms on the seasonal scale reveal positive, significant skill for some European regions in state-of-the-art seasonal prediction models. North Atlantic sea surface temperatures (SST) are shown to be a source of seasonal predictability and a potential reason for the achieved skill for wind storm frequency predictions in reanalysis and AMIP-type sensitivity experiments. The role of tropical Pacific and Atlantic SST for the record number of wind storms over the UK in winter 2013/14 is discussed

Contribution of nanoclays to the barrier properties of a model proton exchange membrane for fuel cell application

peer reviewedaudience: researcherDirect methanol fuel cells (DMFCs) that use a proton exchange membrane (PEM) as electrolyte, is a promising alternative source of energy for the future. However, methanol crossover from the anodic side to the cathodic one is a major problem in DMFC. Proper dispersion of layered silicates within the fuel cell membrane has been proposed as a strategy for improving the barrier properties of the membrane. The validity of this approach has been tested in case of a model membrane consisting of phosphotungstic acid doped poly(vinyl alcohol). A solvent casting technique has been used, which allows the nanofiller to be delaminated by an ultrasonic pre-treatment, as confirmed by TEM and XRD analysis. The layered silicates have a favourable impact on the methanol permeability, whose the decrease overcompensates some loss in ionic conductivity

Peptide Receptor Radionuclide Therapy for a Phosphaturic Mesenchymal Tumor.

Tumor-induced osteomalacia is a very rare paraneoplastic syndrome. It can be caused by phosphaturic mesenchymal tumor (PMT), a generally benign tumor that produces fibroblast growth factor 23 (FGF-23), which can cause a severe renal phosphate wasting syndrome. Upon complete surgical removal of the tumor, FGF-23 normalizes and the osteomalacia is cured. In cases in which surgery is not feasible, radiofrequency ablation (RFA) is the treatment of choice. We describe a case with a PMT situated in the sacrum, in close proximity to the sacral plexus. Both surgery and RFA were considered potentially nerve damaging. Since the tumor showed expression of somatostatin receptors, we opted for a peptide receptor radionuclide therapy (PRRT) with 177Lu-DOTATOC. However, the therapy did not show the expected success, since the FGF-23 level had even temporarily increased. The patient was then successfully treated with RFA. A partial remission of the tumor was achieved and FGF-23 levels nearly normalized. Despite some severe neurological side effects, the patient showed a remarkable clinical improvement, with no symptoms of osteomalacia within a few weeks

Multi-network-based diffusion analysis reveals vertical cultural transmission of sponge tool use within dolphin matrilines

Behavioural differences among social groups can arise from differing ecological conditions, genetic predispositions and/or social learning. In the past, social learning has typically been inferred as responsible for the spread of behaviour by the exclusion of ecological and genetic factors. This ‘method of exclusion’ was used to infer that ‘sponging’, a foraging behaviour involving tool use in the bottlenose dolphin (Tursiops aduncus) population in Shark Bay, Western Australia, was socially transmitted. However, previous studies were limited in that they never fully accounted for alternative factors, and that social learning, ecology and genetics are not mutually exclusive in causing behavioural variation. Here, we quantified the importance of social learning on the diffusion of sponging, for the first time explicitly accounting for ecological and genetic factors, using a multi-network version of ‘network-based diffusion analysis'. Our results provide compelling support for previous findings that sponging is vertically socially transmitted from mother to (primarily female) offspring. This research illustrates the utility of social network analysis in elucidating the explanatory mechanisms behind the transmission of behaviour in wild animal populations

Galaxy And Mass Assembly (GAMA) : The mechanisms for quiescent galaxy formation at z<1

© 2016 The Authors. One key problem in astrophysics is understanding how and why galaxies switch off their star formation, building the quiescent population that we observe in the local Universe. From the Galaxy And Mass Assembly and VIsible MultiObject Spectrograph Public Extragalactic Redshift surveys, we use spectroscopic indices to select quiescent and candidate transition galaxies.We identify potentially rapidly transitioning post-starburst (PSB) galaxies and slower transitioning green-valley galaxies. Over the last 8Gyr, the quiescent population has grown more slowly in number density at high masses (M * > 10 11 M ⊙ ) than at intermediate masses (M * > 10 10.6 M ⊙ ). There is evolution in both the PSB and green-valley stellar mass functions, consistent with higher mass galaxies quenching at earlier cosmic times.At intermediatemasses (M * > 10 10.6 M ⊙ ), we find a green-valley transition time-scale of 2.6 Gyr. Alternatively, at z ~ 0.7, the entire growth rate could be explained by fast-quenching PSB galaxies, with a visibility time-scale of 0.5 Gyr. At lower redshift, the number density of PSBs is so low that an unphysically short visibility window would be required for them to contribute significantly to the quiescent population growth. The importance of the fast-quenching route may rapidly diminish at z 10 11 M ⊙ ), there is tension between the large number of candidate transition galaxies compared to the slow growth of the quiescent population. This could be resolved if not all high-mass PSB and green-valley galaxies are transitioning from star forming to quiescent, for example if they rejuvenate out of the quiescent population following the accretion of gas and triggering of star formation, or if they fail to completely quench their star formation

Predicción climática decadal global con el modelo EC-EARTH: avanzando hacia una predicción operativa en tiempo real [Presentación]

Presentación realizada en el VI Simposio Nacional de Predicción "Memorial Antonio Mestre", celebrado en la sede central de AEMET en Madrid del 17 al 19 de septiembre de 2018