Turco M.,Euro Mediterranean Center on Climate Change |
Sanna A.,Euro Mediterranean Center on Climate Change |
Herrera S.,University of Cantabria |
Llasat M.-C.,University of Barcelona |
Gutierrez J.M.,Institute Fisica Of Cantabria Ifca
Climatic Change | Year: 2013
In this paper we analyze some caveats found in the state-of-the-art ENSEMBLES regional projections dataset focusing on precipitation over Spain, and highlight the need of a task-oriented validation of the GCM-driven control runs. In particular, we compare the performance of the GCM-driven control runs (20C3M scenario) with the ERA40-driven ones ("perfect" boundary conditions) in a common period (1961-2000). Large deviations between the results indicate a large uncertainty/bias for the particular RCM-GCM combinations and, hence, a small confidence for the corresponding transient simulations due to the potential nonlinear amplification of biases. Specifically, we found large biases for some RCM-GCM combinations attributable to RCM in-house problems with the particular GCM coupling. These biases are shown to distort the corresponding climate change signal, or "delta", in the last decades of the 21st century, considering the A1B scenario. Moreover, we analyze how to best combine the available RCMs to obtain more reliable projections. © 2013 Springer Science+Business Media Dordrecht.
Lopez J.M.,Institute Fisica Of Cantabria Ifca |
Pradas M.,University of Barcelona |
Pradas M.,Imperial College London |
Hernandez-Machado A.,University of Barcelona
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2010
We investigate the complex spatiotemporal dynamics in avalanche driven surface growth by means of scaling theory. We study local activity statistics, avalanche kinetics, and temporal correlations in the global interface velocity, obtaining different scaling relationships among the involved critical exponents depending on how far from or close to a critical point the system is. Our scaling arguments are very general and connect local and global magnitudes through several scaling relationships. We expect our results to be applicable in a wide range of systems exhibiting interface kinetic roughening driven by avalanches of local activity, either critical or not. As an example we apply the scaling theory to analyze avalanches and roughening of forced-flow imbibition fronts in excellent agreement with phase-field numerical integrations. © 2010 The American Physical Society.
Calderon A.,Institute Fisica Of Cantabria Ifca
Nuovo Cimento della Societa Italiana di Fisica C | Year: 2014
We present the most recent studies of diboson production and electroweak physics in proton-proton collisions at 7TeV and 8TeV center-of-mass energy based on data recorded by the CMS detector at the LHC in 2011 and 2012. These include precise measurements of γγ, ZZ and WZ production. Results on triboson production of WWγ and WZγ are also presented. The results are interpreted in terms of constraints on anomalous triple or quartic gauge couplings. We also review some recent electroweak physics results, including the purely electroweak Z bosons production cross section and the muon charge asymmetry measurement. The results are compared with Standard Model prediction. © CERN on behalf of the CMS Collaboration.
Rodriguez M.A.,Institute Fisica Of Cantabria Ifca
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2015
The low-frequency cutoff paradox occurring in 1/f processes has been revisited in a recent Letter [M. Niemann, H. Kantz, and E. Barkai, Phys. Rev. Lett. 110, 140603 (2013)PRLTAO0031-900710.1103/PhysRevLett.110.140603]. A model of independent pulses exhibiting an integrable 1/fβ power spectrum with β>1 explains this paradox. In this paper we explore a complementary possibility based on the use of multiplicative models to generate integrable 1/fβ processes. Three distinct types of models are considered. One of the most used methods of generating 1/f processes based on correlated pulses is among these models. Consequently we find that, contrary to what is generally thought, the low-frequency cutoff is not necessary to avoid the postulated divergence in a wide variety of processes. © 2015 American Physical Society.
Picallo C.B.,Institute Fisica Of Cantabria Ifca |
Picallo C.B.,University of Cantabria |
Lopez J.M.,Institute Fisica Of Cantabria Ifca |
Zapperi S.,CNR Institute for Energetics and Interphases |
Alava M.J.,Aalto University
Physical Review Letters | Year: 2010
We introduce a lattice model able to describe damage and yielding in heterogeneous materials ranging from brittle to ductile ones. Ductile fracture surfaces, obtained when the system breaks once the strain is completely localized, are shown to correspond to minimum energy surfaces. The similarity of the resulting fracture paths to the limits of brittle fracture or minimum energy surfaces is quantified. The model exhibits a smooth transition from brittleness to ductility. The dynamics of yielding exhibits avalanches with a power-law distribution.