A5019352144- Meteorological Phenomena and Simulations
- Climate variability and models
- Complex Systems and Time Series Analysis
- Hydrology and Drought Analysis
- Oceanographic and Atmospheric Processes
- Forecasting Techniques and Applications
- Wind and Air Flow Studies
- Flood Risk Assessment and Management
- Ecosystem dynamics and resilience
- Theoretical and Computational Physics
- Data Analysis with R
- Ocean Acidification Effects and Responses
- Arctic and Antarctic ice dynamics
- Marine Bivalve and Aquaculture Studies
- Geophysics and Gravity Measurements
- Lightning and Electromagnetic Phenomena
- Atmospheric and Environmental Gas Dynamics
- Plant Water Relations and Carbon Dynamics
- Hydrology and Watershed Management Studies
- Fractal and DNA sequence analysis
- Paleontology and Stratigraphy of Fossils
- Cryospheric studies and observations
- Energy Load and Power Forecasting
- Computational Physics and Python Applications
- Fire effects on ecosystems
Deutscher Wetterdienst
2016-2023
Goethe University Frankfurt
2018-2020
European Centre for Medium-Range Weather Forecasts
2008-2011
University of Reading
2006-2007
Instituto de Física de Cantabria
2004-2007
Agencia Estatal de Meteorología
2004-2006
Universidad de Cantabria
2004-2006
Brachiopod shells are the most widely used geological archive for reconstruction of temperature and oxygen isotope composition Phanerozoic seawater. However, it is not conclusive whether brachiopods precipitate their in thermodynamic equilibrium. In this study, we investigated potential impact kinetic controls on modern by measuring clumped compositions shells. Our results show that depart from equilibrium due to growth rate-induced effects. These departures line with incomplete hydration...
Abstract. Statistical postprocessing of medium-range weather forecasts is an important component modern forecasting systems. Since the beginning data science, numerous new methods have been proposed, complementing already very diverse field. However, one questions that frequently arises when considering different in framework implementing operational relative performance for a given specific task. It particularly challenging to find or construct common comprehensive dataset can be used...
Abstract Rank histograms are often plotted to evaluate the forecasts produced by an ensemble forecasting system—an ideal rank histogram is “flat” or uniform. It has been noted previously that obvious test of “flatness,” well-known χ2 goodness-of-fit test, spreads its power thinly and hence not good at detecting specific alternatives flatness, such as bias over- underdispersion. Members Cramér–von Mises family tests do much better in this respect. An alternative using decompose statistic into...
Statistical and dynamical downscaling methods are tested compared for seasonal precipitation forecasts over Spain from two DEMETER models: the European Centre Medium-Range Weather Forecasts (ECMWF) theUKMeteorological Office (UKMO). The statistical method considered is a particular implementation of standard analogue technique, based on close neighbours predicted atmospheric geopotential humidity fields. Dynamical performed using Rossby Climate Atmospheric model, which has been nested to...
A twentieth century-long coupled atmosphere-ocean regional climate simulation with COSMO-CLM (Consortium for Small-Scale Modeling, Climate Limited-area Model) and NEMO (Nucleus European Modelling of the Ocean) is studied here to evaluate added value marginal seas over continental regions. The interactive coupling seas, namely Mediterranean, North Baltic Seas, atmosphere in region gives a comprehensive modelling system. It expected be able describe climatological features this geographically...
Abstract. The El Niño–Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) are two well-known temporal oscillations in sea surface temperature (SST), which both thought to influence the interannual variability of summer monsoon rainfall (ISMR). Until now, there has been no measure assess simultaneous information exchange (IE) from ENSO IOD ISMR. This study explores source variables (ENSO IOD) one target First, order illustrate concepts quantification two-source IE a target, we use...
Statistical and dynamical downscaling methods are tested compared for seasonal precipitation forecasts over Spain from two DEMETER models: the European Centre Medium-Range Weather Forecasts (ECMWF) UK Meteorological Office (UKMO).The statistical method considered is a particular implementation of standard analogue technique, based on close neighbours predicted atmospheric geopotential humidity fields.Dynamical performed using Rossby Climate Atmospheric model, which has been nested to ECMWF...
Abstract. The frequency of extreme events has changed, having a direct impact on human lives. Regional climate models help us to predict these regional changes. This work presents an atmosphere–ocean coupled system model (RCSM; with the atmospheric component COSMO-CLM and ocean NEMO) over European domain, including three marginal seas: Mediterranean, North, Baltic Sea. To test model, we evaluate simulation more than 100 years (1900–2009) spatial grid resolution about 25 km. was nested into...
Abstract Probabilistic forecasts of atmospheric variables are often given as relative frequencies obtained from ensembles deterministic forecasts. The detrimental effects imperfect models and initial conditions on the quality such can be mitigated by calibration. This paper shows that Bayesian methods currently used to incorporate prior information written special cases a beta-binomial model correspond linear calibration frequencies. These compared with nonlinear technique (i.e., logistic...
Abstract The extreme dependency score (EDS) has been recently proposed as a non‐vanishing measure of skill to verify predictions rare events. An idealized example is employed investigate the properties EDS when probability event happening small, case for paper warns about non‐dependency on false alarms and correct rejections sample size fixed, which encourages hedging. Thus, should not be sole used assess model's performance forecasting (base rate) also analysed. It shown that can written...
Error growth in spatiotemporal chaotic systems is investigated by analyzing the interplay between temporal and spatial dynamics. The correlation localization of relative fluctuations grow decay indicating two different regimes, before after saturation nonlinear effects. This general behavior shown to hold both simple coupled map lattices global weather models. explains increasing or decreasing trends previously observed exponential rate these systems.
The breeding method is a conceptually simple and computationally cheap ensemble generation technique. Bred vectors (BV) are dynamically obtained from the nonlinear model correspond to spatial structures with fast‐growing fluctuations at each time. These have characteristic localized structure, only small number of significant values corresponding leading fluctuation areas. temporal growth BV interacts making structure key factor dynamics. In this paper we introduce new technique, Logarithmic...
Often in climate system studies, linear and symmetric statistical measures are applied to quantify interactions among subsystems or variables. However, they do not allow identification of the driving responding subsystems. Therefore, this study, we aimed apply asymmetric from information theory: axiomatically proposed transfer entropy first principle-based flow detect interactions. As their estimations challenging, initially tested nonparametric estimators like (TE)-binning, TE-kernel, TE...
We study the spatiotemporal dynamics of random spatially distributed noninfinitesimal perturbations in one-dimensional chaotic extended systems. find that an initial perturbation finite size $\epsilon_0$ grows time obeying tangent space dynamic equations (Lyapunov vectors) up to a characteristic $t_{\times}(\epsilon_0) \sim b - (1/\lambda_{max}) \ln (\epsilon_0)$, where $\lambda_{max}$ is largest Lyapunov exponent and $b$ constant. For times $t < t_{\times}$ exhibit spatial correlations...
Abstract. We present a novel approach to characterize and graphically represent the spatiotemporal evolution of ensembles using simple diagram. To this aim we analyze fluctuations obtained as differences between each member ensemble control. The lognormal character these suggests characterization in terms first two moments logarithmic transformed values. On one hand, mean is associated with exponential growth time. other variance accounts for spatial correlation localization fluctuations. In...
We unfold a profound relationship between the dynamics of finite-size perturbations in spatially extended chaotic systems and universality class Kardar-Parisi-Zhang (KPZ). show how this can be exploited to obtain complete theoretical description bred vectors dynamics. The existence characteristic length/time scales, spatial extent correlations tune it, role breeding amplitude are all analyzed light our theory. Implications weather forecasting based on ensembles initial conditions also discussed.
Abstract The Extreme Dependency Score (EDS) has been introduced in the verification of rare events because it does not vanish as other standard scores do. EDS can be written a function base rate and hit rate. This paper analyses its dependency on It is also shown how score encourages hedging. Guidelines are provided to make proper use when verifying performance forecasting system. Copyright © 2009 Royal Meteorological Society
Spatial configuration of initial errors strongly affects predictability space-time chaotic systems. The numerical models can be adjusted by using prepared ensembles conditions. We present a natural way preparing based in finite-amplitude perturbations with varying correlation. This allows one to take into account the underlying dynamics generate spatial correlations from fully correlated (bred vectors) random fluctuations.
Abstract. Statistical Postprocessing of medium-range weather forecasts is an important component modern forecasting systems. Since the beginning data science, numerous new postprocessing methods have been proposed, complementing already very diverse field. However, one questions that frequently arises when considering different in framework implementing operational relative performance for a given specific task. It particularly challenging to find or construct common comprehensive dataset...
Several past summer floods in Central Europe were associated with so-called Vb-cyclones propagating from the Mediterranean Sea north-eastward to Europe.This study illustrates usefulness of parametric transfer entropy measure TE-linear investigating heavy Vb-cyclone precipitation events Odra catchment (Poland).With application approach, we confirm impact on intensification.Moreover, also detect significant information exchange evaporation over European continent along typical pathway.Thus,...
Abstract. The frequency of extreme events has changed, having a direct impact on human lives. Regional climate models help us to predict these regional changes. This work presents an atmosphere-ocean coupled system model (RCSM, with the atmospheric component COSMO-CLM and ocean NEMO) over European domain, including three marginal seas: Mediterranean, North Baltic Seas. To test model, we evaluate simulation more than one hundred years (1900–2009) spatial grid resolution about 25 km. was...
We present an application of the fractal "chaos game representation" method in climatology for characterizing temporal precipitation aggregation patterns. To this aim, we establish analogy with linguistic analysis considering as a discrete variable (e.g. rain, no rain). Each weekly, or monthly, symbolic sequence observed is then considered "word" and climatological time series at particular gauge defines "language." The distribution different words within language characterizes scheme. In...