Results 101 to 110 of about 82,462 (247)

Comparison of two numerical weather prediction models in simulating south foehn in the Alpine Rhine Valley

Quarterly Journal of the Royal Meteorological Society, EarlyView.
ICON outperforms COSMO in simulating a south foehn event in the Alpine Rhine Valley, with improved accuracy in temperature, wind speed, and foehn timing. This enhanced performance likely results from a more accurate representation of surface energy balance and gravity wave pattern on the lee side of the mountain.
Yue Tian, Julian Quimbayo Duarte, Shweta Singh, Juerg Schmidli   +3 more
wiley   +1 more source

Galerkin/Runge-Kutta discretizations for semilinear parabolic equations [PDF]

A new class of fully discrete Galerkin/Runge-Kutta methods is constructed and analyzed for semilinear parabolic initial boundary value problems. Unlike any classical counterpart, this class offers arbitrarily high, optimal order convergence.
Keeling, Stephen L.
core   +1 more source

Simulating the year to minute wind spectrum with mesoscale‐coupled large‐eddy simulations

Quarterly Journal of the Royal Meteorological Society, EarlyView.
We coupled a large‐eddy simulation (resolution 50 m) to a mesoscale model (resolution 2 km), which takes boundary conditions from the ERA5 reanalysis. When using a large enough mesoscale domain (𝒪(1000 km)), the simulation setup can reproduce the observed temporal wind spectrum reasonably at all scales between one year and one minute. Furthermore, such
Bernard Postema, Chiel C. van Heerwaarden, Bart J.H. van Stratum, Pim van Dorp, Peter Baas, Harm J.J. Jonker   +5 more
wiley   +1 more source

Solving Linear Boundary Value Problem Using Shooting Continuous Explicit Runge-Kutta Method

Ibn Al-Haitham Journal for Pure and Applied Sciences, 2017
  In this paper we shall generalize fifth explicit Runge-Kutta Feldberg(ERKF(5)) and Continuous explicit Runge-Kutta (CERK) method using shooting method to solve second order boundary value problem  which can be reduced to order one.These methods we ...
Madeha Sh. Yousif, Bushra E. Kashiem
doaj  

Factorized Runge–Kutta–Chebyshev Methods

Journal of Physics: Conference Series, 2017
The second-order extended stability Factorized Runge-Kutta-Chebyshev (FRKC2) class of explicit schemes for the integration of large systems of PDEs with diffusive terms is presented. FRKC2 schemes are straightforward to implement through ordered sequences of forward Euler steps with complex stepsizes, and easily parallelised for large scale problems on
openaire   +3 more sources

A new smoother method for treating different timescales in variational data assimilation for coupled systems

Quarterly Journal of the Royal Meteorological Society, EarlyView.
We propose a new method for treating different timescales in coupled variational data assimilation for atmosphere–ocean models. The approach involves a series of short‐window coupled assimilations (red arrows in the schematic) followed by a long‐window correction to the ocean fields (blue arrow).
Amos S. Lawless, Nancy K. Nichols, Tsz Yan Leung, Shaerdan Shataer   +3 more
wiley   +1 more source

CONSTRUCTION OF SOME IMPLICIT LINEAR MULTI-STEP METHODS INTO RUNGE-KUTTA TYPES METHODS FOR INITIAL VALUE PROBLEMS (IVP) OF FIRST ORDER DIFFERENTIAL EQUATIONS

Academy Journal of Science and Engineering, 2022
Two implicit Hybrid block methods at step length ????=2 and 3 were derived through collocation procedures. The two derived block methods also reconstructed to an equivalent S stage Runge-Kutta type methods for the solution of ????′=????(????,????).
Ademola M Badmus, Mohammed S Mohammed
doaj  

A structurally localized ensemble Kalman filtering approach

Quarterly Journal of the Royal Meteorological Society, EarlyView.
We derive an inherently localized ensemble Kalman filtering (EnKF) approach, avoiding the need for any auxiliary localization technique. The idea is to first use the variational Bayesian optimization to approximate the (continuous) state analysis probability density function (pdf) by a product of independent marginal pdfs corresponding to small ...
Boujemaa Ait‐El‐Fquih, Ibrahim Hoteit   +1 more
wiley   +1 more source

A multimodel intercomparison study of variable‐resolution global models with grid refinement over the Arctic and Antarctic

Quarterly Journal of the Royal Meteorological Society, EarlyView.
We document the protocol and first results from the first ever coordinated multimodel variable‐resolution experiment set with refinement over the polar regions. We find that the refinement generally yields model‐dependent effects. The most consistent improvement is an amelioration of the upper‐level cold bias in the polar regions that translates into ...
Lise Seland Graff, Dörthe Handorf, Raphael Köhler, Xavier Levine, René R. Wijngaard, Gareth J. Marshall, Alexey Yu. Karpechko, Ryan S. Williams, Priscilla A. Mooney   +8 more
wiley   +1 more source

Modeling the Thermal Properties of Hydrogen‐Based Direct Reduced Iron Using Computational Thermodynamics and Machine Learning

steel research international, EarlyView.
Hydrogen‐based direct reduced iron (H‐DRI) melts differently from scrap and carbon‐bearing DRI. This work combines differential scanning calorimetry experiments, FactSage thermodynamics, and simple composition‐based regression to predict solidus, liquidus, heat capacity, and enthalpy for H‐DRI.
Ankur Agnihotri, Petri Sulasalmi, Pasquale Cavaliere, Ville‐Valtteri Visuri   +3 more
wiley   +1 more source