2 citations · 2 across the 1 of their papers we have counts for
3 papers
physics.data-an2020★ 2 cited
What limits the number of observations that can be effectively assimilated by EnKF?
Daisuke Hotta, Yoichiro Ota
The ability of ensemble Kalman filter (EnKF) algorithms to extract information from observations is analyzed with the aid of the concept of the degrees of freedom for signal (DFS).…
physics.ao-ph2019
Elimination of spectral blocking by ensuring rotation-free property of discretised pressure gradient within a spectral semi-implicit semi-Lagrangian global atmospheric model
Masashi Ujiie, Daisuke Hotta
The widely-adopted discretisation of the horizontal pressure gradient term formulated by Simmons and Burridge (1981) for atmospheric models on - hybrid vertical coordinate is…
physics.ao-ph2017
A nestable, multigrid-friendly grid on a sphere for global spectral models based on Clenshaw-Curtis quadrature
Daisuke Hotta, Masashi Ujiie
A new grid system on a sphere is proposed that allows for straight-forward implementation of both spherical-harmonics-based spectral methods and gridpoint-based multigrid methods.…