Results 61 to 70 of about 612,415 (186)

High‐resolution atmospheric CO2 concentration data simulated in WRF‐Chem over East Asia for 10 years

Geoscience Data Journal
In this study, high‐resolution CO2 concentration data were generated for East Asia to analyse long‐term changes in atmospheric CO2 concentrations, as East Asia is an important region for understanding the global carbon cycle.
Min‐Gyung Seo, Hyun Mee Kim, Dae‐Hui Kim   +2 more
doaj   +1 more source

Variational data assimilation using targetted random walks [PDF]

, 2010
The variational approach to data assimilation is a widely used methodology for both online prediction and for reanalysis (offline hindcasting). In either of these scenarios it can be important to assess uncertainties in the assimilated state.
Cotter, S. L., Dashti, M., Robinson, J. C., Stuart, A. M.   +3 more
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A reduced-order strategy for 4D-Var data assimilation [PDF]

, 2005
This paper presents a reduced-order approach for four-dimensional variational data assimilation, based on a prior EO F analysis of a model trajectory. This method implies two main advantages: a natural model-based definition of a mul tivariate background
Bennett, Blayo, Blum, Brasseur, Buehner, C. Robert, Cane, Courtier, D'Andréa, De Witte, Devenon, E. Blayo, F.-X. Le Dimet, Faugeras, Gilbert, Greiner, Greiner, Hoang, Hoteit, Ide, J. Blum, J. Verron, Lawson, Legras, Lellouche, Leredde, Lermusiaux, Lions, Luong, Madec, Moore, Mu, Pham, Rabier, Ricci, S. Durbiano, Schröter, Spitz, Toth, Veersé, Vialard, Vialard, Weaver, Weaver, Wenzel   +44 more
core   +7 more sources

Dynamics and predictability of secondary eyewall formation in sheared tropical cyclones

Journal of Advances in Modeling Earth Systems, 2017
This study examines the predictability and dynamics of tropical cyclone (TC) secondary eyewall formation (SEF), eyewall replacement cycles (ERC), and intensity changes under moderate environmental shear through convection‐permitting ensemble simulations.
Fuqing Zhang, Dandan Tao, Y. Qiang Sun, Jeffrey D. Kepert   +3 more
doaj   +1 more source

Sensitivity And Out-Of-Sample Error in Continuous Time Data Assimilation

, 2011
Data assimilation refers to the problem of finding trajectories of a prescribed dynamical model in such a way that the output of the model (usually some function of the model states) follows a given time series of observations.
Apte, Boccaletti, Bröcker, Cardinali, Courtier, Derber, Hastie, Jazwinsky, Judd, Kierzenka, Le Dimet, Liu, Liu, Lorenz, Lorenz, Nijmeirer, Parlitz, Pereyra, Sage, Seaman, Szendro, Zeitouni, Åström   +22 more
core   +1 more source

Projected Shadowing-Based Data Assimilation [PDF]

SIAM Journal on Applied Dynamical Systems, 2018
In this article we develop algorithms for data assimilation based upon a computational time dependent stable/unstable splitting. Our particular method is based upon shadowing refinement and synchronization techniques and is motivated by work on Assimilation in the Unstable Subspace (AUS) and Pseudo-orbit Data Assimilation (PDA).
De Leeuw, Bart, Dubinkina, Svetlana, Frank, Jason, Steyer, Andrew, Tu, Xuemin, Van Vleck, Erik   +5 more
openaire   +5 more sources

Unveiling Energy Conversions of the Venus Atmosphere by the Bred Vectors

Geophysical Research Letters
The Lorenz energy cycle was often used to analyze energy conversions related to instabilities in planetary atmospheres using zonal means as basic states.
Jianyu Liang, Norihiko Sugimoto, Takemasa Miyoshi   +2 more
doaj   +1 more source

A Practical Method to Estimate Information Content in the Context of 4D-Var Data Assimilation. I: Methodology [PDF]

, 2011
Data assimilation obtains improved estimates of the state of a physical system by combining imperfect model results with sparse and noisy observations of reality. Not all observations used in data assimilation are equally valuable.
Bowman, Kevin, Jardak, Mohamed, Lee, Meemong, Sandu, Adrian, Singh, Kumaresh   +4 more
core   +2 more sources

Variational data assimilation for the initial-value dynamo problem [PDF]

, 2011
The secular variation of the geomagnetic field as observed at the Earth's surface results from the complex magnetohydrodynamics taking place in the fluid core of the Earth.
Andrew Jackson, B. P. Jones, D. Gubbins, G. Backus, G. Evensen, G. W. Hanson, H. K. Moffatt, J. Larmor, J. Nocedal, J. P. Aubin, J. P. Boyd, K. Ito, Kuan Li, M. Kono, O. Talagrand, Philip W. Livermore, R. D. Gibson, R. L. Parker, R. Reed, T. H. Cormen, T. Namikawa, W. Kuang, W. Kuang   +22 more
core   +1 more source

Reduction of complexity and variational data assimilation [PDF]

, 2015
Conferencia plenaria por invitaciónReduced basis methods belong to a class of approaches of \emph{model reduction} for the approximation of the solution of mathematical models involved in many fields of research or decision making and in data ...
Maday, Yvon
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