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Projections, grids and model resolutions

The last articles

Rotated/Tilted Mercator Projection (2011)
Published on 25 September 2011

The rotated/tilted Mercator geometry is introduced. The associated computations are developed. These computations involve formulae for :

– the direct geometric transform,

– the reverse geometric transform,

– the quantities associated to Coriolis force,

– the map factor,

– the transformation of (...)

Geometry package for ALADIN & AROME LAM (Dec 2009)
Published on 10 December 2009
by Patricia

Projections used in ALADIN & AROME limited area models (LAM): Generality & description of the code

(access to French version, pour version française)

This document describes the Fortran package for the management of the “geometry†of the ALADIN & AROME LAM. This “geometry†is (...)

Graphics about possible future discretizations and resolutions in Arpège and Aladin-France (April 2007)
Published on 3 April 2007
by Patricia

Map of ARPEGE horizontal resolution (in km) Truncature T358C2.4 T538C2.4 T799C2.4 for the whole sphere zoomed over Europe Vertical levels cast in Pressure coordinates for all the atmosphere zoom at the tropopause 46 versus 60 levels 46 versus 70 (...)

New geometry routines for ALADIN (January 2006)
Published on 19 January 2006
by Jean-Daniel GRIL

This document explains the new projection routines with an emphasis on bugfixes at the level of Cycle 29.t2 to 30.t1. It explains :

– the new "cadre" for ALADIN files,

– use of NCADFORM key,

– in depth description of parameter setup and checks in sufpg1,

– ...

Both English and French documentions (...)

Les différents types de projection utilisés dans ALADIN (2002)
Published on June 2002

Projections in ALADIN by Jean-Daniel Gril, June 2002 :

– the different projections in ALADIN : secantes, tangentes, stereographic, polaire, ...

– the formulae

– Annex : Lambert(1) and Lambert(2)