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Rotated/Tilted Mercator Projection (2011)

2011-09-25T14:24:00Z

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 vectors (so-called "compass"), the transformation of meteorological equations. Finally, coding aspects are shortly (...) - Projections, grids and model resolutions

Geometry package for ALADIN & AROME LAM (Dec 2009)

Patricia — 2009-12-10T12:07:18Z

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 a projection of the earth on a plane with linked functions ensuring a smooth shift between representations. A brief annal will recall few notions and formulae linked to used projections, followed by the (...) - Projections, grids and model resolutions

Graphics about possible future discretizations and resolutions in Arpège and Aladin-France (April 2007)

Patricia — 2007-04-03T13:31:13Z

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 levels Vertical levels cast in Altitude coordinates for all the atmosphere zoom at lowest model levels 46 versus 60 levels 46 versus 70 (...) - Projections, grids and model resolutions

New geometry routines for ALADIN (January 2006)

Jean-Daniel GRIL — 2006-01-19T13:01:20Z

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 are available. - Projections, grids and model resolutions

Les différents types de projection utilisés dans ALADIN (2002)

2002-06-01T10:08:00Z

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) - Projections, grids and model resolutions

SURGERY : to determine a gaussian reduced grid (1999)

1999-01-01T13:05:00Z

This procedure "surgery" is determining the number of longitudes for each latitude of a gaussian reduced grid, defined by : the number of latitudes NDGL, the maximum number of longitudes NDLON, the truncation NSMAX. The job is split in 2 parts : first part is the computation of the Legendre polynomials onto a file (done by Arpege/128 bits) second part is the computation of the reduced grid, after reading the Legendre polynomials file (done by a specific program, adapted from the (...) - Projections, grids and model resolutions

SUBGRID : to define parameters of an ALADIN subgrid (1999)

1999-01-01T12:56:00Z

This procedure defines the two corners (SW and NE) of a subgrid Aladin, given : the native grid parameters, the approximative SW subgrid corner (in degrees) : ZLONU & ZLATU the number of points of the subgrid (for C+I) : IDLUXU & IDGUXU The files location is on andante: /u/mrpm/mrpm602/subgrid example : see namelist namex and run "subgrid namex" Alternatively, if the namelist parameter LLDIAG is set to .TRUE., the procedure will only print out the SW-NE diagonal of the (...) - Projections, grids and model resolutions