Introduction

The driver for OASIS : driver2oasis.f90

This code simulates an atmospheric model which would provide provide data for ORCHIDEE through OASIS.

As the original ORCHIDEE driver (dim2_driver.f90) is outdated and inflexible it has been redeveloped here.

For the moment this code only read compressed by gathering forcing files which contain a sufficient amount of meta-data (link to document).

This code is aimed at running only on one processor. It should not be a limiting factor in the execution time as it only reads once the forcing and then only does some simple time interpolations. Furthermore these interpolations are done while ORCHIDEE runs, i.e. it is not blocked by an oasis_get call.

The fields which OASIS exchanges between the atmosphere and the surface

From the atmosphere to ORCHIDEE

Name	units	ID on driver side	ID on ORCHIDEE side
Height of T and Q	m	ZLTQDRIV	HEIGHTTQ
Height of wind	m	ZLUVDRIV	HEIGHTUV
Atmospheric temperature	K	TAIRDRIV	TEMPLEV1
Atmospheric moisture	kg/kg	QAIRDRIV	HUMILEV1
Rainfall	kg/m2/s	RAINDRIV	RAINFALL
Snowfall	kg/m2/s	SNOWDRIV	SNOWFALL
Downward solar radiation	W/m2	SWDODRIV	SHOWDOWN
Downward longwave radiation	W/m2	LWDODRIV	LONWDOWN
Solar angle	??	SOLADRIV	SOLARANG
Eastward atmsopheric wind	m/s	UWINDRIV	EASTWIND
Northward wind	m/s	VWINDRIV	NORTWIND
Surface pressure	Pa	PRESDRIV	SURFPRES

From the surface to the atmosphere

Name	units	ID on driver side	ID on ORCHIDEE side
Surface evaporation	??	EVAPDRIV	TOTEVAPS
Sensible heat flux	W/m2	SENSDRIV	FLUXSENS
Latent heat flux	W/m2	LATEDRIV	FLUXLATE
Diffuse freshwater flux to the oceans	??	COASDRIV	COASTFLO
River flux into the ocean	??	RIVEDRIV	RIVERFLO
Net CO2 flux	??	NECODRIV	FLUNECO2
??	??	LUCODRIV	FLULUCO2
Surface radiative temperature	K	TRADDRIV	TSURFRAD
Surface temperature	K	TNEWDRIV	TSURFNEW
Surface humidity	kg/kg	QSURDRIV	QSURFNEW
Near Infra-red albedo	-	ANIRDRIV	ALBEDNIR
Visible albedo	-	AVISDRIV	ALBEDVIS
Surface emissivity	-	EMISDRIV	EMISLONW
Surface roughness	m	ROUGDRIV	ROUGNESS

The "main" which controls the ORCHIDEE execution : orchideeoasis.f90

Execution of the model coupled to the driver

As OASIS is linked into both models (driver2oasis and orchideeoasis) the execution of the coupled model is simply achieved by one mpirun command. It can have the following structure :

mpirun -n $PEDRIV driver2oasis : -n $PEORCH orchideeoasis

where : PEDRIV=1 and PEORCH=$(($NSLOTS-$PEDRIV)), i.e. only one processor is for the driver and all others work on ORCHIDEE.

Execution of the model coupled to WRF