ccdfsections : computes some variables (Uorth, Utang,...) along a section made of Nsec linear segments (multi-variable input file)

Computes temperature, salinity, sig0, sig1, sig2, sig4, Uorth, Utang along a section made of Nsec linear segments (see output attributes). Output variables are a function of X(km), depth(m) and time.

This is the wrapping around the native cdfsections operator assuming its usage is:

cdfsections  Ufile Vfile Tfile larf lorf Nsec lat1 lon1 lat2 lon2 n1
... **[ lat3 lon3 n2 ]** **[ lat4 lon4 n3 ]** ....

CliMAF optional arguments are the ones surrounded with ‘**’.

References : http://www.drakkar-ocean.eu/tools

Provider / contact : climaf at meteo dot fr for the wrapping

Inputs (in the order of CliMAF call): 5 datasets

  • a dataset with salinity, temperature and sea water potential density [T-file]
  • a dataset with zonal velocity component [U-file]
  • a dataset with meridional velocity component [V-file]

Mandatory arguments:

  • larf and lorf : location of X=0 for the X-absice (may be out of section)
  • Nsec : number of segments used to compute the whole section
  • lat1, lat2 : extrema latitudes of the segments (from -90 to 90)
  • lon1, lon2 : extrema latitudes of the segments (from 0 to 360)
  • n1 : number of output points on each segment (you have to give Nsec+1 values of lati/loni and Nsec values of ni)

Optional arguments: [ lat3 lon3 n2 ] [ lat4 lon4 n3 ] ....

  • more_points may be used to pass following keys :
    • lat3, lat4, ... : extrema latitudes of the segments (from -90 to 90)
    • lon3, lon4, ... : extrema latitudes of the segments (from 0 to 360)
    • n2, n3, ... : number of output points on each segment (you have to give Nsec+1 values of lati/loni and Nsec values of ni)

It is recommended to put a lot of points on each section if the aim is to compute X-integrations along the section (10 x the model resolution).

Required files: None

Outputs:

  • main output : a netcdf file for ocean speed orthogonal to the section oriented south-north (variable : Uorth)
  • secondary outputs and their names :
    • Utang : field ocean speed tangential to the section oriented south-north
    • so : field sea water salinity
    • thetao : field sea water potential temperature
    • sig0 : field potential density sigma 0
    • sig1 : field potential density sigma 1
    • sig2 : field potential density sigma 2
    • sig4 : field potential density sigma 4

Climaf call example:: For more examples which are systematically tested, see cdftools_multivar.py

>>> # Use "data_CNRM" project, where netcdf files with values of so, thetao and rhopoto are defined
>>> cdef("project","data_CNRM")
>>> dT=ds(simulation="PRE6CPLCr2alb", variable="so,thetao,rhopoto", period="199807", realm="O")
>>> duo=ds(simulation="PRE6CPLCr2alb", variable="uo", period="199807", realm="O") # dataset with zonal velocity component
>>> dvo=ds(simulation="PRE6CPLCr2alb", variable="vo", period="199807", realm="O") # dataset with meridional velocity component
>>> my_cdfsections=ccdfsections(duo,dvo,dT,larf=48.0,lorf=125.0,Nsec=1,lat1=50.0,lon1=127.0,lat2=50.5,lon2=157.5,n1=20)
>>> cfile(my_cdfsections) # to compute all variables along a section made of Nsec linear segments
>>> Utang_var=my_cdfsections.Utang # Utang_var receives operator output named "Utang", namely the field ocean speed tangential to the section oriented south-north
>>> so_var=my_cdfsections.so # so_var receives operator output named "so"
>>> thetao_var=my_cdfsections.thetao # thetao_var receives operator output named "thetao"
>>> sig0_var=my_cdfsections.sig0 # sig0_var receives operator output named "sig0"
>>> sig1_var=my_cdfsections.sig1 # sig1_var receives operator output named "sig1"
>>> sig2_var=my_cdfsections.sig2 # sig2_var receives operator output named "sig2"
>>> sig4_var=my_cdfsections.sig4 # sig4_var receives operator output named "sig4"
>>> my_cdfsections2=ccdfsections(duo,dvo,dT,larf=48.0,lorf=305.0,Nsec=2,lat1=49.0,lon1=307.0,lat2=50.5,lon2=337.5,n1=20,more_points='40.3 305.1 50')
>>> cfile(my_cdfsections2)

Implementation: The operator is implemented as a script which calls a binary using cdftools cdfsections operator.

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ccdfsectionsm : computes some variables (Uorth, Utang,...) along a section made of Nsec linear segments (mono-variable input file)

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