The following MARS requests can be used as a tutorial. The links into the MARS Catalogue might be helpful to create a valid retrieve script. However, the dates might need to be adapted.
As one can very easily retrieve large amounts of data it is best to start mars in a location where plenty of disk space is available, e.g. in $SCRATCH:
cd $SCRATCH |
The solutions below provide valid MARS requests which can be passed to the mars command as
% mars < myrequestfile or % mars myrequestfile |
Retrieve 1000,850,700 and 500 hPa temperatures from the 15th of February 1999 12 UTC Analysis > see in MARS Catalogue
retrieve, class = od, type = an, expver = 1, date = 19990215, time = 12, param = t, levtype = pressure level, levelist = 1000/850/700/500, target = "t.grb" |
Retrieve wind components for tomorrow at 12:00 and 18:00 from yesterday's 12Z forecast at all 137 model levels > see in MARS Catalogue
retrieve, type = forecast, param = u/v, levtype = model level, levelist = 1/to/137, date = -1, time = 12, step = 48/54, target = "wind" |
Retrieve geopotential and surface pressure for yesterday's analysis cycles (00,06,12,18) > see in MARS Catalogue
retrieve, class = od, type = analysis, levtype = surface, date = -1, time = 00/06/12/18, param = z/sp, target = "all.an" |
Retrieve surface pressure and surface thermal radiation downwards at every 12-hour time-step for the 12Z forecast from two days ago > see in MARS Catalogue
retrieve, type = forecast, param = sp/str, date = -2, step = 12/to/240/by/12, time = 12, levtype = sfc, target = "sfc.grb" |
Retrieve the operational monthly mean model level temperature (all levels) from the 06:00 analysis for February 1997 > see in MARS Catalogue
retrieve, class = od, stream = mnth, type = analysis, time = 06, date = 19970200, levtype = model level, param = t, levelist = 1/to/31, target = "monthly" |
Retrieve the temperature on model levels 1, 2 and 3 for yesterday's 12 hour forecast. > see in MARS Catalogue
retrieve, type = fc, date = -1, time = 12, step = 12, levtype = ml, level = 1/2/3, param = t, target = "t_ml_1_2_3" |
Retrieve the 1000 hPa geopotential from yesterday's 12 UTC forecast (> see in MARS Catalogue) for:
the 12 hour forecast
retrieve, type = fc, date = -1, time = 12, step = 12, levtype = pl, level = 1000, param = z, target = "z1000_a" |
the 6, 12, 24 and 48 hour forecasts
retrieve, type = fc, date = -1, time = 12, step = 6/12/24/48, levtype = pl, level = 1000, param = z, target = "z1000_b" |
the 12 hour to 240 hour forecasts at 12 hour intervals
retrieve, type = fc, date = -1, time = 12, step = 12/to/240/by/12, levtype = pl, level = 1000, param = z, target = "z1000_c" |
all forecast time-steps
retrieve, type = fc, date = -1, time = 12, # step = all, # The value "all" is convenient to use but MARS can only report on missing steps if |
Retrieve Total Precipitation, Control forecast overlap
|
Retrieve the 1000,500 and 300 hPa temperatures for today at noon from the 12 UTC forecast of two days ago on an N48 Gaussian Grid > see in MARS Catalogue
retrieve, type = forecast, param = t, date = -2, time = 12, step = 48, grid = 48, levelist = 1000/500/300, levtype = pl, target = "t.gg.grb" |
Retrieve the same on a latitude/longitude grid, 1.5 by 1.5 degrees. > see in MARS Catalogue
retrieve, type = forecast, param = t, date = -2, time = 12, levelist = 1000/500/300, levtype = pl, step = 48, grid = 1.5/1.5, target = "t.ll.grb" |
Retrieve Europe in the same way as in the previous retrieval. Compare the size of the resulting file with the previous one. > see in MARS Catalogue
retrieve, type = fc, param = t, date = -2, time = 12, levelist = 1000/500/300, levtype = pl, step = 48, grid = 1.5/1.5, area = e, target = "t.europe" |
Retrieve the 1000 and 500 hPa geopotential for 1200 yesterday from the analysis in the formats below (one job for each form): > see in MARS Catalogue
leaving the data in its original form
retrieve, type = an, date = -1, time = 12, param = z, levtype = pressure level, level = 1000/500, target = "myfile1" |
reducing the truncation to T106
retrieve, type = an, date = -1, time = 12, param = z, levtype = pressure level, level = 1000/500, resol = 106, target = "myfile1" |
converting the data to a global N48 Gaussian grid
retrieve, type = an, date = -1, param = z, levtype = pressure level, level = 1000/500, grid = 48, target = "myfile1" |
converting the data to a regular 5.0 by 5.0 degree global latitude/longitude grid
retrieve, type = an, date = -1, param = z, levtype = pressure level, level = 1000/500, grid = 5.0/5.0, target = "myfile1" |
converting the data to an N80 Gaussian grid for the European area
retrieve, type = an, date = -1, param = z, levtype = pressure level, level = 1000/500, grid = 80, area = europe, target = "myfile1" |
converting the data to an N80 Gaussian grid for the area from 50 degrees North to 10 degrees North, and 20 degrees West to 20 degrees East
retrieve, type = an, date = -1, param = z, levtype = pressure level, level = 1000/500, grid = 80, area = 50/-20/10/20, target = "myfile1" |
converting the data to the same area but convert it to a 2.5 degree by 2.5 degree latitude/longitude grid
retrieve, type = an, date = -1, param = z, levtype = pressure level, level = 1000/500, grid = 2.5/2.5, area = 50/-20/10/20, target = "myfile1" |
Retrieve surface winds for yesterday's 24 hour forecast on the European area converting to a 0.57 by 0.57 degrees latitude/longitude grid. > see in MARS Catalogue
What happens to the conversion?
retrieve, type = fc, date = -1, time = 12, step = 24, levtype = sfc, param = 10u/10v, area = europe, # As the area is not compatible with the grid, grid = 0.57/0.57, # MARS will expand the area to make it fit. target = "10u_10v" |
Retrieve all the sea surface observations for the 1st February 2015. > see in MARS Catalogue
retrieve, type = ob, |
Retrieve the surface temperature fields of the first 10 members of yesterday's 12 UTC ensemble prediction (type: perturbed forecast) for the next 3 days at noon. > see in MARS Catalogue
retrieve,
class = od,
stream = ef,
type = perturbed forecast,
levtype = sfc,
repres = gg,
date = -1,
time = 12,
ensemble = 1/to/10,
step = 48/to/96/by/24,
param = |
Retrieve the same for the control forecast. > see in MARS Catalogue
retrieve, class = od, stream = ef, type = control forecast, levtype = sfc, repres = gg, date = -1, time = 12, step = 48/to/96/by/24, param = st, target = "ensemble.cf" |
Retrieve the vertical integral of eastward and northward heat flux as monthly means of daily means on a 1.125 by 1.125 degree latitude/longitude grid over Europe from the ERA 40 archive for January 1964 > see in MARS Catalogue
retrieve, class = e4, stream = moda, type = an, levtype = sfc, date = 19640101, param = 69.162/70.162, area = europe, grid = 1.125/1.125, target = "e4_moda_fluxes.grb" |
Retrieval of snow depth from the ERA-40 archive for November 1993, for all analysis base times > see in MARS Catalogue. How many fields are requested?
retrieve, class = e4, stream = oper, expver = 1, date = 19931101/to/19931130, time = 00/06/12/18, type = an, levtype = sfc, param = sd, repres = gg, target = "era40.199311.sd" # It retrieves 30 x 4 = 120 fields. |