Useful Tools
CDO
Possible example uses of CDO are:
Select a time from a file
To extract a single (or multiple) year from a multi-step file, you can use selyear,year:
$ cdo sinfon pchem.species.CMIP-5.1870-2097.z_91x72.nc4
File format: netCDF4
-1 : Institut Source Ttype Levels Num Gridsize Num Dtype : Parameter name
1 : unknown http://geos5.org/wiki/index.php?title=GEOS-5_Configuration_for_AR5 instant 72 1 91 1 F32 : OX
2 : unknown http://geos5.org/wiki/index.php?title=GEOS-5_Configuration_for_AR5 instant 72 1 91 1 F32 : N2O
3 : unknown http://geos5.org/wiki/index.php?title=GEOS-5_Configuration_for_AR5 instant 72 1 91 1 F32 : CFC11
4 : unknown http://geos5.org/wiki/index.php?title=GEOS-5_Configuration_for_AR5 instant 72 1 91 1 F32 : CFC12
5 : unknown http://geos5.org/wiki/index.php?title=GEOS-5_Configuration_for_AR5 instant 72 1 91 1 F32 : CH4
6 : unknown http://geos5.org/wiki/index.php?title=GEOS-5_Configuration_for_AR5 instant 72 1 91 1 F32 : HCFC22
7 : unknown http://geos5.org/wiki/index.php?title=GEOS-5_Configuration_for_AR5 instant 72 1 91 1 F32 : H2O
Grid coordinates :
1 : lonlat > size : dim = 91 nx = 0 ny = 91
lat : first = -1.57079637 last = 1.57079625 inc = 0.0349065065 radians
Vertical coordinates :
1 : generic layer : 1.5 2.63499999 4.01500034 5.67999983 7.76499939
10.4499998 13.960001 18.5400009 24.4899979 32.1749992
42.0400009 54.6300011 70.5950012 90.7249985 115.995003
147.565002 186.790009 235.26001 294.829987 367.649994
456.169983 563.179993 691.830017 845.63501 1028.49011
1246.01501 1505.02502 1812.43494 2176.09985 2604.90991
3108.89014 3699.26978 4390.96533 5201.58984 6149.56494
7255.78467 8543.89941 10051.4355 11825 13911.501
16366.1504 19254.0977 22651.3496 26647.9004 31279.1504
35625 39375 43125 46875 50625 54375 58125 61875
65625 69375 73125.0156 76250 78750 81250.0156 83750.0156
85750.0156 87250.0078 88750 90249.9844 91749.9844
93250.0078 94750 96249.9766 97374.9766 98124.9922
98875 99625
Time coordinate : 2736 steps
RefTime = 1870-01-15 12:00:00 Units = hours Calendar = standard
YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss
1870-01-15 12:00:00 1870-02-14 22:00:00 1870-03-17 08:00:00 1870-04-16 18:00:00
1870-05-17 04:00:00 1870-06-16 14:00:00 1870-07-17 00:00:00 1870-08-16 10:00:00
1870-09-15 20:00:00 1870-10-16 06:00:00 1870-11-15 16:00:00 1870-12-16 02:00:00
1871-01-15 12:00:00 1871-02-14 22:00:00 1871-03-17 08:00:00 1871-04-16 18:00:00
...snip...
2096-07-21 20:00:00 2096-08-21 06:00:00 2096-09-20 16:00:00 2096-10-21 02:00:00
2096-11-20 12:00:00 2096-12-20 22:00:00 2097-01-20 08:00:00 2097-02-19 18:00:00
2097-03-22 04:00:00 2097-04-21 14:00:00 2097-05-22 00:00:00 2097-06-21 10:00:00
2097-07-21 20:00:00 2097-08-21 06:00:00 2097-09-20 16:00:00 2097-10-21 02:00:00
cdo sinfon: Processed 7 variables over 2736 timesteps ( 0.11s )
$ cdo selyear,1999,2000,2001 pchem.species.CMIP-5.1870-2097.z_91x72.nc4 ~/test.nc4
cdo selyear: Processed 1651104 values from 7 variables over 2736 timesteps ( 0.73s )
$ cdo sinfon ~/test.nc4
File format: netCDF4
-1 : Institut Source Ttype Levels Num Gridsize Num Dtype : Parameter name
1 : unknown http://geos5.org/wiki/index.php?title=GEOS-5_Configuration_for_AR5 instant 72 1 91 1 F32 : OX
2 : unknown http://geos5.org/wiki/index.php?title=GEOS-5_Configuration_for_AR5 instant 72 1 91 1 F32 : N2O
3 : unknown http://geos5.org/wiki/index.php?title=GEOS-5_Configuration_for_AR5 instant 72 1 91 1 F32 : CFC11
4 : unknown http://geos5.org/wiki/index.php?title=GEOS-5_Configuration_for_AR5 instant 72 1 91 1 F32 : CFC12
5 : unknown http://geos5.org/wiki/index.php?title=GEOS-5_Configuration_for_AR5 instant 72 1 91 1 F32 : CH4
6 : unknown http://geos5.org/wiki/index.php?title=GEOS-5_Configuration_for_AR5 instant 72 1 91 1 F32 : HCFC22
7 : unknown http://geos5.org/wiki/index.php?title=GEOS-5_Configuration_for_AR5 instant 72 1 91 1 F32 : H2O
Grid coordinates :
1 : lonlat > size : dim = 91 nx = 0 ny = 91
lat : first = -1.57079637 last = 1.57079625 inc = 0.0349065065 radians
Vertical coordinates :
1 : generic layer : 1.5 2.63499999 4.01500034 5.67999983 7.76499939
10.4499998 13.960001 18.5400009 24.4899979 32.1749992
42.0400009 54.6300011 70.5950012 90.7249985 115.995003
147.565002 186.790009 235.26001 294.829987 367.649994
456.169983 563.179993 691.830017 845.63501 1028.49011
1246.01501 1505.02502 1812.43494 2176.09985 2604.90991
3108.89014 3699.26978 4390.96533 5201.58984 6149.56494
7255.78467 8543.89941 10051.4355 11825 13911.501
16366.1504 19254.0977 22651.3496 26647.9004 31279.1504
35625 39375 43125 46875 50625 54375 58125 61875
65625 69375 73125.0156 76250 78750 81250.0156 83750.0156
85750.0156 87250.0078 88750 90249.9844 91749.9844
93250.0078 94750 96249.9766 97374.9766 98124.9922
98875 99625
Time coordinate : 36 steps
RefTime = 1870-01-15 12:00:00 Units = hours Calendar = standard
YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss YYYY-MM-DD hh:mm:ss
1999-01-14 22:00:00 1999-02-14 08:00:00 1999-03-16 18:00:00 1999-04-16 04:00:00
1999-05-16 14:00:00 1999-06-16 00:00:00 1999-07-16 10:00:00 1999-08-15 20:00:00
1999-09-15 06:00:00 1999-10-15 16:00:00 1999-11-15 02:00:00 1999-12-15 12:00:00
2000-01-14 22:00:00 2000-02-14 08:00:00 2000-03-15 18:00:00 2000-04-15 04:00:00
2000-05-15 14:00:00 2000-06-15 00:00:00 2000-07-15 10:00:00 2000-08-14 20:00:00
2000-09-14 06:00:00 2000-10-14 16:00:00 2000-11-14 02:00:00 2000-12-14 12:00:00
2001-01-13 22:00:00 2001-02-13 08:00:00 2001-03-15 18:00:00 2001-04-15 04:00:00
2001-05-15 14:00:00 2001-06-15 00:00:00 2001-07-15 10:00:00 2001-08-14 20:00:00
2001-09-14 06:00:00 2001-10-14 16:00:00 2001-11-14 02:00:00 2001-12-14 12:00:00
cdo sinfon: Processed 7 variables over 36 timesteps ( 0.00s )