CDO User's Guide Climate Data Operators Version 1.5.9 December 2012 Uwe Schulzweida, Luis Kornblueh { MPI for Meteorology Ralf Quast { Brockmann Consult Contents 1. Introduction 6 1.1. Building from sources.......................................6 1.1.1. Compilation.........................................7 1.1.2. Installation.........................................7 1.2. Usage................................................7 1.2.1. Options...........................................8 1.2.2. Operators..........................................8 1.2.3. Combining operators....................................9 1.2.4. Operator parameter....................................9 1.3. Horizontal grids...........................................9 1.3.1. Grid area weights...................................... 10 1.3.2. Grid description...................................... 10 1.4. Z-axis description.......................................... 13 1.5. Time axis.............................................. 14 1.5.1. Absolute time........................................ 14 1.5.2. Relative time........................................ 14 1.5.3. Conversion of the time................................... 14 1.6. Parameter table........................................... 14 1.7. Missing values............................................ 15 1.7.1. Mean and average..................................... 15 2. Reference manual 16 2.1. Information............................................. 17 2.1.1. INFO - Information and simple statistics........................ 18 2.1.2. SINFO - Short information................................ 19 2.1.3. DIFF - Compare two datasets field by field....................... 20 2.1.4. NINFO - Print the number of parameters, levels or times............... 21 2.1.5. SHOWINFO - Show variables, levels or times...................... 22 2.1.6. FILEDES - Dataset description.............................. 23 2.2. File operations........................................... 24 2.2.1. COPY - Copy datasets................................... 25 2.2.2. REPLACE - Replace variables.............................. 26 2.2.3. MERGE - Merge datasets................................. 27 2.2.4. SPLIT - Split a dataset.................................. 28 2.2.5. SPLITTIME - Split timesteps of a dataset........................ 30 2.2.6. SPLITSEL - Split selected timesteps........................... 31 2.3. Selection............................................... 32 2.3.1. SELVAR - Select fields................................... 33 2.3.2. SELTIME - Select timesteps............................... 36 2.3.3. SELBOX - Select a box of a field............................. 38 2.4. Conditional selection........................................ 39 2.4.1. COND - Conditional select one field........................... 40 2.4.2. COND2 - Conditional select two fields.......................... 40 2.4.3. CONDC - Conditional select a constant......................... 41 2.5. Comparison............................................. 42 2.5.1. COMP - Comparison of two fields............................ 43 2.5.2. COMPC - Comparison of a field with a constant.................... 44 2.6. Modification............................................. 45 2.6.1. SET - Set field info..................................... 47 2 Contents Contents 2.6.2. SETTIME - Set time.................................... 48 2.6.3. CHANGE - Change field header............................. 50 2.6.4. SETGRID - Set grid information............................. 52 2.6.5. SETZAXIS - Set z-axis type................................ 53 2.6.6. SETGATT - Set global attribute............................. 54 2.6.7. INVERT - Invert latitudes................................. 55 2.6.8. INVERTLEV - Invert levels................................ 55 2.6.9. MASKREGION - Mask regions.............................. 56 2.6.10. MASKBOX - Mask a box................................. 57 2.6.11. SETBOX - Set a box to constant............................. 58 2.6.12. ENLARGE - Enlarge fields................................ 59 2.6.13. SETMISS - Set missing value............................... 60 2.7. Arithmetic.............................................. 62 2.7.1. EXPR - Evaluate expressions............................... 64 2.7.2. MATH - Mathematical functions............................. 66 2.7.3. ARITHC - Arithmetic with a constant.......................... 67 2.7.4. ARITH - Arithmetic on two datasets........................... 68 2.7.5. MONARITH - Monthly arithmetic............................ 69 2.7.6. YMONARITH - Multi-year monthly arithmetic..................... 70 2.7.7. YDAYARITH - Multi-year daily arithmetic....................... 71 2.7.8. YHOURARITH - Multi-year hourly arithmetic..................... 72 2.7.9. ARITHDAYS - Arithmetic with days.......................... 73 2.8. Statistical values.......................................... 74 2.8.1. CONSECSTAT - Consecute timestep periods...................... 79 2.8.2. ENSSTAT - Statistical values over an ensemble..................... 80 2.8.3. ENSSTAT2 - Statistical values over an ensemble.................... 82 2.8.4. ENSVAL - Ensemble validation tools........................... 83 2.8.5. FLDSTAT - Statistical values over a field........................ 85 2.8.6. ZONSTAT - Zonal statistical values........................... 87 2.8.7. MERSTAT - Meridional statistical values........................ 89 2.8.8. GRIDBOXSTAT - Statistical values over grid boxes.................. 91 2.8.9. VERTSTAT - Vertical statistical values......................... 92 2.8.10. TIMSELSTAT - Time range statistical values...................... 93 2.8.11. TIMSELPCTL - Time range percentile values...................... 94 2.8.12. RUNSTAT - Running statistical values.......................... 95 2.8.13. RUNPCTL - Running percentile values......................... 96 2.8.14. TIMSTAT - Statistical values over all timesteps..................... 97 2.8.15. TIMPCTL - Percentile values over all timesteps.................... 98 2.8.16. HOURSTAT - Hourly statistical values......................... 99 2.8.17. HOURPCTL - Hourly percentile values......................... 100 2.8.18. DAYSTAT - Daily statistical values........................... 101 2.8.19. DAYPCTL - Daily percentile values........................... 102 2.8.20. MONSTAT - Monthly statistical values......................... 103 2.8.21. MONPCTL - Monthly percentile values......................... 104 2.8.22. YEARSTAT - Yearly statistical values.......................... 105 2.8.23. YEARPCTL - Yearly percentile values.......................... 106 2.8.24. SEASSTAT - Seasonal statistical values......................... 107 2.8.25. SEASPCTL - Seasonal percentile values......................... 108 2.8.26. YHOURSTAT - Multi-year hourly statistical values.................. 109 2.8.27. YDAYSTAT - Multi-year daily statistical values.................... 110 2.8.28. YDAYPCTL - Multi-year daily percentile values.................... 111 2.8.29. YMONSTAT - Multi-year monthly statistical values.................. 112 2.8.30. YMONPCTL - Multi-year monthly percentile values.................. 113 2.8.31. YSEASSTAT - Multi-year seasonal statistical values.................. 114 2.8.32. YSEASPCTL - Multi-year seasonal percentile values.................. 115 2.8.33. YDRUNSTAT - Multi-year daily running statistical values............... 116 2.8.34. YDRUNPCTL - Multi-year daily running percentile values.............. 118 3 Contents Contents 2.9. Correlation and co.......................................... 119 2.9.1. FLDCOR - Correlation in grid space........................... 120 2.9.2. TIMCOR - Correlation over time............................. 120 2.9.3. FLDCOVAR - Covariance in grid space......................... 121 2.9.4. TIMCOVAR - Covariance over time........................... 121 2.10. Regression.............................................. 122 2.10.1. REGRES - Regression................................... 123 2.10.2. DETREND - Detrend time series............................. 123 2.10.3. TREND - Trend of time series.............................. 124 2.10.4. SUBTREND - Subtract a trend.............................. 124 2.11. EOFs................................................ 125 2.11.1. EOFS - Empirical Orthogonal Functions......................... 126 2.11.2. EOFCOEFF - Principal coefficients of EOFs...................... 128 2.12. Interpolation............................................ 129 2.12.1. REMAPGRID - SCRIP grid interpolation........................ 130 2.12.2. GENWEIGHTS - Generate SCRIP grid interpolation weights............. 132 2.12.3. REMAP - SCRIP grid remapping............................ 134 2.12.4. REMAPETA - Remap vertical hybrid level....................... 135 2.12.5. INTVERT - Vertical interpolation............................ 137 2.12.6. INTLEVEL - Linear level interpolation......................... 138 2.12.7. INTLEVEL3D - Linear level interpolation from/to 3d vertical coordinates...... 139 2.12.8. INTTIME - Time interpolation.............................. 140 2.12.9. INTYEAR - Year interpolation.............................. 141 2.13. Transformation........................................... 142 2.13.1. SPECTRAL - Spectral transformation.......................... 143 2.13.2. WIND - Wind transformation............................... 145 2.14. Import/Export........................................... 146 2.14.1. IMPORTBINARY - Import binary data sets...................... 147 2.14.2. IMPORTCMSAF - Import CM-SAF HDF5 files.................... 148