CDO User Guide - code.mpimet.mpg.de

1 CDO user Guide Climate Data Operator Version October 2019. Uwe Schulzweida MPI for Meteorology Contents 1. Introduction 6. Building from sources .. 6. Compilation .. 7. Installation .. 7. Usage .. 7. Options .. 8. Environment variables .. 9. Operators .. 9. Operator chaining .. 9. Parallelized operators .. 10. Operator parameter .. 10. Horizontal grids .. 11. Grid area weights .. 11. Grid description .. 11. Z-axis description .. 15. Time axis .. 16. Absolute time .. 16. Relative time .. 16. Conversion of the time .. 16. Parameter table .. 16. Missing values .. 16. Mean and average .. 17. Percentile .. 17. Percentile over timesteps .. 18. 2. Reference manual 19. Information .. 20. INFO - Information and simple statistics .. 21. SINFO - Short information .. 22. DIFF - Compare two datasets field by field.

2 23. NINFO - Print the number of parameters, levels or times .. 24. SHOWINFO - Show variables, levels or times .. 25. SHOWATTRIBUTE - Show attributes .. 26. FILEDES - Dataset description .. 27. File operations .. 28. APPLY - Apply an operator .. 29. COPY - Copy datasets .. 30. TEE - Duplicate a data stream and write it to file .. 31. REPLACE - Replace variables .. 32. DUPLICATE - Duplicates a dataset .. 32. MERGEGRID - Merge grid .. 32. MERGE - Merge datasets .. 33. SPLIT - Split a dataset .. 34. SPLITTIME - Split timesteps of a dataset .. 36. SPLITSEL - Split selected timesteps .. 37. DISTGRID - Distribute horizontal grid .. 38. COLLGRID - Collect horizontal grid .. 39. Selection .. 40. SELECT - Select fields .. 41. SELMULTI - Select multiple fields via GRIB1 parameters .. 43. 2. Contents Contents SELVAR - Select fields.

3 44. SELTIME - Select timesteps .. 46. SELBOX - Select a box of a field .. 48. SELGRIDCELL - Select grid cells .. 49. SAMPLEGRID - Resample grid .. 49. SELYEARIDX - Select year by index .. 49. Conditional selection .. 50. COND - Conditional select one field .. 51. COND2 - Conditional select two fields .. 51. CONDC - Conditional select a constant .. 52. MAPREDUCE - Reduce fields to user -defined mask .. 53. Comparison .. 54. COMP - Comparison of two fields .. 55. COMPC - Comparison of a field with a constant .. 56. Modification .. 57. SETATTRIBUTE - Set attributes .. 59. SETPARTAB - Set parameter table .. 60. SET - Set field info .. 62. SETTIME - Set time .. 63. CHANGE - Change field header .. 65. SETGRID - Set grid information .. 66. SETZAXIS - Set z-axis information .. 67. INVERT - Invert latitudes.

4 68. INVERTLEV - Invert levels .. 68. SHIFTXY - Shift field .. 69. MASKREGION - Mask regions .. 70. MASKBOX - Mask a box .. 71. SETBOX - Set a box to constant .. 72. ENLARGE - Enlarge fields .. 73. SETMISS - Set missing value .. 74. Arithmetic .. 76. EXPR - Evaluate expressions .. 78. MATH - Mathematical functions .. 81. ARITHC - Arithmetic with a constant .. 83. ARITH - Arithmetic on two datasets .. 84. MONARITH - Monthly arithmetic .. 85. YHOURARITH - Multi-year hourly arithmetic .. 86. YDAYARITH - Multi-year daily arithmetic .. 87. YMONARITH - Multi-year monthly arithmetic .. 88. YSEASARITH - Multi-year seasonal arithmetic .. 89. ARITHDAYS - Arithmetic with days .. 89. Statistical values .. 90. TIMCUMSUM - Cumulative sum over all timesteps .. 97. CONSECSTAT - Consecute timestep periods .. 97. VARSSTAT - Statistical values over all variables.

5 98. ENSSTAT - Statistical values over an ensemble .. 99. ENSSTAT2 - Statistical values over an ensemble .. 101. ENSVAL - Ensemble validation tools .. 102. FLDSTAT - Statistical values over a field .. 104. ZONSTAT - Zonal statistical values .. 106. MERSTAT - Meridional statistical values .. 107. GRIDBOXSTAT - Statistical values over grid boxes .. 109. VERTSTAT - Vertical statistical values .. 110. TIMSELSTAT - Time range statistical values .. 111. TIMSELPCTL - Time range percentile values .. 112. RUNSTAT - Running statistical values .. 113. RUNPCTL - Running percentile values .. 114. TIMSTAT - Statistical values over all timesteps .. 115. 3. Contents Contents TIMPCTL - Percentile values over all timesteps .. 116. HOURSTAT - Hourly statistical values .. 117. HOURPCTL - Hourly percentile values .. 118.

6 DAYSTAT - Daily statistical values .. 119. DAYPCTL - Daily percentile values .. 120. MONSTAT - Monthly statistical values .. 121. MONPCTL - Monthly percentile values .. 122. YEARMONSTAT - Yearly mean from monthly data .. 123. YEARSTAT - Yearly statistical values .. 124. YEARPCTL - Yearly percentile values .. 125. SEASSTAT - Seasonal statistical values .. 126. SEASPCTL - Seasonal percentile values .. 127. YHOURSTAT - Multi-year hourly statistical values .. 128. DHOURSTAT - Multi-day hourly statistical values .. 130. YDAYSTAT - Multi-year daily statistical values .. 132. YDAYPCTL - Multi-year daily percentile values .. 134. YMONSTAT - Multi-year monthly statistical values .. 135. YMONPCTL - Multi-year monthly percentile values .. 137. YSEASSTAT - Multi-year seasonal statistical values .. 138. YSEASPCTL - Multi-year seasonal percentile values.

7 140. YDRUNSTAT - Multi-year daily running statistical values .. 141. YDRUNPCTL - Multi-year daily running percentile values .. 143. Correlation and co.. 144. FLDCOR - Correlation in grid space .. 145. TIMCOR - Correlation over time .. 145. FLDCOVAR - Covariance in grid space .. 146. TIMCOVAR - Covariance over time .. 146. Regression .. 147. REGRES - Regression .. 148. DETREND - Detrend time series .. 148. TREND - Trend of time series .. 150. SUBTREND - Subtract a trend .. 150. EOFs .. 151. EOFS - Empirical Orthogonal Functions .. 152. EOFCOEFF - Principal coefficients of EOFs .. 154. Interpolation .. 155. REMAPBIL - Bilinear interpolation .. 156. REMAPBIC - Bicubic interpolation .. 157. REMAPNN - Nearest neighbor remapping .. 158. REMAPDIS - Distance-weighted average remapping .. 159. REMAPCON - First order conservative remapping.

8 160. REMAPCON2 - Second order conservative remapping .. 162. REMAPLAF - Largest area fraction remapping .. 164. REMAP - Grid remapping .. 165. REMAPETA - Remap vertical hybrid level .. 166. - Vertical interpolation .. 168. - Vertical interpolation .. 168. - Linear level interpolation .. 169. - Linear level interpolation from/to 3d vertical coordinates .. 171. - Time interpolation .. 172. - Year interpolation .. 173. Transformation .. 174. SPECTRAL - Spectral transformation .. 175. SPECCONV - Spectral conversion .. 176. WIND2 - D and V to velocity potential and stream function .. 176. WIND - Wind transformation .. 177. FOURIER - Fourier transformation .. 178. 4. Contents Contents Import/Export .. 179. IMPORTBINARY - Import binary data sets .. 180. IMPORTCMSAF - Import CM-SAF HDF5 files .. 181. IMPORTAMSR - Import AMSR binary files.

9 182. INPUT - Formatted input .. 183. OUTPUT - Formatted output .. 184. OUTPUTTAB - Table output .. 185. OUTPUTGMT - GMT output .. 186. Miscellaneous .. 188. GRADSDES - GrADS data descriptor file .. 190. AFTERBURNER - ECHAM standard post processor .. 191. FILTER - Time series filtering .. 193. GRIDCELL - Grid cell quantities .. 194. SMOOTH - Smooth grid points .. 195. DELTAT - Difference between timesteps .. 195. REPLACEVALUES - Replace variable values .. 196. VARGEN - Generate a field .. 197. TIMSORT - Timsort .. 198. - Wind Transformation .. 199. - Rotation .. 200. - Mass stream function .. 200. - Sea level pressure .. 200. - Potential temperature to in-situ temperature and vice versa .. 201. - Calculates potential density .. 201. - Histogram .. 202. - Set the left and right bounds of a field .. 202.

10 - Windchill temperature .. 203. - Frost days where no snow index per time period .. 203. - Strong wind days index per time period .. 203. - Strong breeze days index per time period .. 204. - Strong gale days index per time period .. 204. - Hurricane days index per time period .. 204. - CMOR lite .. 205. 3. Contributors 207. History .. 207. External sources .. 207. Contributors .. 207. A. Environment Variables 211. B. Parallelized operators 212. C. Standard name table 214. D. Grid description examples 215. Example of a curvilinear grid description .. 215. Example description for an unstructured grid .. 216. Operator index 217. 5. 1. Introduction The Climate Data Operator (CDO) software is a collection of many operators for standard processing of climate and forecast model data. The operators include simple statistical and arithmetic functions, data selection and subsampling tools, and spatial interpolation.