4.20 - Penman-Monteith Crop Coefficient File (*.kpm)
The crop coefficient file (*.kpm) contains Penman-Monteith crop coefficient curves, as defined in ASCE-70.
The same crop coefficient curves are used for the Penman-Monteith and the ASCE Standardized Penman-Monteith
methods. This file is read when flag1= 3 or 5 in the model control file (see Section 4.4). The
recommended naming convention to identify crops with their crop coefficients is Crop_Name.XXX as described
in Section 3.1.7. An example is provided in Appendix A.
| Row-Data | Program Variable | Description |
|---|---|---|
| Row 1 | Format (a80) | |
| 1-1 | remark | Title |
| Row 2 | Free Format | |
| 2-1 | nc | Number of crop coefficient curves |
| 3-1 | id | Crop number (not used in StateCU) |
| 3-2 | cropn | Crop name |
| 4-1 | kcday(1,j) | Time from start of growth to effective cover (%) or number of days after effective cover |
| 4-2 | kcb(1,j) | Corresponding crop coefficient for alfalfa-based ET, for crop j |
Read 33 day/crop coefficient pairs (Row 4) for alfalfa
Read 11 day/crop coefficient pairs (Row 4) for grass pasture
Read 22 day/crop coefficient pairs (Row 4) for all other crop types
Repeat for the number of crop coefficient curves, nc