|
FORMAT: xxyyz (range: 00001 - 27279) xx = layer 1 ID (0 - 27) yy = layer 2 ID (0 - 27) z = surface type (1 - 9): 1 = water; 2 = forest; 3 = savannas; 4 = grasslands/croplands; 5 = open shrubs; 6 = barren desert; 7 = permanent snow; 8 = fresh snow; 9 = sea ice. |
| Cloud Layer ID: clear-sky FOV: xx = 0; yy = 0 cloudy single layer: xx = 1 - 27; yy = 0 cloudy multilayer: xx = 1 - 27; yy = 1 - 27 |
| NOTE: Layer 2 is only defined if the separation between two SSF layers crosses pressure boundaries. Otherwise, merge the two SSF layers into a single layer. |
| If FOV is cloudy, xx and/or yy are defined by cloud fraction, cloud height and cloud optical depth as follows: |
| PCL | MCL | OVC | |||||||
| HIGH | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 |
| MIDDLE | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 |
| LOW | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
| Thin | Mod | Thick | Thin | Mod | Thick | Thin | Mod | Thick | |
| Where |
| PCL: cld. fraction = 0.1 - 40% MCL: cld. fraction = 40 - 99% OVC: cld. fraction = 99 - 100% |
HIFH: eff. pressure < 440 mb MIDDLE: eff. pressure = 440 - 680 mb LOW: eff. pressure > 680 mb |
THIN: tau < 3.35 MOD: tau = 3.35 - 22.63 THICK: tau > 22.63 |
|
NOTES: - The EFFECTIVE CLOUD PRESSURE is used, not the CLOUD TOP PRESSURE. - To decode cloud classification index (icldtype): icld1 = int(icldtype/1000) icld2 = int(icldtype - icld1*1000)/10 isfctype = icldtype - icld1*1000 - icld2*10 - To determine cloud property array indices: ipres = int(icldx/9.001) + 1 icldf = int[ (icldx - (ipres - 1)*9)/3.001] + 1 itau = int[ (icldx - (ipres - 1)*9 - (icldf - 1)*3)/1.001] + 1 - From this SSF classification, one could map all possible layer, cloud fraction and tau combinations into a single digit. There are a total of 271 possible cloud conditions per surface type: 1 clear 27 single layer 81 multilayer: low + mid 81 multilayer: low + high 81 multilayer: mid + high |
| HOME | Overview | ADMs | Validation Results | Publications | Conferences | Production Code | Relevant Links |