Summary of bit processing for 1.25-km cloud mask:
| cmsk value | bit 7 | bit 6 | bit 5 | bit 4 | bit 3 | bit 2 | bit 1 | bit 0 |
|---|---|---|---|---|---|---|---|---|
| 200 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 0 |
| 255 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
bit 7: 0 = clear, 1 = cloudy
bit 6: 0 = not ice, 1 = ice (as derived from AVHRR)
bit 5: 0 = not ice, 1 = ice (as derived from SSM/I)
bit 4: 0 = not coastline, 1 = coastline
bit 3: 0 = water, 1 = land
bits 0,1,2: values of 0 to 7 (designating a cloud masking region)
For example, a data value of 200 specifies cloudy, ice as derived from AVHRR, not ice as derived from SSM/I, not coastline, land, and cloud masking region 0. A value of 255 indicates missing data.
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