Comparisons of POLDER-2 Rayleigh and Oxygen pressure with MODIS and ISCCP cloud top pressure
Comparisons of POLDER-2 Rayleigh and Oxygen pressure with MODIS and ISCCP cloud top pressure
Figure 1: Monthly mean of POLDER-2 Rayleigh pressure for June 2003
Figure 2: Monthly mean of POLDER-2 Oxygen pressure for June 2003
Figure 3: Monthly mean of MODIS cloud top pressure (day mean) for June 2003
Figure 4: Monthly mean of ISCCP cloud top pressure for June 1997
Figure 5: Monthly mean difference between POLDER-2 Rayleigh pressure and
MODIS cloud top pressure (day mean) for June 2003
Figure 6: Monthly mean difference between POLDER-2 Oxygen pressure and
MODIS cloud top pressure (day mean) for June 2003
The comparison between POLDER-2 Rayleigh pressure and MODIS cloud top pressure (fig. 5) exhibits high discrepancies: POLDER-2 Oxygen pressure is not a cloud top pressure retrieval but more a mean cloud pressure indicator (see comparisons with groundbased data). Comparison of this mean cloud pressure with MODIS cloud top pressure (fig. 6) is then quite surprising since the Oxygen pressure is often near and even lower than MODIS cloud top pressure (that's would mean a cloud middle upper than the cloud top). In addition to high discrepancies between POLDER-2 Rayleigh pressure and MODIS cloud top pressure, these comparisons seem to show that MODIS cloud top pressure are often too high (see fig. 7 for a summary) |
Figure 7: Scheme of the expected and the observed results for POLDER2
Rayleigh and Oxygen cloud pressure, MODIS and ISCCP cloud top pressure.
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