The SeaWiFS monthly climatology data used in the Ocean-Giovanni system are products of
the Ocean Biology Processing Group (OBPG), downloaded from the
ocean color ftp site.
The current climatology data are derived by time-binning the monthly binned
files from September 1997 through August 2007, and mapping to an Equidistant Cylindrical projection,
with 9km resolution at
the equator, similar to monthly Standard Mapped Image (SMI) products. For example,
the January Climatology data are
time-binned for each January from 1998 to 2007. Weighting of 1/sqrt(n) is applied for
time-binning, where n is the number of valid pixels within a binning area. The same time
binning software used for generating 8-day or monthly products is applied to climatologies
( SeaWiFS Prelaunch TM 32, appendix B).
For these climatologies, each month is derived from 9 years of
monthly bins.
The SeaWiFS monthly anomaly data is simply the difference of the monthly SMI data product,
such as chlorophyll a, and the monthly climatology SMI for that product.
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