User option for values in the output file. The valid values for each file are:

Optical Thickness - The latest Aerosol Optical Thickness calculated based on the previous analysis optical thickness, weighted according to its reliability, combined with a weighted average of current observations within a surrounding area which is determined according to the grid point's gradient.

Gradient in X- Direction - Change in optical thickness in the negative direction along the X axis.

Gradient in X+ Direction - Change in optical thickness between the grid point and neighbor points within the field in the positive direction along the X axis.

Gradient in Y- Direction - Change in optical thickness in the negative direction along the Y axis.

Gradient in Y+ Direction - Change in optical thickness in the positive direction along the Y axis.

Average Gradient - The average of the gradients in all four directions (N, S, E, W) from the grid intersection.

Climatological Temperature - The average sea surface temperature of a grid intersection for a particular month over a number of years, taken from the global climatology file.

Spatial Covariance X- - The distance in grid units from the grid intersection to the nearest land mass in the negative direction along the X axis.

Spatial Covariance X+ - The distance in grid units from the grid intersection to the nearest land mass in the positive direction along the X axis.

Spatial Covariance Y- - The distance in grid units from the grid intersection to the nearest land mass in the negative direction along the Y axis.

Spatial Covariance Y+ - The distance in grid units from the grid intersection to the nearest land mass in the positive direction along the Y axis.

Physiographic Descriptor - The land/sea tag indicating whether a grid intersection is a land or sea point.

Age of Most Recent Observation - The age, in hours from the time of last analysis, of the most recent observation used to determine the new optical thickness for a grid intersection.

Class 1 Temporal Coverage - Set of bits (0-15) of which bit 1 is set to 1 for each analysis which included observations with a reliability greater than or equal to a specific minimum reliability considered as class 1. Bit 0 always remains a 0, and all bits are shifted right during each analysis leaving bit 1 a 0 when no class 1 reliability observations are used for a grid intersection.

Number of Observations - The total number of current observations used in the analysis of the new optical thickness for the grid intersection.

Weight/ Reliability - New reliability associated with the new optical thickness, based on the previous reliability combined with the weighted reliability of all observations used in the last analysis.