GMIS - MODIS-AQUA Monthly mean sea surface diffuse attenuation coefficient at 490nm (4km) in m^-1

Water Transparency (Diffuse attenuation coefficient at 490nm, Kd490 in m^-1 at 4km resolution): The diffuse attenuation coefficient Kd490 measures the light penetration in the water column at the blue-green wavelengths (ca. 490 nm). It represents a good indicator of water transparency resulting from the combined action of absorption and backscattering by the water constituents, and the structure of the surrounding light field.水体透明度数据集的核心参数为490nm处漫衰减系数（Diffuse attenuation coefficient at 490nm，记为Kd490），该参数单位为m⁻¹，空间分辨率为4km：490nm处漫衰减系数Kd490用于表征蓝绿波段（约490nm）下水体柱中的光穿透能力。该系数可作为水体透明度的优良指示因子，其大小由水体各组分的吸收、后向散射作用以及周围光场的结构共同决定。