The Color of the Bay: Green Waters and Anthropogenic Influences

The bay's water color has shifted over time from blue to green as observed by residents like Justin Hartung, with particular changes noted near Emeryville. Jim Cloran, a biologist with extensive experience studying the bay, explains that water color is influenced by light absorption, with non-living clay particles and microscopic algae (phytoplankton) contributing to the green hue through various sources like erosion and runoff. Data collected since 1968 shows an increasing trend of phytoplankton abundance, leading to greener bay waters, partly attributed to reduced sediment input and shifts in the biological communities.