The Science of Sustainability  Bay Area Tides    • share this
article   • Facebook   • Email  The Golden Gate transmits a vast
volume of water back and forth from the Bay twice each day,
regular as clockwork but in a much more complex rhythm. Photo by
Andrew Alden.  These days, most people in the San Francisco Bay
Area arrange their daily lives around the clock. But in former
times it was the sun, moon and tides that governed the rhythm of
our days. Nowadays the sun and moon attract notice only on the
rare occasions when they have eclipses. But the tides still
matter.  The twice-daily ebb and flow of the tides is not just a
factor for ships navigating the San Francisco Bay shallows,
although that is important. The tides are how the Bay breathes.
The Bay's windpipe is the Golden Gate, a deep channel that
enables seawater to spread nutrients and oxygenation to its
lungs—wetlands as far away as the Central Valley. In turn,
sediment from nearly half of California's surface area is
exhaled to the Pacific where it