This poster was presented at the August 2009 meeting of the:
American Association for the Advancement of Science, Pacific Division.

Water temperature versus time profiles for characterization of wetlands and shallow esturaries

Michael Konrad (Science Is Art, Sausalito CA 94965;








On sunny days water in tidal wetlands and shallow estuaries can become warmer and on cold nights cooler than the deeper water that feeds them. When the tide ebbs, water flowing from the entrance to these shallow areas back into deep water carries a temperature signature which characterizes the relative area and depth of the shallow water. During daytime, heating in shallow areas is superimposed on the heating of all surface water, which causes distortions to the typical daily warming curve of the surface of the deeper water. However, at night, warm shallow areas can generate anomalous temperature peaks as water from that region ebbs past the entrance to the estuary. During cold nights cooling of shallow water can cause corresponding dips in the temperature-time profile. If fresh water streams empty into the shallow regions water temperature is modified by the temperature of the stream. In addition, the low salinity stream water can float over the higher salinity water from the entrance to the estuary, suppressing mixing and thus preserving the unique temperature of the shallow waters. Temperature-time profiles in San Francisco Bay and Richardson Bay, a shallow extension of the San Francisco Bay system, will be presented to illustrate these principles. The use of inexpensive temperature loggers, designed to monitor goods during transport, made this work possible.









North San Francisco Bay
Richardson Bay