Tidal Marsh Water Level Data

All of these files are Microsoft Excel format files that contain water level data. We deployed 1-4 water level loggers and a single conductivity logger at all sites over the study period (Figure 6; Table 2). Primary water level loggers and conductivity loggers were deployed in major tidal channels connecting the marshes to the estuary. Secondary water level loggers were deployed in the upper reaches of second-order tidal channels to capture high tides and determine inundation patterns. Water level readings were collected every six minutes. We used data from the primary water level logger at each site to develop local hydrographs and inundation rates. Loggers were surveyed by RTK GPS at least once during the period of deployment. We corrected all raw water level data with local time series of barometric pressure using Solinst barometric loggers (Model 3001, Solinst Canada Ltd., Georgetown, Ontario, Canada), additional Hobo loggers (Model U-20-001-01-Ti, Onset Computer Corp., Bourne, MA, USA) or barometric pressure from local airports (distance less than 10 miles). We assessed salinity and water temperature in the tidal channels at each site with Odyssey conductivity/temperature loggers (Dataflow Systems Pty Limited, Christchurch, New Zealand), after an initial period of unsuccessful deployment of Hobo conductivity loggers (Model U-24-001, Onset Computer Corp., Bourne, MA, USA), that were recalled due to manufacture error and data inconsistencies. We converted specific conductance values obtained with the Odyssey loggers to practical salinity units (PSU) using the equation in UNESCO (1983). At Tijuana, we used salinity data from the National Estuarine Research Reserve System Centralized Data Management Office website, using the Boca Rio station (TJRBRWQ, 32.5595° N latitude, -117.1288° W longitude; cdmo.baruch.sc.edu). The water level data was used to estimate local tidal datums for all sites using procedures outlined in the NOAA Tidal Datums Handbook (NOAA 2003). Only local MHW and MHHW was calculated because the loggers were positioned in the intertidal and therefore could not be used to compute lower datums. Mean tide level (MTL) was estimated for each site by using NOAA’s VDATUM model (v.3.4) at the location of the primary water level logger or at a nearby site in the estuary if the VDATUM model domain did not include the water level logger location. At Bolinas we used NOAA published values for MTL, MHW and MHHW; the station was located about 2km from the study site.