6b). Modeled station-specific FIB decay – driven only by advection and diffusion – was exponential for all alongshore stations ( SI Fig. 6), and exhibited a spatial pattern similar to HB06 FIB data, with significantly faster decay observed at northern stations than southern stations (Fig. 5a). Although the spatial patterns of decay estimated by the AD model matched those of HB06 FIB well, the actual magnitudes of the ON-01910 molecular weight decay rates were lower than observed (Fig. 5). The only station where the AD model captured FIB decay rates accurately (p < 0.05) was SAR, for E. coli (Fig. 5a). At all other stations, AD modeled FIB decay accounted for ⩽50% of observed decay (Fig. 5). This underestimation of FIB

decay rates suggests that an additional source of decay must be included in the model to accurately reproduce FIB dynamics during HB06. This additional decay is likely to be intrinsic to the FIB taxa, as the amount of unexplained FIB decay during HB06 was group-specific (Fig. 5). In the cross-shore, the AD model successfully reproduced FIB patterns for surfzone stations (F1, F3) and the offshore mooring (Enterococcus only), where FIB concentrations were consistently

near zero. It failed, however, to reproduce FIB patterns for offshore stations exhibiting FIB contamination (F5, F7) (Fig. 6b). www.selleckchem.com/products/17-AAG(Geldanamycin).html Poor model-data fits at these stations likely reflect over-retention of offshore FIB (Figs. 4 and 6a). Modeled FIB decay at these stations was significantly slower

than decay at F1 and F3, while observed FIB decay rates were constant across-shore (Fig. 5b). Together, the relatively poor model-data fits and decay-rate estimates for offshore stations suggest that, although the AD model performs well in the surfzone, it is missing a dominant process structuring offshore FIB concentrations during HB06. Through a synthesis of field observations and models, we have shown that a model including only horizontal advection and diffusion can explain a significant portion of the variability in FIB concentrations at Huntington Beach, Nintedanib (BIBF 1120) especially in the alongshore (Skill of 0.45–0.90 at alongshore stations and −0.23 to 0.74 at cross-shore stations, Fig. 6b). To our knowledge, HB06 is the first study to perform high-resolution monitoring of FIB, waves, and currents both in the surfzone and offshore, providing an opportunity to directly quantify the importance of these physical processes in structuring nearshore FIB pollution. The strong role of advection and diffusion in structuring patterns of FIB during HB06 was somewhat surprising given the temporal decays observed at each sampling station often attributed to solar insolation (e.g., Ki et al., 2007). Our analyses suggest, however, that a significant portion of this decay (mean of 38% for E. coli, and 14% for Enterococcus) was due to southward advection and diffusion of FIB patches through the study area (Fig. 5).