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Analysis of long-term coastal tide records at Key West, Pensacola, and Mayport, Fla. examines the variability of extreme high-water events. Linear trends of event water level at Key West and Pensacola support findings elsewhere that increases in extreme water level are consistent with increases in global mean sea level. A link between event variables and the Atlantic multidecadal oscillation (AMO) is found at the Key West and Pensacola stations. Mayport does not exhibit such a link, likely the data are confounded by estuarine flows and oceanographic interactions with the St. Johns River. Quantile regressions and extreme value distributions suggest dynamic trends in the event variables at Key West and Pensacola as a function of AMO, indicating an increased variability in relation to linear models that should be of interest to coastal planners and forecasters. DOI: 10.1061/(ASCE)WW.1943-5460.0000052 CE Database subject headings: Coastal processes; Climates; Storm surges; Infrastructure; Sea level; Florida. Author keywords: Coastal processes; Climates; Surge; Infrastructure.

Because of its low topographic relief, unique hydrology, and the large interannual variability of precipitation, Florida is especially vulnerable to climate change. In this paper, we investigate a comprehensive collection of climate metrics to study historical trends in both averages and extremes of precipitation and temperature in the state. The data investigated consist of long-term records (1892-2008) of precipitation and raw (unadjusted) temperature at 32 stations distributed throughout the state. To evaluate trends in climate metrics, we use an iterative pre-whitening method, which aims to separate positive autocorrelation from trend present in time series. Results show a general decrease in wet season precipitation, most evident for the month of May and possibly tied to a delayed onset of the wet season. In contrast, there seems to be an increase in the number of wet days during the dry season, especially during November through January. We found that the number of dog days (above 26.7 °C) during the year and during the wet season has increased at many locations. For the post-1950 period, a widespread decrease in the daily temperature range (DTR) is observed mainly because of increased daily minimum temperature (Tmin). Although we did not attempt to formally attribute these trends to natural versus anthropogenic causes, we find that the urban heat island effect is at least partially responsible for the increase in Tmin and its corresponding decrease in DTR at urbanized stations compared with nearby rural stations. In the future, a formal trend attribution study should be conducted for the region. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]