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11The work done on the intertidal landscape by low tide rainfall events has been shown 12 to augment the cycling of dissolved and particulate nutrients, but low tide rainfall events 13 are not a well-documented component of coastal ecosystem models. Here we develop the 14 relationships between rainfall intensity (I), and median volume raindrop diameter, and 15 three rainfall erosivity indices (kinetic energy, momentum, and momentum multiplied by 16 the drop diameter) using an optical disdrometer deployed in the intertidal zone during 17 summer and fall of 2010 and 2011. These data include the local effects of Hurricane Irene 18 in 2011. Raindrop data measured for 27 days of late summer were analyzed. The best fit 19 between median volume raindrop diameter and I was a combination of the power-law and 20 logarithm equations, and the best fits of three erosivity indices and I were obtained with 21 power-law equations. Kinetic energy was slightly higher than the world average. 22Observed raindrop velocity was typically lower and more widely distributed than the 23 theoretical raindrop terminal velocity. Hence, erosivity indices based on observed 24 velocity were lower than those based on terminal velocity. The hurricane provided larger 25 raindrops and more widely distributed raindrop velocity than normal events. Overall, 26 results indicate that it is not suitable to assume that background erosivity-I relationships 27 apply to cyclonic events. We derived new erosivity-I relationships to help characterize 28 soil erosion processes in salt marsh areas for normal events. These results will help 29 predict material and nutrient fluxes between intertidal and subtidal landscapes. 30 31

Influences of tides, freshwater discharge, and winds on water properties in the St. Jones River estuary (USA), a Delaware National Estuarine Research Reserve, were investigated using multiyear records of sea level, salinity, and turbidity, supplemented by a current profiler time series in 2007. Results demonstrate that instantaneous properties fluctuate with semidiurnal tides and resonant overtides, whereas tidal mean variations are forced by seasonal freshwater inflow and offshore winds. Mean sea level and salinity are highest in summer and vary with seasonal water temperature and rainfall, whereas sea level variability and turbidity are highest in winter on account of storm effects. Salinity and discharge modeling suggest that much (43-65%) of the freshwater resident in the estuary is derived from non-point sources below the head of tide. This diffuse freshwater inflow produces a seaward surface slope and weak mean current, which temporarily reverses under the influence of storm-wind setup within Delaware Bay.

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