Seasonality/ storm events 

The Hawaiian Islands, like other tropical environments, are subject to distinct seasonal changes in the amount of rainfall received.  O‘ahu experiences rainfall throughout the year, but has an annual wet season (fall-winter) and dry season (spring-summer).  Coastal water quality in Hawai‘i has been linked to fluvial inputs and rain events (Cox et al. 2006; Decarlo et al. 2007; Hoover 2002; Ringuet and Mackenzie 2005).  Storms in Hawai‘i, as in other tropical ecosystems, occur as short-lived events and can account for up to 80% of the total annual load of sediments and nutrients delivered to the coastal ocean (Eyre 1995).  Coastal water quality is linked to fluvial inputs and rain events (De Carlo et al. 2007; Hoover and Mackenzie 2009; Ringuet and Mackenzie 2005). Rivers typically have higher concentrations of nutrients and suspended particulate matter than receiving waters, and introduce land-derived runoff to the coastal ocean (Bostater and Biggs 1985; Cox et al. 2006; Eyre and Balls 1999; Hoover and Mackenzie 2009; Ringuet and Mackenzie 2005; Wetz 2006; Wollheim et al. 2006). The impact of first flush storms, the first large storm of the rainy season, can have a particularly large impact on pond biogeochemistry and the ecosystem.


First flush storm:  beginning of the rainy season (November 2007)

The first flush storm event (storm threshold defined as ≥ 5.1 cm of rainfall within a twenty-four hour period over the watershed:  Ringuet and Mackenzie 2005; Fagan and Mackenzie 2007; Ostrander et al. 2008) during the initial year of HCOOS occurred on 11/04/07; pond sampling was executed on Nov. 4, 5, 6, 7, 8, and 11.  Not surprisingly, the storm had an enormous impact on the biogeochemistry of the fishpond, including a shift in limiting nutrient status and phytoplankton community composition.  Details of this study can be found in Timmerman et al. 2014; Young 2011; Hull 2010.  Include figure?


Tropical storm Wallie (July 2014)

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