Diagnosing Water Recycling/Water Exchange over Florida Peninsula with Coupled Mesoscale-SVATS Model

Water recycling and daily water exchange between the atmosphere and land surface is generally an important part of the maintenance of continental summertime convection, organized boundary layer circulations such as the sea breeze-land breeze couplet, and possibly the evolution of severe storms. Water recycling and water exchange are general terms, but in the context of the life cycle of water molecules during their presence within a regional domain, and for purposes of this study, water recycling pertains to the time scale over which precipitated water molecules return to the boundary layer to return it to its pre-existing moisture conditions, and water exchange signifies the difference between the daily rainfall accumulation and the daily integrated evapotranspiration (i.e., a negative value signifies water loss).

The water exchange variability and recycling time scales are relevant to various modes of behavior in the development of convection and storms, but generally not well understood or measured. The Florida peninsula is an excellent laboratory for studying water recycling/water exchange processes as has been discussed in the recent observational study of Cooper et al. (1998). The study presented here extends the original observational analysis through use of a high resolution, non-hydrostatic coupled mesoscale-SVATS model, and by running simulations designed to understand the significance of interactive feedbacks between the surface and boundary layer on water recycling time scales, water exchange and precipitation. The interactive model runs are interpreted with respect to a control experiment which only enables one-way forcing (surface to atmosphere).

Cooper, H.J., E.A. Smith, and M.T. Rubes, 1998: Relevance of surface energy budget within Florida sea breeze front to cross-peninsula rainwater runoff gradient. J. Appl. Meteor., 37, 39-50.