Variation of population density on a beach: A simple analytical formulation

Since the novel coronavirus was reported (December 2019), the virus spread rapidly breaking through frontiers and impacting almost all countries of the world. Tourism is one of the sectors that has been heavily affected by the crisis. Even though there are several protocols for tourism activities that were written for the austral summer season, at the present, physical distancing is considered an effective way to reduce the spread of the virus. Clear and simple public actions should be rapidly implemented by the authorities to minimize the number of people on the beach. For instance, increasing the number of accesses to the beaches, building parking lots adjacent to the farthest beaches, or opening coastal roads on the outskirts of town to expand usable beaches, would be some simple and direct measures to reduce the beach population density. A simple analytical formulation for assessing the percentage decrease of the static population density respect to the absolute maximum population density on a beach is described in this paper. The variables of this simple analytical tool are the instantaneous sea-level (tide), air temperature, and beach expansion. Beach expansion is the single and manageable variable of the formulation, and refers to the inclusion of some near or adjacent extension of beach. It is suggested that the expansion of beaches would be very useful not only for pandemic time but also for the new normality. An application of this methodology is presented in the municipality of La Costa, Argentina.