Oceanographic variability in the inner shelf of parana, Brazil: Spring condition

Abstract

The hydrographic and hydrodynamics data obtained from a 10 meters deep mooring (0.5 meter above the bottom) located in the Inner Shelf of Paraná, Brazil, from Oct/11/2006 to Dec/10/2006, were analyzed. The oceanographic variability was characterized by maximum values of 54.2 cm.s-1for current, 2.9 m for height, and 10 s for wave period. The salinity ranged from 32 to 33.7 ups and temperature from 20.7 to 25.3˚C. The wind stress is the main force driving the oceanographic variability, especially during high-energy events, generating waves bigger than 2.5 m, which occur with periods of 7.6 days. The low frequency oscillations dominate the behavior of longshore currents. These currents also answer more effectively to the wind variability. Themost important tidal components were the lunar and solar semi-diurnal, M2and S2, respectively. The temperature and salinity response to the wind effect is faster than circulation pattern response. However, the variability of temperature and salinity associated with the wind energy peaks still needs to be better understood. For this, we need a better understanding of the sources of heat and salt, both local and remote, as well as their variability.