Affiliation:
1. Instituto de Física Universidade de Brasília Brasília Brazil
2. Faculdade do Gama Universidade de Brasília Brasília Brazil
Abstract
The mean annual components of the solar and lunar atmospheric tides over Brazil were obtained from the analysis of surface pressure data from 369 modern weather stations. The spatial coverage area and density of the data presented provide a high level of detail that has not been presented before. For the solar atmospheric tide, it was found that the amplitudes of the diurnal and semidiurnal components are comparable, each ranging from 0.2–1.7 mbar. The diurnal amplitude is irregularly distributed and influenced by the contour of the continent, its terrain, and climate. In contrast, the semidiurnal amplitude is more regularly distributed, measuring about 1.4 mbar at the Equator and decreasing towards higher latitudes. The amplitude of the lunar tide is normally distributed over the country, with a mean value of 0.08 mbar. The parameters obtained are spatially coherent, present little noise, and are both comprehensive and accurate. In addition, some statistical guidance on how to detect atmospheric tides properly at different latitudes is provided.