ON FLUCTUATIONS OF THE ATMOSPHERIC CIRCULATION IN THE VICINITY OF SOUTH AMERICA, AND THEIR RELATION TO SUNSPOTS

Abstract

The longitudinal section of pressure distribution over a given hemisphere shows minima near the equator and at about latitude 60 deg, and has maxima at about latitude 30 deg and near the pole. A trigonometric equation with a minimum of parameters to represent these conditions has been assumed: p = p? + R sin (K? + E) in the range 0 < ? < 2π/K. The adequacy of this equation to represent the actual long-term variations of pressure on a section near South America was studied in an earlier contribution (1949), that involved application of this equation to mean April?May pressures. The correlation coefficients for every pair of variations of the parameters, and between the parameters and sunspot numbers have now been determined. The former indicate that changes of the atmospheric circulation consist of fluctuations between low- and high-index circulations. The fluctuations also seem to be related to sunspots and changes in sunspots.