A search for a solar cycle-tropical stratosphere temperature relationship

NIEVES ORTIZ DE ADLER; ANA G. ELIAS

Concepcion

Congreso; 6ta COLAGE, Conferencia LatinoAmericana de Geofísica Espacial; 2001

ALAGE, Asociacion LatinoAmericana de Geofisica Espacial

A search for a relationship between the tropical stratosphere temperature (TST) at 10 mb (~31 km), during the period 1959-1995 and the F10.7 cm solar flux has been carried out. The temperature anomalies relative to the 1961-1990 mean, TSTA, of four seasons: DJF, MAM, JJA and SON were considered. A 3-year moving average was applied to each series in order to remove the possible Quasi-Biennial Oscillation (QBO) influence. The linear correlation coefficient, r, between TSTA and F10.7 was calculated for each season, being 0.02, 0.26, 0.31 and 0.09 for DJA, MAM, JJA and SON respectively. These low values of r would indicate that there is not a significant influence of the solar cycle over the tropical stratosphere temperature at 10 mb. If each solar cycle is considered separately, r, for all the seasons, increase to values between 0.60 and 0.85 for cycles 20 and 21. The low values of r estimated with the whole period are due to the low linear association for cycle 22 (0.15 - 0.50). Noticeably, for each solar cycle, and for all the seasons, TSTA in terms of F10.7 follows an ordered loop pattern. Due to the loops are narrow for cycles 20 and 21, the relationship is closer to a linear one. Since the loops of cycle 22 are wide, the relationship is far from linear. These results would indicate that there exists a relationship between TSTA and F10.7.