Solar activity-climate relations during solar cycle 24

Abstract

Solar activity refers to every single Sun’s phenomenon, such as development of sunspots, solar flares, prominences etc. As determined by the number of sunspots, solar activity varies over an 11-year period. In this study, we examined the general distribution of thermosphere climate index (TCI) with respect to sunspot number during Solar Cycle 24 to obtain the pattern of thermal condition in thermosphere over the 11 years. Sunspot number, thermosphere climate index (TCI), mean temperature of surface air, and three latitudes, all obtained from NASA and NOAA, were used for this analysis. Our study found that sunspot number and TCI are directly correlated, meaning that low sunspot numbers during SC24 rising phase caused the thermosphere to cool off with low TCI readings and high sunspot numbers during solar maximum caused the thermosphere to heat up with high TCI levels. A low TCI reading of 0.25 W was recorded during solar minimum since fewer solar events penetrated the thermosphere, particularly magnetized plasma and radiation. At peak levels, Northern Hemisphere (NH) had a temperature anomaly of 1.6°C, Tropics had a temperature anomaly of 1°C, and Southern Hemisphere (SH) had a temperature anomaly of 0.6°C. Due to the lower sunspot number recorded throughout the 11 years, SC24 also happened to have the lowest TCI among many preceding cycles. There was a major correlation between the amount of plasma ejections during a specific phase and whether the thermosphere received much or little magnetized plasma. Along with SC24, mean temperatures for surface air and three latitudes also showed a gradual increase trend.