Modulation of Solar Wind Energy Flux Input on Global Tropical Cyclone Activity

TL;DR

This study explores how the solar wind energy flux input into Earth's magnetosphere influences global tropical cyclone activity, revealing a better correlation than traditional solar activity measures and suggesting a modulation mechanism.

Contribution

It is the first to link solar wind energy flux variations to tropical cyclone activity, highlighting a potential new factor in climate variability research.

Findings

Solar wind energy flux correlates better with cyclone activity than traditional solar parameters.

Tropical cyclones tend to be more intense during periods of higher geomagnetic activity.

Accumulated cyclone energy shows a long-term increase since 1963 and decrease after 1994.

Abstract

Studies on Sun-climate connection have been carried out for several decades, and almost all of them focused on the effects of solar total irradiation energy. As the second major terrestrial energy source from outer space, the solar wind energy flux exhibits more significant long-term variations. However, its link to the global climate change is rarely concerned and remain a mystery. As a fundamental and important aspect of the Earth's weather and climate system, tropical cyclone activity has been causing more and more attentions. Here we investigate the possible modulation of the total energy flux input from the solar wind into the Earth's magnetosphere on the global tropical cyclone activity during 1963--2012. From a global perspective, the accumulated cyclone energy increases gradually since 1963 and start to decrease after 1994. Compare to the previously frequently used parameters, e,g., the sunspot number, the total solar irradiation, the solar F10.7 irradiation, the tropical sea surface temperature, and the south oscillation index, the total solar wind energy flux input exhibits a better correlation with the global tropical cyclone activity. Furthermore, the tropical cyclones seem to be more intense with higher geomagnetic activities. A plausible modulation mechanism is thus proposed to link the terrestrial weather phenomenon to the seemly-unrelated solar wind energy input.