Hiroko Miyahara

Hiroko Miyahara studies long-term solar activity variations on centennial and longer timescales, as well as the underlying mechanisms, through the analysis of cosmic-ray-induced isotopes in tree rings, ice cores, and sediments. Her particular interests include the Grand Solar Minima, when the Sun experienced extremely weak activity conditions for decades.

A series of Grand Solar Minima from the 13th to the early 19th century is considered to have contributed to the occurrence of the Little Ice Age; however, the mechanisms explaining such a Sun-climate connection remain unsolved. To address this issue, she also works with various types of climate and meteorological records, including proxy-based, satellite-based, and literature-based data, to understand the Earth system’s response to solar forcing and the pathways of forcing. Through this research, she hopes to contribute to a comprehensive understanding of Earth as a system open to the nearby space environment.