2018/03/29 by Ying Mei, Hui Deng, Feng Wang · 19 citations
Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · #Astronomy #Astrophysics #Atmospheric sciences #Coronal hole #Coronal mass ejection #Flux (metallurgy) #Geomagnetism and Paleomagnetism Studies #Ionosphere and magnetosphere dynamics #Magnetic field #Magnetic flux #Meteorology #Photosphere #Physics #Rossby number #Rossby wave #Solar and Space Plasma Dynamics #Solar cycle #Solar wind #Spectral line #Sunspot #astro-ph.SR
paper · pdf · doi:10.1007/s10509-018-3306-1
published in Astrophysics and Space Science 363(4) (Springer Science+Business Media)
openalex publication_date 2018/03/29 · arxiv created 2018/11/12 · arxiv updated 2018/11/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Using the Hilbert-Huang transform technique, we investigate the midrange periodicities in solar radio flux at 2800 MHz (F10.7) and sunspot areas (SAs) from February 1, 1947 to September 30, 2016. The following prominent results are found: (1) The quasi-periodic oscillations of both data sets are not identical, such as the rotational cycle, the midrange periodicities, and the Schwabe cycle. In particular, the midrange periodicities ranging from 37.9 days to 297.3 days are related to the magnetic Rossby-type waves; 2) The 1.3-year and 1.7-year fluctuations in solar activity indicators are surface manifestations (from photosphere to corona) of magnetic flux changes generated deep inside the Sun; 3) At the timescale of the Schwabe cycle, the complicated phase relationships in the three intervals (1947-1958, 1959-1988, and 1989-2016) agree with the produced periodicities of the magnetic Rossby-type waves. \textbfThe findings indicate that the magnetic Rossby-type waves are the possible physical mechanism behind the midrange periodicities of solar activity indicators. Moreover, the significant change in the relationship between photospheric and coronal activity took place after the maximum of solar cycle 22 could be interpreted by the magnetic Rossby-type waves.