Open AccessInsolation changes caused by combination of amplitude and frequency modulation of the obliquity
Author(s) -
Liu HanShou
Publication year - 1999
Publication title -
journal of geophysical research: solid earth
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/1999jb900246
Subject(s) - amplitude , orbital forcing , milankovitch cycles , insolation , geology , eccentricity (behavior) , physics , forcing (mathematics) , atmospheric sciences , modulation (music) , geophysics , atmosphere (unit) , climatology , environmental science , glacial period , meteorology , optics , paleontology , political science , law , acoustics
A forcing function is derived from the insolation signal with a bipolar pulse modulation train that is a function of Earth's obliquity. From this obliquity‐forced insolation, there is a calculated variation of about ±9% in the energy flux at the top of the atmosphere. Pulsations in the incoming solar radiation, induced by the amplitude‐frequency coupling effect of the obliquity, correlate well with continental biogenic silica data and the marine oxygen isotope record. The theory lends a new perspective to the physical mechanism involving climate change studies. Particularly, it provides a physical explanation of the 100‐kyr cycle in glaciation, which is distinct from the commonly considered variations in orbital eccentricity.