Millennial cycles of mean sea level excited by eart s orbital variations

Abstract

The millennial climate cycles are an important factor of global environmental changes. These cycles change the polar ice thickness during ice ages, what results in the Mean Sea Level (MSL) changes. The main cause of ice age periods are the so called Milankovich orbital cycles, generated by variations of climatic precession, eccentricity of the Earth's orbit and Earth's axial tilt with respect to its orbital plane with main periods of about 23 ka 1 , 40 ka and 100 ka, respectively. The common millennial cycles of MSL and Earth's orbit variations are studied by means of reconstructed MSL time series for the last 800 ka and insolation data of the latest orbital solution of Laskar et al. (2011). The models of the common millennial cycles of MSL and insolation variations are based on partial Fourier approximations with different period bands around 23 ka, 18ka, 11.5 ka, 7.5 ka, 6 ka and 2.3 ka, respectively. These models may help to analyze the Earth's rotation cycles caused by millennial solar activity cycles, such as Hallstatt cycles, and to point out new possible millennial cycles of the solar activity.

12th Workshop Solar Influences...

“…The time series of oscillations from a given frequency band are calculated as a superposition of two neighbor Fourier harmonics, whose coefficients are estimated by the Least Squares Method inside the Method of Partial Fourier Approximation (PFA). The details of the last method are described in (Chapanov et al, 2015).…”

Decadal cycles of Earth rotation, mean sea level and climate, extited by solar activity

“…The periodical variations are derived from the data by means of partial Fourier approximation based on the Least-Squares (LS) estimation of Fourier coefficients (Chapanov et al, 2015;Ron et al, 2012). The Partial…”

“Obstanovka” experiment on determining spacecraft surface charging aboard the International Space Station

“…The time series of oscillations from a given frequency band are calculated as a superposition of two neighbor Fourier harmonics, whose coefficients are estimated by the Least Squares (LS) Method. The details of this method are described in (Chapanov et al, 2015). Shortly, the Partial Fourier approximation   Ft of discrete data is given by…”

“…The time series spectra are calculated by the Fast Fourier Transform (FFT). The time series of oscillations with a given frequency are calculated by the Method of Partial Fourier Approximation (PFA), whose details are described in (Chapanov et al, 2015). The used time series cover 179-year overlapped time interval for CR and T since 1836, and 166-year overlapped time interval for TSI and T since 1850.…”