Characteristic Time Scales of Decadal to Centennial Changes in Global Surface Temperatures Over the Past 150 Years

Abstract

We apply singular spectral analysis (SSA) to series of monthly mean values of surface air temperatures T, International sunspot number (ISSN), and polar faculae PF (1850-2017 for T and ISSN). The efficiency of the SSA algorithm that we use has been regularly improved. For the T, ISSN, and PF series, the SSA eigenvalues and first components are shown with their Fourier spectrum. Components of T, ISSN, or PF share similar periods. Most are found in solar activity. The~22-and~11-year components are modulated and drift in phase, reflecting slight differences in spectra. On the shorter-period side, components at~9,~5.5, and~4.7 years are in good agreement. They have been identified in solar activity. The 60-year component is prominent in T. It is not immediately apparent in ISSN but can be extracted with an appropriate choice of SSA window. Other types of data allow one to explore longer periods and confirm climatic variations at~60,~35, and~22 years and at 50-150 and 200-500 years. When we consider a longer ISSN series starting in 1700 and recalculate the SSA first component, the trends of solar activity and temperature over the time span from 1850 to 2017 are very similar, with slower rise before 1900 and after the late 1900s, separating a faster rise in much of the twentieth century. These trends, extracted over only 150 years, could be parts of longer, multicentennial changes in solar activity. Much of the variability of surface temperatures could be linked to the Sun.

On the Prediction of Solar Cycles

“…The closeness of Jupiter's revolution period and the Schwabe solar cycle has been noted since Wolf (1852). In our recent work, we have detected and/or confirmed the existence of ≈30 and ≈60 yr cycles in several geophysical series (Courtillot et al, 2013;Le Mouël, Lopes, and Courtillot, 2019a, 2019b, 2020bLe Mouël et al, 2019) and also in sunspots (Le Mouël, Lopes, and Courtillot, 2020a). These can be linked to Saturn's rotation period (as already noted by many authors, e.g.…”

“…We have recently detected oscillations with similar (pseudo-) periodicities in the SSA components of solar (Le Mouël, Lopes, and Courtillot, 2020a) and geophysical (Courtillot et al, 2013;Lopes, Le Mouël, and Gibert, 2017;Le Mouël, Lopes, and Courtillot, 2019a, 2019b, 2020bLe Mouël et al, 2019) phenomena. We now believe that this is due to forcing (excitation functions) by the planets (see Malburet, 1 2019, for one of the early such types of analysis), due to their enormous orbital moments (the Jovian planets carry more than 99.8% of the total orbital moment of the solar system, 87% of this being due to Jupiter and Saturn alone).…”

“…This lack of perfect periodicity of the cycle lends itself particularly well to SSA and the decomposition in components it leads to. On the other hand, this lack of periodicity Table 1 The column labeled Associated periods lists SSA periods of planetary revolutions, their harmonics, and commensurable periods (from Mörth and Schlamminger, 1979;Le Mouël, Lopes, and Courtillot, 2020a). The column labeled SSN pseudo cycles lists SSA periods of SSN (from Le Mouël, Lopes, and Courtillot, 2020a).…”

“…The SSA periods common to the Jovian planets of the solar system (periods of planetary revolutions and commensurable periods) and to SSN are given in Table 1 (from Mörth and Schlamminger, 1979;Le Mouël, Lopes, and Courtillot, 2020a).…”

“…In this paper, we vindicate that last statement. We propose a new way of predicting solar cycles that relies on the analysis of quasi-periodic components of the sunspot series using Singular Spectrum Analysis (SSA; see, e.g., Le Mouël, Lopes, and Courtillot, 2020a). Our method belongs to the third category, with a major addition (see Section 2).…”