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Mazzarella A.,University of Naples Federico II | Giuliacci A.,University of Naples Federico II | Giuliacci A.,Epson Meteo Center | Scafetta N.,Active Cavity Radiometer Irradiance Monitor ACRIM Laboratory | Scafetta N.,Duke University
Theoretical and Applied Climatology | Year: 2013

The El Niño Southern Oscillation (ENSO) is the Earth's strongest climate fluctuation on inter-annual time scales and has global impacts although originating in the tropical Pacific. Many point indices have been developed to describe ENSO but the Multivariate ENSO Index (MEI) is considered as the most representative since it links six different meteorological parameters measured over the tropical Pacific. Extreme values of MEI are correlated to the extreme values of atmospheric CO2 concentration rate variations and negatively correlated to equivalent scale extreme values of the length of day rate variation. We evaluate a first-order conversion function between MEI and the other two indexes using their annual rate of variation. The quantification of the strength of the coupling herein evaluated provides a quantitative measure to test the accuracy of theoretical model predictions. Our results further confirm the idea that the major local and global Earth-atmosphere system mechanisms are significantly coupled and synchronized to each other at multiple scales. © 2012 Springer-Verlag.

Scafetta N.,University of Naples Federico II | Scafetta N.,Active Cavity Radiometer Irradiance Monitor ACRIM Laboratory | Scafetta N.,Duke University | Mazzarella A.,University of Naples Federico II
Natural Hazards | Year: 2015

We compare the NOAA Significant Earthquake Historical database versus typical climatic indices and the length of the day (LOD). The Pacific Decadal Oscillation (PDO) record is mainly adopted because most of the analyzed earthquakes occurred at the land boundaries of the Pacific Plate. The NOAA catalog contains information on destructive earthquakes. Using advanced spectral and magnitude squared coherence methodologies, we found that the magnitude M ≥ 7 earthquake annual frequency and the PDO record share common frequencies at about 9-, 20-, and 50- to 60-year periods, which are typically found in climate records and among the solar and lunar harmonics. The two records are negatively correlated at the 20- and 50- to 60-year timescales and positively correlated at the 9-year and lower timescales. We use a simple harmonic model to forecast the M ≥ 7 significant earthquake annual frequency for the next decades. The next 15 years should be characterized by a relatively high M ≥ 7 earthquake activity (on average 10–12 occurrences per year) with possible maxima in 2020 and 2030 and a minimum in the 2040s. On the 60-year scale, the LOD is found to be highly correlated with the earthquake record (r=0.51 for 1900–1994, and r=0.95 for 1910–1970). However, the LOD variations appear to be too small to be the primary earthquake trigger. Our results suggest that large earthquakes are triggered by crust deformations induced by, and/or linked to climatic and oceanic oscillations induced by astronomical forcings, which also regulate the LOD. © 2015, Springer Science+Business Media Dordrecht.

Mazzarella A.,University of Naples Federico II | Scafetta N.,Active Cavity Radiometer Irradiance Monitor ACRIM Laboratory | Scafetta N.,Duke University
Theoretical and Applied Climatology | Year: 2012

The North Atlantic Oscillation (NAO) obtained using instrumental and documentary proxy predictors from Eurasia is found to be characterized by a quasi 60-year dominant oscillation since 1650. This pattern emerges clearly once the NAO record is time integrated to stress its comparison with the temperature record. The integrated NAO (INAO) is found to well correlate with the length of the day (since 1650) and the global surface sea temperature record HadSST2 and HadSST3 (since 1850). These findings suggest that INAO can be used as a good proxy for global climate change, and that a ~60-year cycle exists in the global climate since at least 1700. Finally, the INAO ~60-year oscillation well correlates with the ~60-year oscillations found in the historical European aurora record since 1700, which suggests that this ~60-year dominant climatic cycle has a solar-astronomical origin. © 2011 Springer-Verlag.

Scafetta N.,University of Naples Federico II | Scafetta N.,Active Cavity Radiometer Irradiance Monitor ACRIM Laboratory | Scafetta N.,Duke University
Astrophysics and Space Science | Year: 2014

During the last few years a number of works have proposed that planetary harmonics regulate solar oscillations. Also the Earth’s climate seems to present a signature of multiple astronomical harmonics. Herein I address some critiques claiming that planetary harmonics would not appear in the data. I will show that careful and improved analysis of the available data do support the planetary theory of solar and climate variation also in the critiqued cases. In particular, I show that: (1) high-resolution cosmogenic 10Be and 14C solar activity proxy records both during the Holocene and during the Marine Interglacial Stage 9.3 (MIS 9.3), 325–336 kyear ago, present four common spectral peaks (confidence level ⪆95 %) at about 103, 115, 130 and 150 years (this is the frequency band that generates Maunder and Dalton like grand solar minima) that can be deduced from a simple solar model based on a generic non-linear coupling between planetary and solar harmonics; (2) time-frequency analysis and advanced minimum variance distortion-less response (MVDR) magnitude squared coherence analysis confirm the existence of persistent astronomical harmonics in the climate records at the decadal and multidecadal scales when used with an appropriate window lenght (L≈110 years) to guarantee a sufficient spectral resolution to solve at least the major astronomical harmonics. The optimum theoretical window length deducible from astronomical considerations alone is, however, L⪆178.4 years because the planetary frequencies are harmonics of such a period. However, this length is larger than the available 164-year temperature signal. Thus, the best coherence test can be currently made only using a single window as long as the temperature instrumental record and comparing directly the temperature and astronomical spectra as done in Scafetta (J. Atmos. Sol. Terr. Phys. 72(13):951–970, 2010) and reconfirmed here. The existence of a spectral coherence between planetary, solar and climatic oscillations is confirmed at the following periods: 5.2 year, 5.93 year, 6.62 year, 7.42 year, 9.1 year (main lunar tidal cycle), 10.4 year (related to the 9.93–10.87–11.86 year solar cycle harmonics), 13.8-15.0 year, ∼20 year, ∼30 year and ∼61 year, 103 year, 115 year, 130 year, 150 year and about 1000 year. This work responds to the critiques of Cauquoin et al. (Astron. Astrophys. 561:A132, 2014), who ignored alternative planetary theories of solar variations, and of Holm (J. Atmos. Sol. Terr. Phys. 110–111:23–27, 2014a), who used inadequate physical and time frequency analyses of the data. © 2014, Springer Science+Business Media Dordrecht.

Scafetta N.,Active Cavity Radiometer Irradiance Monitor ACRIM Laboratory | Scafetta N.,Duke University
Journal of Atmospheric and Solar-Terrestrial Physics | Year: 2010

We investigate whether or not the decadal and multi-decadal climate oscillations have an astronomical origin. Several global surface temperature records since 1850 and records deduced from the orbits of the planets present very similar power spectra. Eleven frequencies with period between 5 and 100 years closely correspond in the two records. Among them, large climate oscillations with peak-to-trough amplitude of about 0.1 and 0.25°C, and periods of about 20 and 60 years, respectively, are synchronized to the orbital periods of Jupiter and Saturn. Schwabe and Hale solar cycles are also visible in the temperature records. A 9.1-year cycle is synchronized to the Moon's orbital cycles. A phenomenological model based on these astronomical cycles can be used to well reconstruct the temperature oscillations since 1850 and to make partial forecasts for the 21st century. It is found that at least 60% of the global warming observed since 1970 has been induced by the combined effect of the above natural climate oscillations. The partial forecast indicates that climate may stabilize or cool until 2030-2040. Possible physical mechanisms are qualitatively discussed with an emphasis on the phenomenon of collective synchronization of coupled oscillators. © 2010 Elsevier Ltd.

Scafetta N.,Active Cavity Radiometer Irradiance Monitor ACRIM Laboratory | Scafetta N.,Duke University
Earth-Science Reviews | Year: 2013

Power spectra of global surface temperature (GST) records (available since 1850) reveal major periodicities at about 9.1, 10-11, 19-22 and 59-62years. Equivalent oscillations are found in numerous multisecular paleoclimatic records. The Coupled Model Intercomparison Project 5 (CMIP5) general circulation models (GCMs), to be used in the IPCC Fifth Assessment Report (AR5, 2013), are analyzed and found not able to reconstruct this variability. In particular, from 2000 to 2013.5 a GST plateau is observed while the GCMs predicted a warming rate of about 2°C/century. In contrast, the hypothesis that the climate is regulated by specific natural oscillations more accurately fits the GST records at multiple time scales. For example, a quasi 60-year natural oscillation simultaneously explains the 1850-1880, 1910-1940 and 1970-2000 warming periods, the 1880-1910 and 1940-1970 cooling periods and the post 2000 GST plateau. This hypothesis implies that about 50% of the ~0.5°C global surface warming observed from 1970 to 2000 was due to natural oscillations of the climate system, not to anthropogenic forcing as modeled by the CMIP3 and CMIP5 GCMs. Consequently, the climate sensitivity to CO2 doubling should be reduced by half, for example from the 2.0-4.5°C range (as claimed by the IPCC, 2007) to 1.0-2.3°C with a likely median of ~1.5°C instead of ~3.0°C. Also modern paleoclimatic temperature reconstructions showing a larger preindustrial variability than the hockey-stick shaped temperature reconstructions developed in early 2000 imply a weaker anthropogenic effect and a stronger solar contribution to climatic changes. The observed natural oscillations could be driven by astronomical forcings. The ~9.1year oscillation appears to be a combination of long soli-lunar tidal oscillations, while quasi 10-11, 20 and 60year oscillations are typically found among major solar and heliospheric oscillations driven mostly by Jupiter and Saturn movements. Solar models based on heliospheric oscillations also predict quasi secular (e.g. ~115years) and millennial (e.g. ~983years) solar oscillations, which hindcast observed climatic oscillations during the Holocene. Herein I propose a semi-empirical climate model made of six specific astronomical oscillations as constructors of the natural climate variability spanning from the decadal to the millennial scales plus a 50% attenuated radiative warming component deduced from the GCM mean simulation as a measure of the anthropogenic and volcano contributions to climatic changes. The semi-empirical model reconstructs the 1850-2013 GST patterns significantly better than any CMIP5 GCM simulation. Under the same CMIP5 anthropogenic emission scenarios, the model projects a possible 2000-2100 average warming ranging from about 0.3°C to 1.8°C. This range is significantly below the original CMIP5 GCM ensemble mean projections spanning from about 1°C to 4°C. Future research should investigate space-climate coupling mechanisms in order to develop more advanced analytical and semi-empirical climate models. The HadCRUT3 and HadCRUT4, UAH MSU, RSS MSU, GISS and NCDC GST reconstructions and 162 CMIP5 GCM GST simulations from 48 alternative models are analyzed. © 2013 Elsevier B.V.

Scafetta N.,Active Cavity Radiometer Irradiance Monitor ACRIM Laboratory | Scafetta N.,Duke University
Energy and Environment | Year: 2013

Global surface temperature records (e.g. HadCRUT4) since 1850 are characterized by climatic oscillations synchronous with specific solar, planetary and lunar harmonics superimposed on a background warming modulation. The latter is related to a long millennial solar oscillation and to changes in the chemical composition of the atmosphere (e.g. aerosol and greenhouse gases). However, current general circulation climate models, e.g. The CMIP5 GCMs, to be used in the AR5 IPCC Report in 2013, fail to reconstruct the observed climatic oscillations. As an alternate, an empirical model is proposed that uses: (1) a specific set of decadal, multidecadal, secular and millennial astronomic harmonics to simulate the observed climatic oscillations; (2) a 0.45 attenuation of the GCM ensemble mean simulations to model the anthropogenic and volcano forcing effects. The proposed empirical model outperforms the GCMs by better hind-casting the observed 1850-2012 climatic patterns. It is found that: (1) about 50-60% of the warming observed since 1850 and since 1970 was induced by natural oscillations likely resulting from harmonic astronomical forcings that are not yet included in the GCMs; (2) a 2000-2040 approximately steady projected temperature; (3) a 2000-2100 projected warming ranging between 0.3°C and 1.6°C, which is significantly lower than the IPCC GCM ensemble mean projected warming of 1.1°C to 4.1°C; (4) an equilibrium climate sensitivity to CO2 doubling centered in 1.35°C and varying between 0.9°C and 2.0°C.

Scafetta N.,Active Cavity Radiometer Irradiance Monitor ACRIM Laboratory | Scafetta N.,Duke University
Climate Dynamics | Year: 2014

Herein I propose a multi-scale dynamical analysis to facilitate the physical interpretation of tide gauge records. The technique uses graphical diagrams. It is applied to six secular-long tide gauge records representative of the world oceans: Sydney, Pacific coast of Australia; Fremantle, Indian Ocean coast of Australia; New York City, Atlantic coast of USA; Honolulu, US state of Hawaii; San Diego, US state of California; and Venice, Mediterranean Sea, Italy. For comparison, an equivalent analysis is applied to the Pacific Decadal Oscillation (PDO) index and to the Atlantic Multidecadal Oscillation (AMO) index. Finally, a global reconstruction of sea level (Jevrejeva et al. in Geophys Res Lett 35:L08715, 2008) and a reconstruction of the North Atlantic Oscillation (NAO) index (Luterbacher et al. in Geophys Res Lett 26:2745-2748, 1999) are analyzed and compared: both sequences cover about three centuries from 1700 to 2000. The proposed methodology quickly highlights oscillations and teleconnections among the records at the decadal and multidecadal scales. At the secular time scales tide gauge records present relatively small (positive or negative) accelerations, as found in other studies (Houston and Dean in J Coast Res 27:409-417, 2011). On the contrary, from the decadal to the secular scales (up to 110-year intervals) the tide gauge accelerations oscillate significantly from positive to negative values mostly following the PDO, AMO and NAO oscillations. In particular, the influence of a large quasi 60-70 year natural oscillation is clearly demonstrated in these records. The multiscale dynamical evolutions of the rate and of the amplitude of the annual seasonal cycle of the chosen six tide gauge records are also studied. © 2013 Springer-Verlag Berlin Heidelberg.

Scafetta N.,Active Cavity Radiometer Irradiance Monitor ACRIM Laboratory | Scafetta N.,Duke University
Physica A: Statistical Mechanics and its Applications | Year: 2014

Recently Gil-Alana et al. (2014) compared the sunspot number record and the temperature record and found that they differ: the sunspot number record is characterized by a dominant 11-year cycle while the temperature record appears to be characterized by a "singularity" or "pole" in the spectral density function at the "zero" frequency. Consequently, they claimed that the two records are characterized by substantially different statistical fractional models and rejected the hypothesis that the Sun influences significantly global temperatures. I will show that: (1) the "singularity" or "pole" in the spectral density function of the global surface temperature at the "zero" frequency does not exist - the observed pattern derives from the post 1880 warming trend of the temperature signal and is a typical misinterpretation that discrete power spectra of non-stationary signals can suggest; (2) appropriate continuous periodograms clarify the issue and also show a signature of the 11-year solar cycle (amplitude >deġC), which since 1850 has an average period of about 10.4 year, and of many other natural oscillations; (3) the solar signature in the surface temperature record can be recognized only using specific techniques of analysis that take into account non-linearity and filtering of the multiple climate change contributions; (4) the post 1880-year temperature warming trend cannot be compared or studied against the sunspot record and its 11-year cycle, but requires solar proxy models showing short and long scale oscillations plus the contribution of anthropogenic forcings, as done in the literature. Multiple evidences suggest that global temperatures and sunspot numbers are quite related to each other at multiple time scales. Thus, they are characterized by cyclical fractional models. However, solar and climatic indexes are related to each other through complex and non-linear processes. Finally, I show that the prediction of a semi-empirical model for the global surface temperature based on astronomical oscillations and anthropogenic forcing proposed by Scafetta since 2009 has, up to date, been successful. © 2014 Elsevier B.V. All rights reserved.

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