Citazione Originariamente Scritto da steph Visualizza Messaggio
I 4 eventi di El Nino più forti degli ultimi 150 anni sono stati quelli (in ordine cronologico inverso) del 2015/16, 1997/98, 1982/83 e 1877/78. Non vedo legami con l'attività solare, considerando che il primo e l'ultimo sono capitati in un periodo di relativa quiescenza, gli altri due in un periodo più intenso, ma non nettamente più intenso di altri.
" 1. Soon et al., 2015 noted that if the urbanization effect is properly taken into account, one can conclude that solar variability is the dominant factor of Northern Hemisphere long-term temperature changes since at least 1881.

2. Zhao and Feng, 2014 reported that variations in solar activity play an important role in changes of climate over global scale during the last more than 100 years.

3. According to Harde (2014), the Sun is the main contributor to global warming of the last century.

4. Lüdeсke et al. (2014) showed that variations of Central European temperature after 1757 were likely governed by periodic oscillations resulted from intrinsic climatic dynamics.

5. Scafetta (2010) and Scafetta (2012) claimed that the global climate oscillations from 1950 to 2011 were appreciably influenced by astronomic planetary cycles, particularly by motion of Jupiter and Saturn.

6. Swanson and Tsonis, 2009 noted that in the period 1900-2000 Northern Hemisphere climate variability might be partly explained by chaotic dynamics.

7. Privalsky and Fortus (2011) modeled variations of global temperature during 1850- 2009 as an autoregressive process of the fourth order. They arrived at a conclusion that global warming of the last 150 years could be fully explained by natural climatic variability without any external forcing.

Conclusion

[I]t is reasonable to regard the global warming as a phenomenon exceptional from the point of view of intrinsic climatic oscillations, which need an additional external forcing factor for explanation. On the other hand, the statistical experiments showed that an appreciable part of the global warming might be a result of natural fluctuations of climatic system. … [O]ur results show that the contribution of these external factors (including greenhouse effect) to the global warming could be less than is often believed.

Changes in the solar radiation at the Earth’s surface (global brightening) might be important source of the warming of the last decades (Ogurtsov et al., 2012). "