This paper just published Has global warming already arrived? by C.A.Varotsos and M.N.Efstathiou (H/T Dennis Bird) Excerpts in italics with my bolds.
• The global warming during 1978–2018 was not more enhanced at high latitudes near the surface.
• The intrinsic properties of the lower stratospheric temperature are not related to those in the troposphere.
• The results obtained do not reveal the global warming occurrence.
The enhancement of the atmospheric greenhouse effect due to the increase in the atmospheric greenhouse gases is often considered as responsible for global warming (known as greenhouse hypothesis of global warming). In this context, the temperature field of global troposphere and lower stratosphere over the period 12/1978–07/2018 is explored using the recent Version 6 of the UAH MSU/AMSU global satellite temperature dataset.
Our analysis did not show a consistent warming with gradual increase from low to high latitudes in both hemispheres, as it should be from the global warming theory. In addition, in the lower stratosphere the temperature cooling over both poles is lower than that over tropics and extratropics. To study further the thermal field variability we investigated the long-range correlations throughout the global lower troposphere-lower stratosphere region. The results show that the temperature field displays power-law behaviour that becomes stronger by going from the lower troposphere to the tropopause.
This power-law behaviour suggests that the fluctuations in global tropospheric temperature at short intervals are positively correlated with those at longer intervals in a power-law manner. The latter, however, does not apply to global temperature in the lower stratosphere. This suggests that the investigated intrinsic properties of the lower stratospheric temperature are not related to those of the troposphere, as is expected by the global warming theory.
From the analysis presented above the following conclusions could be drawn:
• The temperature trend shows a decreasing warming from the lower troposphere up to the tropopause level and then reverses to cooling in the lower stratosphere. This trend at the tropopause can be considered almost zero. The latter can not support the increase in the height of tropopause, a ﬁngerprint of global warming.
• At the lower stratosphere there is a negative temperature trend which is lower over both poles (compared to tropics and extra-tropics) with the lowest value over the North Pole.
• In the lower and mid-troposphere the temperature trend decreases with height and latitude
The above-mentioned three results do not agree with the global warming theory, namely, the gradual increase of tropospheric warming with latitude.
The DFA and MDFA analyses conducted on the possible association of warming in the global troposphere with cooling in the global lower stratosphere showed the following:
• The temperature ﬂuctuations in the global troposphere exhibit power-law behaviour with an exponent gradually increasing with altitude reaching the unity at the tropopause.
• The global lower stratospheric temperature anomalies do not exhibit long-range correlation behaviour. In particular, the lower stratospheric temperature anomalies over tropics obey power-law behaviour, while it is not the case for the low stratospheric temperature anomalies over both poles. This may be attributed to the ozone dynamics in this region.
The two above-mentioned results lead to the main conclusion that the intrinsic properties of the thermal regime in the lower stratosphere are not associated with the thermal regime in the troposphere.In summary, the tropospheric temperature has not increased over the last four decades, in both hemispheres, in a way that is more ampliﬁed at high latitudes near the surface. In addition, the lower stratospheric temperature did not decline as a function of latitude. Finally,the intrinsic properties of the tropospheric temperature are diﬀerent from those of the lower stratosphere.
Based on these results and bearing in mind that the climate system is complicated and complex with the existing uncertainties in the climate predictions, it is not possible to reliably support the view of the presence of global warming in the sense of an enhanced greenhouse eﬀect due to human activities
via Science Matters
November 9, 2018 at 11:09AM