The more i read, the more are the proofs of a significant great shift in climatic behavior since the late 70' / early 80'.
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We have first the shift between temperature and solar irradiance. J.P. Rozelot and S. Lefebvre in "Is it possible to find a solar signature in the current climatic warming?" say :
The analysis was first conducted over the following three independent periods of time: 1856–1910, 1910–1945 and 1946–1975. An example is given in Fig. 2. The trends
obtained are given in Table 1 where the first line shows the values obtained for the temperature data and the sec- ond for the irradiance. A linear fit, as depicts in Fig. 3
(points represented by diamonds), gives a rather unexpected high correlation value of r = 0.98. It can be obviously objected that this may be fortuitous. The process was thus repeated for an other set of independent period of time, chosen in such a way that the trends in the temperatures are still significant: 1885–1940 and 1941–1975. At last we added two other sets, 1856–1887, 1856–1975. The linearity is still obtained.
Changes from 1861 to 1975 show an unexpected remarkable correlation, whereas the period 1976–2000 completely deviates from the previous analysis.
It can be illustrated by the following image :
Gray, L. J., et al. (2010), Solar influences on climate, Rev. Geophys., 48, RG4001
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Atmospheric layers : The cooling of the termopshere accelerated since the 80'.
If we only take the period starting at the 80', we have a greater cooling :
Zhang, S.-R., J. M. Holt, and J. Kurdzo (2011), Millstone Hill ISR observations of upper atmospheric long‐term changes: Height dependency, J. Geophys. Res., 116, A00H05
- The Mesosphere is also cooling since at least the early 80 ' (early data are more uncertain) :
Beig, G., et al., Review of mesospheric temperature trends, Rev. Geophys., 41(4), 1015, doi:10.1029/2002RG000121, 2003.
P. Kishore et al., Long-term trends observed in the middle atmosphere temperatures using ground based LIDARs and satellite borne measurements 2014
- The cooling of the stratosphere seems also to has accelerated since the late 70' :
Ramaswamy et al.: STRATOSPHERIC TEMPERATURE TREND 2001
Seidel, D. J., J. Li, C. Mears, I. Moradi, J. Nash, W. J. Randel, R. Saunders, D. W. J. Thompson, and C.-Z. Zou (2016), Stratospheric temperature changes during the satellite era, J. Geophys. Res. Atmos., 121
One can noted the suspension of the cooling trend in the stratosphere since the middle / late 90' mostly caused by the stagnation / decrease of ozone depletion gases like Chlorofluocarbones and thus, the stop of the decreasing ozone trend (In the upper atmosphere (AMSU 12, 13, 14 channels) it's more difficult to distinguished the trend because of the greater solar variability) :
D. W. J. Thompson, and C.-Z. Zou (2016), Stratospheric temperature changes during the satellite era, J. Geophys. Res. Atmos., 121
W. Steinbrecht et al. Ozone and temperature trends in the upper stratosphere at five stations of the Network for the Detection of Atmospheric Composition Change 2009
It is interesting to observe the synchronicity between the stratospheric "hiatus" and also the tropospheric "hiatus" occuring in the same time.
It make me think that one part of the increasing surface temperature since the 80' can be attributed to ozone depletion, allowing to more energetic UV to reach the surface and warm the ground and oceans.
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We have also a significant shift to a positive trend at the end of the 70' about oceans decadal oscilations :
No one realy knows what is the cause of this shift who affecte the earth and the entire atmosphere. I still found some hypotheses. For me, the most interesting is the study of Oliver, W. L., S.-R. Zhang, and L. P. Goncharenko (2013), Is thermospheric global cooling caused by gravity waves?
Manabe and Wetherald [1967] first showed that an increase in CO2 content in the atmosphere would heat the atmosphere below about the tropopause (by absorbing IR radiations from the ground) and cool the atmosphere above that level (by radiating thermal energy to space). Roble and Dickinson [1989] calculated the degree of cooling above 60 km altitude that one would expect for a doubling of greenhouse gas content at that altitude. They estimated a global mean cooling of 50 K near 350 km altitude. Holt and Zhang [2008], however, in considering the 1978–2007 database of incoherent scatter radar measurements of ion temperature collected at 375 km above Millstone Hill (43 ı N, 289 ı E), found a noontime cooling rate of 47 K per decade, or a 141 K decline over the span of their measurements. As the CO2 concentration increased only 12% during this time period, the simulation would estimate only an 6 K decline. Donaldson et al. [2010] conducted an independent analysis of the 1966–1987 Saint Santin (45 ı N, 2 ı E) radar database and confirmed the Holt and Zhang [2008] finding. In light of this stark factor-of-20 disagreement between theory and observation, processes other than CO2 cooling have been sought to explain the observations. Based on the Saint Santin data, Walsh and Oliver [2011] suggested some agency of O3 as the cooling source, based on the coincidence in time between the beginning of the temperature decline and the beginning of a strong decrease in O 3 content in the lower atmosphere. Laštovicka [2012] noted, however, that the longer 1978–2007 Millstone Hill data showed that the
temperature continued to decline beyond 1994, when the O3 content began a long recovery. [ 3 ] During our efforts to identify the cause of the great temperature decline in the thermosphere, we have noticed a correlation between the behavior of that temperature and the behavior of ENSO (El Niño–Southern Oscillation) activity, both in the timing of an onset of change, a subsequent linear trend, and decadal variations about that trend. This recognition has led us to ask if gravity waves, produced by wind action over the oceans and propagated to the upper atmosphere, may be responsible for cooling that upper region. Recent simulations [e.g., Yigit and Medvedev, 2009] show that gravity waves are expected to cool the thermosphere on the order of 100 K, the order of long-term cooling observed. We know of no other agency capable of cooling the thermosphere by that amount long term.
Why is the cooling so much larger than expected, (2) why has the cooling lasted so long, and (3) why is the thermospheric density response to the cooling so small? We have speculated that gravity waves may have caused this cooling, based on recent simulations that show that gravity waves are expected to cool the upper thermosphere by an amount comparable to the long-term cooling observed. A gravity wave proxy formed from the nontidal fluctuations in T° ion showed a positive long-term trend throughout its timeline, consistent with the increasing cooling observed. Fluctuations of T° ion about its long-term trendline were seen to anticorrelate both with fluctuations in the gravity wave proxy and with decadal fluctuations in El Niño–Southern Oscillation (ENSO) activity. The time scales of the long-term trend and the decadal fluctuations are characteristic of the ocean, not the atmosphere. We have suggested that the following scenario may explain these behaviors: (a) the climate regime shift of 1976–1977 launched slow Rossby waves across the oceans, waves which continue to propagate to this day; (b) winds over this increasingly corrugated ocean have launched increasing fluxes of gravity waves into the atmosphere; (c) these increasing fluxes of gravity waves have propagated to the thermosphere to produce increasing amounts of cooling; and (d) the decadal increases in winds associated with the decadal increases in ENSO activity have produced decadal increases in gravity wave fluxes, which, in turn, have caused decadal cooling in the thermosphere. The strong thermospheric cooling seen would be expected to produce thermospheric density declines much larger than those observed via satellite drag if the density at the base of the thermosphere were unchanging. We have noted that a lowering of the turbopause by about 4 km would raise atomic oxygen densities and completely compensate for that large expected density decline at 350 km altitude and referenced evidence of that lowering. We have asked if the heat pumped by gravity waves from the upper thermosphere to the lower thermosphere may augment the positive temperature gradient in the turbopause region, thereby making it more stable against the development of turbulence, and hence lowering the turbopause itself. Our proposed answers to our three posed questions are that the magnitude of the cooling is due to the agency of atmospheric gravity waves, that the length of the cooling is due to agency of ocean Rossby waves, and that the small density response is due to the lowering of the turbopause.
The ocean effect is a long-term transient response to forcing of unknown origin. The atmospheric effect is a steady state response to ocean forcing. This scenario may have validity, but it is unproved. The ocean Rossby wave source is purely speculative. Those Rossby waves, if they should exist, cannot be detected amongst the larger ocean eddies with current observational capabilities. (We ask if the very smallness of these ocean waves may be essential in that it leads to atmospheric gravity waves that are able to propagate to the upper thermosphere without growing to their breaking amplitude and dissipating at lower altitude.) For the existence of increasing amounts of gravity waves in the thermosphere, however, we have the evidence from our data of the increasing amounts of nontidal fluctuations in temperature. If the theorists and modelers [e.g., Walterscheid, 1981; Yi ̆git and Medvedev, 2009] are correct, this increasing gravity wave flux should increasingly cool the thermosphere. 42 ] These speculations need broad vetting by additional studies based on other data sets and of applicable theory. [ 43 ] We believe that the magnitude of the thermospheric temperature decline has been so great that the CO2 theory of its cooling cannot be maintained. It is certainly possible, however, that increased greenhouse warming at surface level has initiated the train of events that has led to the cooling by others means.
And it's not just only the El Niño–Southern Oscillation but almost all oscillations which have drifted in the same periode of time. So, if we consider this theory more or less true, we have still the need to find what cause the drift in the oceans. The C's have mentionned the cycle heating about the earth. When Pierre asked about El Nino, they said that it was powered by some space energetic flux. I give my tongue to the cat :P