Wednesday, October 07, 2009

Solar recession causes global cooling.

Our calculations provide the maximum semi-annual value of W in cycle 23
equal to 110–122 and the epoch of maximum in the first half of 2000. Hence, the
present cycle is not as high as was expected and predicted several years ago, nor as low as forecasted by some authors. This shows that the Gnevyshev–Ohl–Kopecký rule fails in this cycle. The end of the cycle is expected at 2006–2007. Proceeding from the current CGL brightness (the second half of 1999), we can predict a low cycle 24 with the maximal W not exceeding 50 (similar to cycles 5–6) and the epoch of maximum at 2010–2011. Thus, as inferred by our results, we are on the eve of a deep minimum of solar activity similar to that at the beginning of the 19th century.

BADALYAN et al 2000

One of the conundrums of the IPCC and the pro-contra arguments of AGW verses natural variability is with the sensitivity to Greenhouse gases,and the proportion of natural variability such as solar forcing.

There are many arguments, with the measurement problem ,solar variance such as TSI , volcanism, PDV etc

The main argument has been there is no trend in TSI(in the instrumental record) and if solar flux has not increased ,.Therefore the presumed causal mechanism is GHG..

One could then ask what happens if the sun enters a period of “Solar recession” an extended period of “inactivity” such as was seen during the maunder minimum and the little ice age of the 18-19th centuries.

As we observe in the botton graph, global temperatures have plateued and moved slightly negative in the last decade,and solar cycle 23 involved a decrease in TSI and a deep continuous minimum from which it is now possible to construct for the first time a trend in TSI which is negative and correlates to a decrease of 0.2w.

Evidence of a long-term trend in total solar irradiance
C. Fröhlich 2009

Aims. During the solar minimum of 2008, the value of total solar irradiance at 1AU (TSI) was more than 0.2Wm−2 lower than during the last minimum in 1996, indicating for the first time a directly observed long-term change. On the other hand, chromospheric indices and hence solar UV irradiance do not exhibit a similar change.
Methods. Comparison of TSI with other activity parameters indicates that only the open solar magnetic field, BR, observed from satellites at 1AU show a similar long-term behaviour. The values at the minima correlate well and the linear fit provides a direct physical relationship between TSI and BR during the minimum times.
Results. This correlation allows an unambiguous reconstruction of TSI back in time, provided the open solar magnetic field can be determined from e.g. geomagnetic indices or cosmogenic radionucleides. Since the solar UV irradiance has no long-term trend, the mechanism for the secular change of TSI must differ from the effect of surface magnetism, as manifested by sunspots, faculae, and network which indeed explain well the intra-cycle variability of both total and spectral irradiance. Conclusions. The long-term trend of TSI is most probably caused by a global temperature change of the Sun that does not influence the UV irradiance in the same way as the surface magnetic fields.

One might ask what is the rate of viscosity or contraction for an inverse forcing?


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