Apparently previous studies of the sun-climate connection looked at the equatorial polar magnetic field which produces sun spots, but they did not consider the polar magnetic component of the solar dynamo. The polar fields are less strong than the equatorial fields, but it is claimed that the total magnetic fluxes of both fields are comparable. With proxy data they derive an empirical relation between tropospherical temperatures and solar equatorial and polar magnetic fields. The polar field could contribute about 30% as much as the equatorial field.
The paper, published in the Journal of Atmospheric and Solar-Terrestrial Physics focused on the period 1844-1960 (but extended at least one graph back to 1600) and finds our current warming period is not that different from earlier episodes and that the increase in solar activity in the last 400 years explains the warming, without any need to invoke a man-made enhanced greenhouse hypothesis.
“The amplitude of the present period of global warming does not significanty differ from the other episodes of relative warming.”
“1650 was the onset of the Maunder Minimum, 1835 was the Dalton Minimum”
“Around 1720 solar activity changed from a Grand Minimum into a period of Regular Oscillation”
“In 1923 the 20th century Grand Maximum started.”
Conclusions
“The three main results of this study are the following: First, there exists a relation between solar activity and average tropospheric temperatures. Next, this relation depends both on the toroidal and the poloidal component of solar magnetism. The seven temperature sets that we studied here, evidently give different results but it is gratifying that they agree qualitatively in confirming the dependence of tropospheric temperature on both components of solar activity. The third result is that a comparison of observed with calculated temperatures shows residual peaks and valleys. Some of these are significant, appearing in all seven data sets studied here.”
“These results may be of importance for understanding the solar mechanism(s) that influence(s) climate. The refereed literature contains 15 global or NH temperature data sets. Obviously all must be studied in order to further check the above results. It is also necessary to discuss the heliophysical and climatologic aspects of these findings. Such a study is presently underway with colleagues.”
REFERENCE
de Jager, C. and Duhau, S. 2009. Episodes of relative global warming. Journal of Atmospheric and Solar-Terrestrial Physics 71: 194-198. [PDF]
h/t via, NIPCC, then The Hockey Schtick (which has another graph from the paper), and then Menzies House. Thanks to all concerned (and especially to the person who sent me the email, which I can’t find).
Phenomenal Solar Eruption Today (see photo above)
Watch the Youtube of this hard-to-believe-it-could-be-this-big explosion. Wow. Just wow. It’s hard to get a grip on the scales involved.
No comments:
Post a Comment