New paper advancing the "bottom-up" mechanism as important for the observed solar signals in the atmosphere
http://journals.ametsoc.org/doi/abs/10.1175/JAS-D-12-0214.1
http://journals.ametsoc.org/doi/abs/10.1175/JAS-D-12-0214.1
Observed Tropospheric Temperature Response to 11-yr Solar Cycle and What It Reveals about Mechanisms
Jiansong Zhou and Ka-Kit Tung
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Using 54 yr of NCEP reanalysis global data from 1000 to 10 hPa, this study establishes the existence and the statistical significance of the zonal-mean temperature response to the 11-yr solar cycle throughout the troposphere and parts of the lower stratosphere. Two types of statistical analysis are used: the composite-mean difference projection method, which tests the existence of the solar cycle signal level by level, and the adaptive AR(p)-t test, which tells if a particular local feature is statistically significant at the 95% confidence level. A larger area of statistical significance than that in previous published work is obtained, due to the longer record and a better trend removal process. It reveals a spatial pattern consistent with a “bottom up” mechanism, involving evaporative feedback near the tropical ocean surface and tropical vertical convection, latent heating of the tropical upper troposphere, and poleward large-scale heat transport to the polar regions. It provides an alternative to the currently favored “top down” mechanism involving stratospheric ozone heating.