New paper finds another amplification mechanism by which the Sun controls climate

A paper published today in Environmental Research Letters finds changes in solar activity over the 11-year solar cycle modulate the Pacific–North American (PNA) influence on North American winter climate. According to the authors, "The PNA appears to play an important conduit between solar forcing and surface climate. The low solar (LS) activity may induce an atmospheric circulation pattern that resembles the positive phase of the PNA, resulting in a significant warming over northwestern North America and significant dry conditions in the Pacific Northwest, Canadian Prairies and the Ohio-Tennessee-lower Mississippi River Valley."

The paper adds to hundreds of other peer-reviewed publications finding solar amplification mechanisms by which tiny 0.1% changes of total solar irradiance can be amplified to produce large effects on climate via modulation of natural atmospheric and ocean oscillations such as the Southern Oscillation, North Atlantic Oscillation, Scandinavian Pattern, Quasi Biennial Oscillation (QBO), Indian Summer Monsoon, El Nino Southern Oscillation [ENSO], Pacific Decadal Oscillation, Pacific-North American Oscillation, East Asian Monsoon, Madden-Julian Oscillation, and others. Other amplification mechanisms include via ozone and sunshine hours/clouds.
Solar cycle modulation of the Pacific–North American teleconnection influence on North American winter climate

Zhongfang Liu1,2, Kei Yoshimura2, Nikolaus H Buenning3 and Xiaogang He

We investigate the role of the 11-year solar cycle in modulating the Pacific–North American (PNA) influence on North American winter climate. The PNA appears to play an important conduit between solar forcing and surface climate. The low solar (LS) activity may induce an atmospheric circulation pattern that resembles the positive phase of the PNA, resulting in a significant warming over northwestern North America and significant dry conditions in the Pacific Northwest, Canadian Prairies and the Ohio-Tennessee-lower Mississippi River Valley. The solar-induced changes in surface climate share more than 67% and 14% of spatial variances in the PNA-induced temperature and precipitation changes for 1950–2010 and 1901–2010 periods, respectively. These distinct solar signatures in North American climate may contribute to deconvolving modern and past continental-scale climate changes and improve our ability to interpret paleoclimate records in the region.