Friday, January 31, 2014

New paper finds another solar amplification mechanism that controls climate

A paper published today in the Journal of Climate finds a "robust response" of the East Asian monsoon to short-term changes in solar activity over 11-year solar cycles. Using observations from the last 5 solar cycles, the authors find tiny 0.1% changes in solar irradiance are amplified to induce a shift in location and increased variability of the East Asian monsoon rain band. The East Asian monsoon in turn has profound effects on Asian climate and interacts with other global atmospheric oscillations. 

The paper adds to hundreds of other peer-reviewed publications finding solar amplification mechanisms via effects on natural atmospheric and ocean oscillations such as the Southern OscillationNorth Atlantic Oscillation, Scandinavian Pattern,Quasi Biennial Oscillation (QBO), Indian Summer Monsoon, El Nino Southern Oscillation [ENSO], East Asian Monsoon, Pacific Decadal Oscillation, Madden-Julian Oscillation, and others. Other amplification mechanisms include via ozone and sunshine hours/clouds.

Robust response of the East Asian monsoon rainband to solar variability

Liang Zhao1,2 and Jing-Song Wang1,*
1 National Center for Space Weather, Beijing, China 100081
2 Mailbox 5111, Beijing, China 100094
This study provides evidence of robust response of the East Asian monsoon rainband to 11-year solar cycle and first identify the exact time period within the summer half-year (1958–2012) with the strongest correlation between the mean latitude of the rainband (MLRB) over China and the sunspot number (SSN). This period just corresponds to the climatological mean East Asian Meiyu season, characterized by a large-scale quasi-zonal monsoon rainband (i.e., 22 May to 13 July). Both the statistically significant correlation and the temporal coincidence indicate a robust response of the Meiyu rainband to solar variability during the last five solar cycles. During the high-SSN years, the Meiyu MLRB lies 1.2° farther north and the amplitude of its interannual variations increases when compared with low-SSN years. The robust response of monsoon rainband to solar forcing is related to an anomalous general atmospheric pattern with an up-down seesaw and a north-south seesaw over East Asia.

1 comment:

  1. Another paper finding solar influence of the Asian Monsoon