Read here. The IPCC Climategate scientists have long had marching orders from their political masters to prove that human CO2 emissions are the principal cause of global warming. This politically correct agenda thus requires that IPCC scientists diminish or ignore other climate influencers, including solar.
Unfortunately for the IPCC, there still exist thousands of scientists who conduct objective climate research to determine the real causes of climate change, in spite of political agendas.
Recently, Chinese scientists reconstructed past temperatures and determined that swings in temperature averages are a result of multiple, natural oscillations that are driven by solar radiation variability. Their research does not implicate CO2 as a major contributing factor.
"In an attempt to gain that understanding, Qian and Lu began with the reconstructed global-mean temperature anomaly history of Mann et al. (2008), combined with HadCRUT3 data for 1000-2008, relative to 1961-1990...they used a wavelet transform procedure to identify four oscillations in the millennial temperature time series...Next, they similarly examined a reconstructed 400-year solar radiation series based on 10Be data...determined that "the ~21-year, ~115-year and ~200-year periodic oscillations in global-mean temperature are forced by and lag behind solar radiation variability," and they report that the "relative warm spells in the 1940s and the beginning of the 21st century resulted from overlapping of warm phases in the ~21-year and other oscillations," noting that "between 1994 and 2002 all four periodic oscillations reached their peaks and resulted in a uniquely warm decadal period during the last 1000 years,"...As for the future, they predict that "global-mean temperature will decline to a renewed cooling period in the 2030s, and then rise to a new high-temperature period in the 2060s."" [WeiHong Qian, Bo Lu 2010: Chinese Science Bulletin]
Additional solar-cosmic and peer-reviewed postings.