Testing an astronomically based decadal-scale empirical harmonic climate model versus the IPCC (2007) general circulation climate models

► The IPCC (CMIP3) climate models fail in reproducing observed decadal and multidecadal limate cycles. ► Equivalent cycles are found among the major oscillations of the solar system. ► A correction for the projected anthropogenic warming for the 21st century is proposed. ► A full empirical model is developed for forecasting climate change for a few decades since 2000. ► The climate will likely stay steady until 2030/2040 and may warm by about 0.3-1.2 °C by 2100.