Solar output is only ONE of the natural variables I listed. The others include the Earth's orbital parameters which change constantly and periodically, but out of phase with one another. It is clear beyond any reasonable doubt that the Earth has been warming for about 10,000 years. Much of North America and Europe were under glaciers way back when. The methodology is solid and confirmed by glacial residues and other independent natual records. Up until the past couple of million years, massive continental glaciers had been absent for hundreds of millions of years. The "normal" or average climate of the Earth is subtropical nearly everywhere, when averaged over the past 540 million years since the beginning of the Cambrian. The current Ice Age is unlikely to last forever, and a return to much warmer temperatures is highly likely.