evidence: Even if the Sun’s recent quietness—the 11-year cycle minimum in 2011 was the lowest in a century—were to turn into a multi-decade stretch of extremely low activity known as a Grand Solar Minimum, it wouldn’t overpower the amount of global warming projected for the coming century due to increasing greenhouse gas emissions. In fact, as long as atmospheric carbon dioxide remains above 300 parts per million, not even the next ice age, which Milankovitch theory predicts would begin 50,000 years from now, is likely to occur. [...] Another study estimated that at pre-industrial carbon dioxide levels, summer insolation at 65° North need only dip 0.75 standard deviations below the mean—about 15 Watts per square meter—for summers to be too cool to melt all the winter snow, a low that Milankovitch cycles predict we will next hit about 50,000 years from now. At 400 parts per million, summer insolation would need to fall twice as much—a low we will next see 125,000 years from now. At carbon dioxide levels above 560 parts per million, the study predicted, no Milankovitch variation within the next half million years will be low enough to trigger an ice age. [...] Shakun, J. D., Clark, P. U., He, F., Marcott, S. A., Mix, A. C., Liu, Z., Otto-Bliesner, B., Schmittner, A., & Bard, E. (2012). Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation. Nature, 484(7392), 49–54. https://doi.org/10.1038/nature10915