Blog: Science NASA Study Acknowledges Solar Cycle, Not Man, Responsible for Past Warming Michael Andrews - June 4, 2009 9:37 AM Print 148 comment(s) - last by pvandyke.. on Jun 16 at 5:52 PM Recipient E-mail Sender E-mail Please input the letters/numbers that appear in the image below. (not case-sensitive) Past studies have shown that sunspot numbers correspond to warming or cooling trends. Th