Singer: 'Kerry also raises the specter that AGW is worse than weapons of mass destruction (WMD). So how many millions has AGW killed so far? If truth be told, a slightly warmer climate (since about 1850) and more carbon dioxide in the atmosphere have promoted more productive agriculture and may have saved many millions from starvation. Besides, the Medieval Warm Period (MWP) was warmer than today and permitted a higher standard of living. It was the Little Ice Age (LIA) that killed off millions by starvation and disease during 1400-1800.'