As you report, American scientists concerned with solar physics are now suggesting that the sun is going into a period of, as it were, hibernation (“Sun Down,” June 18, 2011). Something like this has already happened twice since records began some four centuries ago: from 1645 to 1715 and from 1790 to 1830. During these periods, global temperatures were lower than average. Several studies indicate that the quiet period may last about a decade. This is good news, as the cooling may counteract the effects of the greenhouses gases that people are now spewing into the atmosphere. As you put it, “whether the breathing space thus granted would be used wisely or squandered is another matter.” Indeed. The Industrial Revolution, which was initiated more than two centuries ago, is still going full blast, albeit far from its cradle in northwestern Europe. Throttling it would be unimaginable in countries like China, India, Russia, and Brazil. It would cause revolutions of other, much less politically palatable, variety. In short, the breathing space will be squandered. Alas!