A Thousand Degrees below Zero by Murray Leinster

New York was frightened, and the newspapers as they appeared did not / allay that fear. The conservative _Tribunal_ ran a scare head: HAS / THE GLACIAL AGE COME AGAIN? and printed underneath a résumé of the / phenomena up to the time of going to press -- which did not include the / appearance of the black flyer -- with an interview from a prominent / scientist. An enterprising reporter had routed the worthy gentleman out / of bed and rushed him to the scene of the expanding ice cake in a fast / motor boat, taking down in shorthand his comments on the matter. The / scientist had been much puzzled, but spoke at length nevertheless. He / said in part:

Has the glacial age come again? I do not know. I can only say that / we have no certain knowledge of the original cause of the glacial / period and we cannot say definitely that it did not begin in / precisely this fashion. We have volcanos which radiate incredible / quantities of heat to the country surrounding them. No phenomenon / like this has occurred before, but it may be that some unknown / cause may bring to the surface a condition the antithesis of a / volcano, which, instead of radiating heat, will bring on local / glacierlike conditions. One might go farther and suggest that the / earth may alternate between periods of volcanic activity, during / which it is warm and conditions are favorable for habitation and / growth, and periods of this new antivolcanic activity during which / frigidity is normal, and mankind may be forced to take refuge in / the tropic zones. Still, I cannot say definitely.