文档介绍：,beforeitcouldfalltothesnow,,¾howmuchcolderhedidnotknow. ToBuildaFire,,,,,itneverarrivesatsubtropicallatitudesascoldasinLondon',airmassesthatdominatedagivenlocationdeterminedthedegreetowhichhumansneededshelterandclothing,rewfood,'spowerfulengines,,runways,,,,andhave,,,thedirectiontheytypicallymovein,?Anairmassisanexpansivemassofairwithhomogeneousnear-surfaceweathercharacteristics,