Neoglacial to recent glacier fluctuations on the volcano Popocatepetl, Mexico.

Abstract

Neoglacial to historic and recent fluctuations of the firn field and one glacier on Popocatepetl, include advance prior to 1519 to possible mid-Neoglaciation stadial position on gentle, north flanks at 4150m, then retreat up-valley to 4335m by 1906, and to 4435m by 1920 at 7 m/yr. After volcanic eruptions and melting to about 4800m in 192l, growth of firn field and advance of a thin ice lobe before 1949 to 4573m by 1950, then retreat in next 8 yr at about 34 m/yr, re-advance of the firn edge as an ice bulge to about 4700m by 1968, and as a thick doubled-lobed glacier to about 4600m by 1978 and 1979. A 37 yr crevasse study shows continuous active firn-field movement on the north-west side of the cone. -Author