GLACIAL AND PERIGLACIAL FEATURES

Late 20th century retreat
- Alpine Glaciers
- Greenland Ice Sheet

CIRQUES and MORAINES form at 0oC - -6oC mean summer temperature if moisture sufficient

Climate Reconstruction based on modern lapse rates
Modern Snow lines (Equilibrium Line Altitudes = ELA's) are compared with Glacial age elevations of cirques and moraines
Last Glacial Maximum ELA's were 1000 m lower
no Pleistocene snow lines at 30o N because mountains too low

Climatic Interpretation of ELA Lowering

PERIGLACIAL FEATURES:

patterns in soil and surface deposits resulting from permafrost

Modern Tibetan Plateau (INQUA International Symposium 1998)

LATE HOLOCENE GLACIAL ADVANCE & RETREAT

e.g., Quelccaya Ice Cap, Peru. 163.6 m thick, 1500 years old. (5670 m, -3oC) has now melted
Neoglacial (the last ca. 3500 years)
GLACIAL ADVANCES AS CAUSES OF CLIMATE:
Periglacial Readings

HOMEWORK