Himalayan ice-core dating with snow algae

Snow algae in shallow ice cores (7 m long) from Yala Glacier in the Langsta ng region of Nepal were examined for potential use in ice-core dating. Ice- core samples taken at 5350 m a.s.l. in 1994 contained more than seven speci es of snow algae. In a vertical profile of the algal biomass, 11 distinct a lgal layers were observed. Seasonal observation in 1996 at the coring site indicated most algal growth occurred from late spring to late summer. Pit o bservation in 1991, 1992 and 1994 indicated that algal layer formation take s place annually. delta O-18, chemical ions (Na+, Cl-, SO42- and NO3-) and microparticles failed to show any clear seasonal variation, particularly at depths exceeding 2 m, possibly due to heavy meltwater percolation. Snow al gae in ice cores would thus appear to be accurate boundary markers of annua l layers and should prove useful for ice-core dating in Himalayan-type glac iers.