Variation of Ice Velocity at Lewis Glacier, Mount Kenya, Kenya: Verification Midway Into a Forecast

Abstract The ice velocity slowdown occurring at Lewis Glacier, Mount Kenya, during the twentieth century has continued beyond 1978. In an earlier paper, a surface velocity decrease approaching 50% was predicted between 1978 and 1985. Measurements to January 1982, halfway through the period, reveal trends generally in line with this forecast: a velocity reduction of order 20% has taken place. The mass flux decreased by at least 25%. Intra-annual variability in velocity pattern and magnitude is apparent; comparatively rapid values occur during the January–February dry season.