Geology

Biology

Ice shelf

Operating system

Geomorphology

Glacier

Oceanography

Sea ice

Geography

Ice calving

Cryosphere

Lactation

Pregnancy

Computer science

Climatology

Thinning

Forestry

Genetics

Speedup

Ice stream

Science Advances

Speedup of Pine Island Glacier over the past several decades has made it Antarctica's largest contributor to sea-level rise. The past speedup is largely due to grounding-line retreat in response to ocean-induced thinning that reduced ice-shelf buttressing. While speeds remained fairly steady from 2009 to late 2017, our Copernicus Sentinel 1A/B-derived velocity data show a >12% speedup over the past 3 years, coincident with a 19-km retreat of the ice shelf. We use an ice-flow model to simulate this loss, finding that accelerated calving can explain the recent speedup, independent of the grounding-line, melt-driven processes responsible for past speedups. If the ice shelf's rapid retreat continues, it could further destabilize the glacier far sooner than would be expected due to surface- or ocean-melting processes.

Ice-shelf retreat drives recent Pine Island Glacier speedup