Organism
Columbia Glacier
TL;DR
A tidewater glacier in Alaska that serves as the chapter's primary biological case study.
A tidewater glacier in Alaska that serves as the chapter's primary biological case study. Stable for at least 200 years (possibly thousands) with terminus at 67km from source, Columbia Glacier began catastrophic retreat in 1982 after retreating off a shallow underwater ridge into deep water. Over 40 years (1980-2020), it retreated 20km - more than the previous 10,000 years combined. Calving frequency increased from every few weeks to multiple times per day, with house-sized blocks becoming stadium-sized.
Notable Traits of Columbia Glacier
- Stable for 200+ years before 1982 retreat
- Retreated 20km in 40 years (1980-2020)
- Calving frequency increased 10-100× during retreat
- Geometric trigger: retreat from shallow ridge into deep water