Glacier change of the Columbia Icefield, Canadian Rocky Mountains, 1919–2009
Bibliographic record
Abstract
Abstract We determined length, area, elevation and volume change of the Columbia Icefield using Interprovincial Boundary Commission Survey maps from 1919, eight sets of aerial photographs from 1948 to 1993, and satellite data from 1999 to 2009. Over the period 1919–2009, glaciers on average retreated 1150 ± 34 m and shrank by 2.4 ± 0.2 km2. Total area loss was 59.6 ± 1.2 km2 (23 ± 5%), and mean elevation change was −49 ± 25 m w.e., resulting in a total volume loss of 14.3 ± 2.0 km3 w.e. Large outlet glaciers experienced the greatest absolute ice loss, while small, detached glaciers lost the most relative length and area. Thinning rates of debris-covered ice were 30–60% lower than those for clean ice. All glacier changes were significantly correlated with each other (p < 0.01), with r values ranging from 0.54 to 0.82. Temperature is correlated with length and area change over periods lagged 1–5 years (p < 0.05), and with elevation and volume change over periods lagged 9–18 years (p < 0.05). Precipitation is correlated with glacier change over periods lagged 1–10 years (p < 0.05).
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.003 |
| Science and technology studies | 0.002 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".