Major sources of North Atlantic Deep Water in the subpolar North Atlantic from Lagrangian particle experiments in a high–resolution ocean model
Bibliographic record
Abstract
North Atlantic Deep Water (NADW) is a crucial component of the Alantic Meridional Overturning Circulation and, therefore, is an important factor of the climate system. This thesis presents different aspects related to sources of NADW within the Western Boundary Current (WBC) system near 53°N. Lagrangian particle experiments were performed, utilising the high–resolution ocean model VIKING20X, in order to estimate mean relative contributions of different water mass sources within the subpolar North Atlanic. Furthermore, the pathways along which the associated water masses are transported and corresponding transit time scales were inferred. Virtual particles were traced backwards from a section near 53°N for 10 years and separated into different categories, depending on their respective sources. It was found that only about 12.0% of the particles originate from the mixed layer, where the Labrador Sea contribution dominates over the Irminger Sea contribution. Another 17.9% cross the Greenland–Scotland Ridge, where about 2/3 pass through Denmark Strait, while 1/3 cross the Iceland Scotland Ridge. Approximately 31:1% of the particles are associated with diapycnal mass flux, which therefore represents the largest source of NADW in the WBC system near 53°N. Almost 40% of the released particles, however, had no discernable source. This shows that large parts of the water masses require more than 10 years to reach the WBC system in the Labrador Sea. The experiments also show that particles belonging to the residuum tend to travel through the basin interiors, whereas particles attributable to any specified source appear to be strongly concentrated within the boundary currents. Furthermore, it is shown that particles that can be attributed to any of the specified sources, mostly contribute to water masses in the WBC system within the upper 1;500 to 2;000 m. The deeper water masses in the presented experiments are strongly dominated by the particle residuum, which also contributes significantly at shallower depths.
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 distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 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 teacher head, 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".