Ice sheets
SH circulation patterns shape Antarctic snowfall
Open access · cc by · source: Europe PMC
BAM, SAM, and PSA polarities rearrange Antarctic precipitation, with PSA1 explaining ~40% of daily variability in West Antarctica.
Study at a glance
- Design
- Other — Composites of RACMO2 Antarctic precipitation for BAM/SAM/PSA circulation phases (1979–2013)
- N
- 35-year reanalysis/model composite study; not a discrete sample N
- Population
- Antarctic Ice Sheet precipitation under Southern Hemisphere circulation modes
- Outcome
- Spatial precipitation rearrangements; PSA1 explaining ~40% of West Antarctic daily variance
Structured fields used in claim comparison tables when every cited study has a complete layer.
Key findings
BAM+ wets coastal East Antarctica; SAM+ wets the western Peninsula but dries the lee and the Plateau; PSA1+ can more than double Marie Byrd Land/Ross Ice Shelf precipitation. PSA1 accounts for ~40% of daily West Antarctic precipitation variance. Annual-mean index trends are not significant over 35 years.
Methodology
Authors composited 1979–2013 RACMO2 precipitation and ERA-Interim moisture fluxes for days when BAM, SAM, PSA1, or PSA2 indices exceeded ±1, and examined Byrd and Law Dome extremes.
Limitations
RACMO is still a model of precipitation, not gauges. Daily modes explain only modest fractions of day-to-day noise. 1979–2013 cannot project 21st-century SAM/PSA changes.
How this study connects
Role on claims
Each row is a claim on a concept or method page where this paper supports, challenges, or qualifies the statement. Roles are hand-checked — not a model guess.
This library holds 11 empirical papers on ice sheets with measured outcomes rather than reviews.
Evidence for the claim as stated.
BAM, SAM, and PSA polarities rearrange Antarctic precipitation, with PSA1 explaining ~40% of daily variability in West Antarctica.
Evidence for the claim as stated.
Atmospheric rivers and moisture fluxes are often defined on a reanalysis grid. A polar vIVT detector on MERRA-2 (1980–2020) attributed 374±90 Gt yr⁻¹, 13%±3% of Antarctic Ice Sheet precipitation, to ARs that occur <1.5% of the time; ERA-Interim moisture fluxes composited with RACMO2 showed PSA1 explaining about 40% of daily West Antarctic precipitation variance.
Evidence for the claim as stated.
Reanalysis precipitation over ice sheets is not interchangeable with ice-core chemistry. AR snowfall shares (13%±3%) are MERRA-2-based and not ice-core validated in that paper; the SH circulation paper uses RACMO2 precipitation, not gauges, and mentions Byrd and Law Dome as geographic extremes. A student who cites both as 'ice-core results' is mixing methods.
Evidence for the claim as stated.
The third paper in this index uses Byrd and Law Dome as named extremes in a 1979–2013 RACMO2/ERA-Interim composite of Southern Hemisphere circulation. Ice-core hits in the body are geographic, not a new core chemistry series. It belongs here as a caution about lexicon matching, and as a reminder that modelled precipitation at core sites is still a model.
Evidence for the claim as stated.
Measuring organics in a core, inverting published ice-core CH₄, and compositing modelled snowfall at core sites are three different uses of 'ice core.' The Bouvet paper is laboratory chemistry on ice; the methane paper is a box-model inversion of existing core time series; the circulation paper is not a core study. Combining them into one 'what ice cores show' paragraph would be a category error.
Evidence for the claim as stated.
Open questions
Tensions this paper is part of
From concept pages' “where studies disagree.” Disagreement means the same question; scope means different assays, populations, or outcomes.
Reanalysis precipitation over ice sheets is not interchangeable with ice-core chemistry. AR snowfall shares (13%±3%) are MERRA-2-based and not ice-core validated in that paper; the SH circulation paper uses RACMO2 precipitation, not gauges, and mentions Byrd and Law Dome as geographic extremes. A student who cites both as 'ice-core results' is mixing methods.
Measuring organics in a core, inverting published ice-core CH₄, and compositing modelled snowfall at core sites are three different uses of 'ice core.' The Bouvet paper is laboratory chemistry on ice; the methane paper is a box-model inversion of existing core time series; the circulation paper is not a core study. Combining them into one 'what ice cores show' paragraph would be a category error.
Related papers in this topic
Same topic cluster — not a recommendation engine.