Sea ice concentration estimates from satellite passive microwave radiometry and openings from SAR ice motion
Open accessAbstract
Openings in the Arctic Ocean ice cover from small‐scale sea ice motion fields are compared with open water fractions retrieved from satellite passive microwave observations. We find very little agreement between the results. Passive microwave retrieval algorithms seem to be insensitive to small areas of open‐water in winter leads. Variability in the passive microwave retrievals is mostly due to anomalous and persistent regions of lower ice concentration where no openings are found. Between January and April of 1998, openings cover ∼0.3 ± 0.1% of the total area within the perennial ice zone. This is smaller, in one instance ten times, than the open water fraction from the passive microwave retrievals. Previous bounds of open water coverage of the ice cover imposed on climate simulations based on uncertainties in passive microwave retrievals (±4 − 7%) are too high and the over‐estimated open water fraction on model results should be re‐examined.
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
Locations for which the NT value is greater than 95 % are an acceptable representation of 100 % ice for selecting closed-ice training samples.
“As in Tonboe et al. (2016), the CI training sample is based on the results of the NASA Team (NT) algorithm (Cavalieri et al., 1984): locations for which the NT value is greater than 95 % are used as a representation of 100 % ice (Kwok, 2002).”
From Version 2 of the EUMETSAT OSI SAF and ESA CCI sea-ice concentration climate data records (2019) · cites this paper as Kwok, 2002
The Data Sets and Approach section identifies the NASA Team algorithm, but does not describe a >95% threshold or closed-ice training samples. The Results and Discussion and Conclusions discuss uncertainty in winter-pack ice concentrations, without assessing whether NT values above 95% can represent 100% ice. Searches for the threshold and training-sample criterion found no such passage in our copy. (LLM, conf=0.76)
Experimental — accuracy not yet measured
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
The self-check needs the paper’s full text.
Cites
No references could be resolved yet.
Research works printed but not linked: 3
- Kwok, R., Deformation of the Arctic Ocean sea ice cover: November 1996 through April 1997, in Scaling Laws in Ice Mechanics and Dynamics, edited by J. Dempsey, Kluwer Academic, in press.
- Kwok, R., and G. F. Cunningham, Seasonal ice area and volume production in the Arctic Ocean: November 1996 through May 1997, J. Geophys. Res., in press.
- Kwok, R., D. A. Rothrock, H. L. Stern, and G. F. Cunningham, Determina- tion of Ice Age using Lagrangian Observations of Ice Motion, IEEE Trans. Geosci. Remote Sens., 33(2), 392 -400, 1995.
Cited by
Sorted by citations
Version 2 of the EUMETSAT OSI SAF and ESA CCI sea-ice concentration climate data records
Lavergne, T., Sørensen, A. M., Kern, S., Tonboe, R., Notz, D., Aaboe, S., Bell, L., Dybkjær, G., Eastwood, S., Gabarro, C., et al. (2019) · The Cryosphere · doi:10.5194/tc-13-49-2019 · Cited by 469 · see citing works
“As in Tonboe et al. (2016), the CI training sample is based on the results of the NASA Team (NT) algorithm (Cavalieri et al., 1984): locations for which the NT value is greater than 95 % are used as a representation of 100 % ice (Kwok, 2002).”
Method
- Authors
- Kwok, R.
- Affiliations
- Jet Propulsion Laboratory (US)
- Corresponding author
- Kwok, Ron
- ORCID
- Kwok, Ron
- Venue
- Geophysical Research Letters
- Publisher
- American Geophysical Union (AGU)
- Published
- 2002-05
- Volume
- 29
- Issue
- 9
- ISSN
- 0094-8276 (ISSN-L)
- 1944-8007
- OpenAlex
- W1993845291
- Cited by
- 71
- References
- 0
- Citations by year
- 2024: 3 · 2023: 12 · 2022: 3 · 2021: 14 · 2019: 5 · 2018: 2 · 2017: 1 · 2016: 1 · 2015: 2 · 2014: 4 · 2013: 3 · 2012: 2
- FWCI
- 1.49
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Geophysical Research Letters (publishedVersion)
- Topics
- Physical Sciences › Earth and Planetary Sciences › Atmospheric Science › Arctic and Antarctic ice dynamics
- Physical Sciences › Earth and Planetary Sciences › Atmospheric Science › Cryospheric studies and observations
- Physical Sciences › Earth and Planetary Sciences › Oceanography › Oceanographic and Atmospheric Processes
- Keywords
- sea ice concentration, open water fraction, passive microwave retrieval, synthetic aperture radar, sea ice motion, lead, Arctic Ocean, retrieval uncertainty
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
