Articles | Volume 20, issue 7
https://doi.org/10.5194/tc-20-3783-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/tc-20-3783-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
06 Jul 2026
Research article |
| 06 Jul 2026
| 06 Jul 2026
Uncertainty of the satellite-retrieved sea-ice area record and its trend
Andreas Wernecke
CORRESPONDING AUTHOR
University of Hamburg, Hamburg, Germany
Thomas Lavergne
Norwegian Meteorological Institute, Oslo, Norway
Stefan Kern
University of Hamburg, Hamburg, Germany
Dirk Notz
University of Hamburg, Hamburg, Germany
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The total Arctic sea-ice area (SIA), which is an important climate indicator, is routinely monitored with the help of satellite measurements. Uncertainties in observations of sea-ice concentration (SIC) partly cancel out when summed up to the total SIA, but the degree to which this is happening has been unclear. Here we find that the uncertainty daily SIA estimates, based on uncertainties in SIC, are about 300 000 km2. The 2002 to 2017 September decline in SIA is approx. 105 000 ± 9000 km2 a−1.
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Xiaoxu Shi, Dirk Notz, Jiping Liu, Hu Yang, and Gerrit Lohmann
Geosci. Model Dev., 14, 4891–4908, https://doi.org/10.5194/gmd-14-4891-2021, https://doi.org/10.5194/gmd-14-4891-2021, 2021
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The ice–ocean heat flux is one of the key elements controlling sea ice changes. It motivates our study, which aims to examine the responses of modeled climate to three ice–ocean heat flux parameterizations, including two old approaches that assume one-way heat transport and a new one describing a double-diffusive ice–ocean heat exchange. The results show pronounced differences in the modeled sea ice, ocean, and atmosphere states for the latter as compared to the former two parameterizations.
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Short summary
We analyse the types and size of uncertainties in satellite measurements of the global sea ice cover. These measurements give insights into the state of the climate system and quality of climate models. We derive uncertainties for one satellite product and compare it with other products. We find that offsets do play a role for measurements of the total sea ice cover, but also for estimates of its change. This calls for further investigations into the reasons for these offsets.
We analyse the types and size of uncertainties in satellite measurements of the global sea ice...
