Journal cover Journal topic
Ocean Science An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 2.289 IF 2.289
  • IF 5-year value: 2.756 IF 5-year 2.756
  • CiteScore value: 2.76 CiteScore 2.76
  • SNIP value: 1.050 SNIP 1.050
  • SJR value: 1.554 SJR 1.554
  • IPP value: 2.65 IPP 2.65
  • h5-index value: 30 h5-index 30
  • Scimago H index value: 41 Scimago H index 41
Discussion papers
https://doi.org/10.5194/os-2018-149
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-2018-149
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.

Research article 03 Jan 2019

Research article | 03 Jan 2019

Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Ocean Science (OS).

Validation metrics for ice edge position forecasts

Arne Melsom, Cyril Palerme, and Malte Müller Arne Melsom et al.
  • Norwegian Meteorological Institute

Abstract. The ice edge is a simple quantity in the form of a line that can be derived from a spatially varying sea ice concentration field. Due to its long history and relevance for operations in the Arctic, the position of the ice edge should be an essential element in any system that is designed to monitor or provide forecasts for the physical state of the Arctic Ocean and adjacent ocean regions.

Like for all components of monitoring and forecast products, users need to complement information about the ice edge position with the expected accuracy of the data or model results. Such information is traditionally available as a set of metrics that provide a concentrated assessment of the information quality. In this study we provide a survey of metrics that are presently included in the product quality assessment of the CMEMS Arctic Marine Forecasting Center sea-ice edge position forecast. We show that when ice edge results from different products are compared, mismatching results for polynya and local freezing at the coasts of continents and archipelagos have a large impact on the quality assessment. Such situations, which occur regularly in the products we examine, have not previously properly been acknowledged when a set of metrics for the quality of ice edge position results have been constructed.

We examine the quality of ice edge forecasts using a total of 17 metrics for the ice edge position. These metrics are analyzed in synthetic examples, in selected cases of actual forecasts, and for a full year of weekly forecast bulletins. Using necessity and simplicity of information as a guideline, we recommend using a set of four metrics that sheds light on the various aspects of product quality that we consider.

Moreover, any user is expected to be interested in a limited part of the geographical domain, so metrics derived as domain-wide integrated quantities may be of limited value. Consequently, we recommend that metrics are also made available for appropriate set of subdomains. Furthermore, we find that the metrics' decorrelation time scales are much longer than the present forecast range. Hence our final recommendation is to include depictions of gridded mismatching of ice edge positions using maps for the integrated ice edge error.

Arne Melsom et al.
Interactive discussion
Status: open (until 28 Feb 2019)
Status: open (until 28 Feb 2019)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement
Arne Melsom et al.
Arne Melsom et al.
Viewed  
Total article views: 159 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
135 20 4 159 10 3 2
  • HTML: 135
  • PDF: 20
  • XML: 4
  • Total: 159
  • Supplement: 10
  • BibTeX: 3
  • EndNote: 2
Views and downloads (calculated since 03 Jan 2019)
Cumulative views and downloads (calculated since 03 Jan 2019)
Viewed (geographical distribution)  
Total article views: 72 (including HTML, PDF, and XML) Thereof 72 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Cited  
Saved  
No saved metrics found.
Discussed  
No discussed metrics found.
Latest update: 20 Jan 2019
Publications Copernicus
Special issue
Download
Short summary
Retreating sea ice in the Arctic Ocean gives rise to increased naval traffic with shorter navigation distances. Hence, information about the position of the sea ice edge is crucial for safe navigation. In the present study we explore methods for examining the quality of sea ice edge forecasts. We conclude that the forecast quality can be monitored with results from a set of four quantities. We also recommend the use of maps which display discrepancies in the positions of the sea ice edge.
Retreating sea ice in the Arctic Ocean gives rise to increased naval traffic with shorter...
Citation
Share