Title

Arctic Monthly Mean Sea Ice Extent from Observations Reprocessing

Alternate title

ARCTIC_OMI_SI_extent_obs

Date (Creation)

2018-02-13

Edition

3.4

Edition date

2023-11-30

Citation identifier

092e4075-ec9d-4a4a-b8ca-6f988ff27834

Abstract

'''DEFINITION'''

Sea Ice Extent (SIE) is defined as the area covered by sufficient sea ice, that is the area of ocean having more than 15% Sea Ice Concentration (SIC). SIC is the fractional area of ocean that is covered with sea ice. It is computed from Passive Microwave satellite observations since 1979.

SIE is often reported with units of 106 km2 (millions square kilometers). The change in sea ice extent (trend) is expressed in millions of km squared per decade (106 km2/decade). In addition, trends are expressed relative to the 1979-2022 period in % per decade.

These trends are calculated (i) from the annual mean values; (ii) from the March values (winter ice loss); (iii) from September values (summer ice loss). The annual mean trend is reported on the key figure, the March and September values are reported in the text below.

SIE includes all sea ice, but not lake or river ice.

See also section 1.7 in Samuelsen et al. (2016) for an introduction to this Ocean Monitoring Indicator (OMI).

'''CONTEXT'''

Sea ice is frozen seawater that floats at the ocean surface. This large blanket of millions of square kilometers insulates the relatively warm ocean waters from the cold polar atmosphere. The seasonal cycle of sea ice, forming and melting with the polar seasons, impacts both human activities and biological habitat. Knowing how and by how much the sea ice cover is changing is essential for monitoring the health of the Earth. Sea ice has a significant impact on ecosystems and Arctic communities, as well as economic activities such as fisheries, tourism, and transport (Meredith et al. 2019).

'''CMEMS KEY FINDINGS'''

Since 1979, the Northern Hemisphere sea ice extent has decreased at an annual rate of -0.51 +/- 0.03106 km2 per decade (-4.41% per decade). Loss of sea ice extent during summer exceeds the loss observed during winter periods: Summer (September) sea ice extent loss amounts to -0.81 +/- 0.06 106 km2 per decade (-12.73% per decade). Winter (March) sea ice extent loss amounts to -0.39 +/- 0.03 106 km2 per decade (-2.55% per decade). These values are in agreement with those assessed in the IPCC Special Report on the Ocean and Cryosphere in a Changing Climate (SROCC) (Meredith et al. 2019, with estimates up until year 2018). September 2022 had the 11th lowest mean September sea ice extent. Sea ice extent in September 2012 is to date the record minimum Northern Hemisphere sea ice extent value since the beginning of the satellite record, followed by September values in 2020.

'''Figure caption'''

a) The seasonal cycle of Northern Hemisphere sea ice extent expressed in millions of km2 averaged over the period 1979-2022 (red), shown together with the seasonal cycle in the year 2022 (green), and b) time series of yearly average Northern Hemisphere sea ice extent expressed in millions of km2. Time series are based on satellite observations (SMMR, SSM/I, SSMIS) by EUMETSAT OSI SAF Sea Ice Index (v2.2) with R&D input from ESA CCI. Details on the product are given in the corresponding PUM for this OMI. The change of sea ice extent over the period 1979-2022 is expressed as a trend in millions of square kilometers per decade and is plotted with a dashed line in panel b).

'''DOI (product):'''

https://doi.org/10.48670/moi-00191

Credit

E.U. Copernicus Marine Service Information

Point of contact

Organisation name	Individual name	Electronic mail address	Role
SIW-METNO-OSLO-NO			Production Unit

Maintenance and update frequency

Annually

Other

P0M0D0H/P0M0D0H

Target Application

• target-application#seaiceinformation

GEMET - INSPIRE themes, version 1.0

• Oceanographic geographical features

Discipline

• satellite-observation

Climate and Forecast Standard Names

• sea_ice_extent

Temporal scale

• multi-year

Area of benefit

• weather-climate-and-seasonal-forecasting
• marine-resources
• marine-safety
• coastal-marine-environment

Reference Geographical Areas

• arctic-ocean

Processing level

• N/A

Model assimilation

• Not Applicable

Use limitation

See Copernicus Marine Environment Monitoring Service Data commitments and licence at: http://marine.copernicus.eu/web/27-service-commitments-and-licence.php

Access constraints

Other restrictions

Use constraints

License

Other legal constraints

No limitations on public access

Aggregate Datasetindentifier

8a8afc62-adee-4f49-bd6b-9247033769b3

Association Type

Cross reference

Initiative Type

Document

Aggregate Datasetindentifier

516f56c4-be25-4f0c-8cdc-69a04892d37e

Association Type

Cross reference

Initiative Type

Document

Aggregate Datasetindentifier

4df0e679-103e-430e-b2cc-e15241395f2b

Association Type

Cross reference

Initiative Type

Document

Title

Samuelsen, A., L.-A. Breivik, R.P. Raj, G. Garric, L. Axell, E. Olason (2016): Sea Ice. In: The Copernicus Marine Service Ocean State Report, issue 1, Journal of Operational Oceanography, 9:sup2, s235-s320, DOI: 10.1080/1755876X.2016.1273446

Date (Creation)

2019-05-08

Association Type

Cross reference

Initiative Type

Reference

Title

Meredith, M., M. Sommerkorn, S. Cassotta, C. Derksen, A. Ekaykin, A. Hollowed, G. Kofinas, A. Mackintosh, J. Melbourne-Thomas, M.M.C. Muelbert, G. Ottersen, H. Pritchard, and E.A.G. Schuur, 2019: Polar Regions. In: IPCC Special Report on the Ocean and Cryosphere in a Changing Climate [H.-O. Pörtner, D.C. Roberts, V. Masson-Delmotte, P. Zhai, M. Tignor, E. Poloczanska, K. Mintenbeck, A. Alegría, M. Nicolai, A. Okem, J. Petzold, B. Rama, N.M. Weyer (eds.)]. In press.

Date (Creation)

2019-05-08

Association Type

Cross reference

Initiative Type

Reference

Language

eng

Topic category

• Oceans

Description

bounding box

Begin date

1979-01-01

End date

2021-12-31

Supplemental Information

display priority: 53705

Reference system identifier

EPSG / WGS 84 (EPSG:4326)

Number of dimensions

2

Dimension name

Row

Dimension name

Column

Cell geometry

Area

Transformation parameter availability

Distribution format

Name	Version
NetCDF-4

OnLine resource

Protocol	Linkage	Name
WWW:STAC	https://stac.marine.copernicus.eu/metadata/ARCTIC_OMI_SI_extent_obs/arctic_omi_si_extent_obs_202311/dataset.stac.json	arctic_omi_si_extent_obs

Hierarchy level

Series

Statement

The myOcean products depends on other products for production or validation. The detailed list of dependencies is given in ISO19115's aggregationInfo (ISO19139 Xpath = "gmd:MD_Metadata/gmd:identificationInfo/gmd:aggregationInfo[./gmd:MD_AggregateInformation/gmd:initiativeType/gmd:DS_InitiativeTypeCode/@codeListValue='upstream-validation' or 'upstream-production']")

Attribute description

observation

Content type

Physical measurement

Descriptor

temporal resolution: monthly mean

Descriptor

vertical level number: 0

Included with dataset

Feature types

Point series

Metadata

File identifier

092e4075-ec9d-4a4a-b8ca-6f988ff27834

Metadata language

English

Character set

UTF8

Hierarchy level

Series

Hierarchy level name

Copernicus Marine Service product specification

Date stamp

2025-04-22T08:34:14.331071Z

Metadata standard name

ISO 19139, MyOcean profile

Metadata standard version

0.2

Metadata author

Organisation name	Individual name	Electronic mail address	Role
CMEMS		servicedesk.cmems@mercator-ocean.eu	Local service desk