Abstract: This data set comprises time series of the monthly sea-ice area (SIA) in the Northern Hemisphere (1 file) and in the Southern Hemisphere (1 file). SIA is derived from sea-ice concentration (SIC, also sea-ice area fraction) data of the following products: OSI SAF OSI-450a SIC climate data record / OSI-430a SIC interim climate data record, NOAA-NSIDC CDR, NASA-Team and Comiso-Bootstrap - all three from the NOAA/NSIDC SIC climate data record (version 4.0). The monthly SIA is either directly computed from monthly SIC data or is derived as the mean of all daily SIA values. If required, the observational gap at the pole is interpolated. If required, temporal interpolation is applied - both to fill temporal (up to a maximum of 7 consecutive days) and spatial (if less than 1000 non-contiguous missing grid cells per day) gaps.

Table of contents:

Northern Hemisphere: Comiso-Bootstrap monthly sea-ice area; NOAA-NSIDC CDR monthly sea-ice area; NASA-Team monthly sea-ice area; OSI SAF monthly sea-ice area

Southern Hemisphere: Comiso-Bootstrap monthly sea-ice area; NOAA-NSIDC CDR monthly sea-ice area; NASA-Team monthly sea-ice area; OSI SAF monthly sea-ice area

Technical Info: standard_name: sea-ice area; long_name: algorithm_specific hemispheric sea-ice area time-series; dimension: 2100; temporalExtent_startDate: 1850-01-01; temporalExtent_endDate: 2024-12-31; temporalResolution: monthly; spatialResolution: none; spatialResolutionUnit: none; horizontalResolutionXdirection: none; horizontalResolutionYdirection: none; verticalResolution: none; verticalResolutionUnit: none; verticalStart: none; verticalEnd: none; instrumentName: various SMMR SSM/I SSMIS; instrumentType: various multifrequency_microwave_radiometer; instrumentLocation: various Nimbus-7 DMSP-f8 DMSP-f11 DMSP-f13 DMSP-17; instrumentProvider: various 

Methods: See description on https://www.cen.uni-hamburg.de/en/icdc/data/cryosphere/uhh-sea-ice-area-product.html

Units (all variables): 1e6 km2

geoLocations:

Northern Hemisphere: westBoundLongitude: -180.0 degrees East; eastBoundLongitude: 180.0 degrees East; southBoundLatitude: 35.0 degrees North; northBoundLatitude: 90.0 degrees North; geoLocationPlace: Northern Hemisphere

Southern Hemisphere: westBoundLongitude: -180.0 degrees east; eastBoundLongitude: 180.0 degrees East; southBoundLatitude: -90.0 degrees North; northBoundLatitude: -35.0 degrees North; geoLocationPlace: Southern Hemisphere

Size:

Northern Hemisphere: 1 file, 4 variables, 2100 elements each (latest month with valid data is element 2099)

Southern Hemisphere: 1 file, 4 variables, 2100 elements each (latest month with valid data is element 2099)

Format: netCDF

DataSources:

https://doi.org/10.15770/EUM_SAF_OSI_0013 ; [last accessed: 2025-01-17]

https://doi.org/10.15770/EUM_SAF_OSI_0014 ; [last accessed: 2025-01-17]

https://nsidc.org/data/g02202 [last accessed: 2025-04-16]

Contact: uhhsia.ifm (at) uni-hamburg.de

Web page: https://www.cen.uni-hamburg.de/en/icdc/data/cryosphere/uhh-sea-ice-area-product.html

This data set can also be accessed from https://www.cen.uni-hamburg.de/en/icdc/data/cryosphere/uhh-sea-ice-area-product.html Note: The beginning of the time series (1850-01-01) was chosen to allow a more easy comparison to, e.g. , CMIP6 modeled sea-ice area of the historical or pi-control runs which usually begin 1850-01-01.