Sea ice concentration distribution derived with the ASI algorithm from AMSR-E data in the northern (left) and southern (right) hemisphere for Sep. 27, 2011. Due to a malfunction of the antenna of the AMSR-E instrument there will be no further sea ice concentration maps available in the near future.
But: On http://www.seaice.de you can find near-real-time daily sea ice concentration maps derived from SSM/IS data using the ASI algorithm.
RESTRICTED only accessable in ZMAW network or via CliSAP login What does that mean?
Data access via file system: /data/icdc/ice_and_snow/asi_amsre_iceconc
Advanced Microwave Scanning Radiometer aboard EOS (AMSR-E) data have been used to produce a finer resolved sea-ice concentration data set gridded onto a polar-stereographic grid true at 70 degrees with 6.25 km grid resolution. The sea-ice concentration data available here have been computed by applying the ARTIST Sea Ice (ASI) algorithm to brightness temperatures measured with the 89 GHz AMSR-E channels. These channels have a considereably finer spatial resolution than the commonly used lower frequency channels.
So far there are no estimates of the uncertainties included in the data product.
Coverage, spatial and temporal resolution
Period and temporal resolution:
Coverage and spatial resolution:
The data set does not yet contain uncertainty estimates.
A number of comparisons with ship observations and independent satellite data (see publications listed below) have proven the skill of the ASI algorithm in particular for high sea-ice concentrations.
In addition a theoretical investigation about uncertainties that are expected due to sensor noise and/or varying surface and environmental conditions has been made; its results can be found in Spreen et al. (2008).
We note, that the advantage given with the finer spatial resolution could be offset sometimes by the higher uncertainty of the retrieved sea-ice concentration. This is caused by the higher sensitivity of the 89 GHz channels to the atmospheric water vapor content and the cloud liquid water content when compared to the usually used 37 GHz and 19 GHz channels. In particular in the marginal ice zone sea-ice concentration could therefore exhibit a positive bias.
CliSAP / ICDC:
CliSAP / KlimaCampus / Institute of Oceanography
Email: lars.kaleschke@ zmaw.de
CliSAP / KlimaCampus / ICDC
Email: stefan.kern@ zmaw.de
Jet Propulsion Laboratory
Please cite as
"ASI Algorithm AMSR-E sea ice concentration were obtained for [PERIOD] from the Integrated Climate Date Center (ICDC, http://icdc.zmaw,de/), University of Hamburg, Hamburg, Germany, [Month, Year]"