Pictures of various sea ice types / surface types for the exemplification of the different conditions encountered: from left to right: cake ice, brash ice & pancake ice close to the ice edge, new ice (here: grease ice), first-year ice with melt ponds & new ice (here: dark nilas) & open water, multiyear ice, thin ice (here: dark nilas), multiyear ice & fresh lead, thin ice (here: light nilas). Please see the tutorial for a much better selection of different ice types and how they look like.
This data set is a collection of visual ship-based sea-ice observations carried out from the ship's bridge while the ship cruises through the sea ice. These observations have been standardized according to the ASPeCt protocol. These observations contain the ship's position, the day and time of the observation (hourly, with an observation radius around the ship of about 1 km), the total sea ice concentration, the partial concentrations of the three thickest sea ice types, and for these, respectively, thickness, type, degree of deformation, floe size, and snow properties and depth.
For more information see: http://www.aspect.aq
A tutorial allows to learn how sea-ice observations are carried out according to the ASPeCt protocol.
The two pictures at the top illustrate how the sea ice thickness is estimated by looking at the tilted ice floe and a scale attached to the ship's hull (in this case the research icebreaker Polarstern).
Coverage, spatial and temporal resolution
Period and temporal resolution:
Coverage and spatial resolution:
The header of the data files informs about the parameters included and in which column they are given in the data file. Data of different cruises are given in chronological order; the beginning of a new (cruise) data set is indicated at the first line of the respective data set (see references).
This data indicate the mean, typical sea ice type along the ship's cruise track; this data can not be recommended for a point validation.
This data is based on a visual estimation of the mentioned parameters and/or the parameters given in the data file and the tutorial.
The accuracy is therefore quite low: sea ice concentrations are given in 10% intervals; observation quality of sea ice type, degree of deformation, and floe size depend much more on the skills and experience of the observer, than estimates of ice thickness and snow depth.
Name: Stefan Kern
Institute: CliSAP / KlimaCampus / ICDC
email: stefan.kern@ zmaw.de
Name: Anthony Worby
Institute: Australian Antarctic Division and ACE CRC, University of Tasmania
email: A.Worby@ utas.edu.au
Should this data be used in a publication / report / presentation it is asked to cite as follows:
The ship-based sea ice and snow thickness data were provided by the SCAR Antarctic Sea Ice Processes and Climate (ASPeCt) program (www.aspect.aq)