Entry_ID: G02203
Entry_Title: Arctic Sea Ice Charts from Danish Meteorological Institute, 1893 - 1956
Group: Data_Set_Citation
   Dataset_Creator: Danish Meteorological Institute and National Snow and Ice Data Center.  Compiled by V. Underhill and F. Fetterer. 
   Dataset_Title: Arctic Sea Ice Charts from Danish Meteorological Institute, 1893 - 1956
   Dataset_Release_Date: 2012-11-15
   Dataset_Release_Place: Boulder, Colorado USA
   Dataset_Publisher: NSIDC: National Snow and Ice Data Center
   Online_Resource: http://nsidc.org/data/g02203.html
   Dataset DOI: http://dx.doi.org/10.7265/N56D5QXC
End_Group
Group: Personnel
   Role: Technical Contact
   First_Name: NSIDC
   Last_Name: User Services
   Email: nsidc@nsidc.org
   Phone: 1 303 492-6199 x
   Fax: 1 303  492-2468 x
   Group: Contact_Address
      Address: National Snow and Ice Data Center
      Address: CIRES, 449 UCB
      Address: University of Colorado
      City: Boulder
      Province_or_State: CO
      Postal_Code: 80309-0449
      Country: USA
   End_Group
End_Group
Group: Personnel
   Role: Investigator
   Last_Name: Unknown
   Group: Contact_Address
      Address: Danish Meteorological Institute
      Address: Lyngbyvej 100 DK-2100
      City: Copenhagen E
      Country: Denmark
   End_Group
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Oceans
   Term: Sea Ice
   Variable_Level_1: Ice Extent
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Oceans
   Term: Sea Ice
   Variable_Level_1: Sea Ice Concentration
End_Group
ISO_Topic_Category: Climatology/Meteorology/Atmosphere
Keyword: Sea Ice
Keyword: Sea Ice Conditions
Keyword: Sea Ice Extent
Group: Temporal_Coverage
   Start_Date: 1893-04-01
   Stop_Date: 1956-08-31
End_Group
Data_Set_Progress: complete
Group: Spatial_Coverage
   Southernmost_Latitude: 55
   Northernmost_Latitude: 90
   Westernmost_Longitude: -180
   Easternmost_Longitude: 180
End_Group
Group: Location
   Location_Category: OCEAN
   Location_Type: ARCTIC OCEAN
End_Group
Group: Quality

   Especially early in the century, these charts are based on relatively sparse 
   data and rely to a large degree on the inference and extrapolation of the lead 
   mapmakers: V. Garde, C. Speerschneider, and H. Thomsen and M.V.L.Lorck 
   (Thomsen, 1947). Direct observations are always clearly marked, but white 
   space denotes the assumed ice edge. Directly observed open water is not shown 
   differently than assumed open water. Details on areas of open water can be 
   found in the notes that accompany the charts. In most cases, this assumed ice 
   edge follows a 30-year climatological average over a period of years that 
   shifts over the record. We do not have a refernce or any more information on 
   the 30-year climatology. However, the assumed ice edge moves independent of 
   the climatological average line. This suggests that the mapmakers incorporated 
   more factors than just an average estimate. As suggested by Kelly (1979), the 
   mapmakers probably extrapolated the annual ice edge in three ways: they 
   probably used their knowledge of ice movement, growth, and melt to project ice 
   conditions from given data points further in both time and space. They also 
   may have used auxiliary data that are not included in the DMI publications 
   themselves; these sources may have included annual climatic or atmospheric 
   circulation data present at the time. The DMI mapmakers were experienced 
   climatologists, so while their inferences are subjective, they are also 
   probably the most reliable of the time.

End_Group
Data_Set_Language: English
Group: Data_Center
   Data_Center_Name: NSIDC > National Snow and Ice Data Center
   Data_Center_URL: http://nsidc.org
   Group: Personnel
      Role: Data Center Contact
      First_Name: NSIDC
      Last_Name: User Services
      Email: nsidc@nsidc.org
      Phone: 1 303 492-6199 
      Fax: 1 303  492-2468 
      Group: Contact_Address
         Address: National Snow and Ice Data Center
         Address: CIRES, 449 UCB
         Address: University of Colorado
         City: Boulder
         Province_or_State: CO
         Postal_Code: 80309-0449
         Country: USA
      End_Group
   End_Group
End_Group
Group: Data_Center
   Data_Center_Name: NOAA > National Oceanic and Atmospheric Administration
   Data_Center_URL: http://nsidc.org/noaa/
   Group: Personnel
      Role: Data Center Contact
      First_Name: NOAA
      Last_Name: User Services
      Email: nsidc@nsidc.org
      Phone: 1 303 492-6199 x
      Fax: 1 303  492-2468 x
      Group: Contact_Address
         Address: National Snow and Ice Data Center
         Address: CIRES, 449 UCB
         Address: University of Colorado
         City: Boulder
         Province_or_State: CO
         Postal_Code: 80309-0449
         Country: USA
      End_Group
   End_Group
End_Group
Group: Distribution
   Distribution_Media: FTP
   Distribution_Size: 4.5 MB
   Distribution_Format: Joint Photographic Expert Group (JPEG) (.jpg)
End_Group
Group: Reference

   Chapman, W.L., and J.E. Walsh. 1991, updated 1996. Arctic and Southern Ocean 
   sea ice concentrations. Boulder, CO: National Snow and Ice Data Center 
   http://nsidc.org/data/g00799.html.

   Dehn, W. S. 1979. Inadequacies in Archive Sea Ice Data. Glaciological Data 
   Report : Workshop on Snow Cover and Sea Ice Data. GD-5 p 101-106. World Data 
   Center A for Glaciology (Snow and Ice). Boulder, CO.

   Kelly, P. M. 1979. An Arctic Sea Ice Data Set: 1901-1956. Glaciological Data 
   Report : Workshop on Snow Cover and Sea Ice Data. GD-5 p 101-106. World Data 
   Center A for Glaciology (Snow and Ice). Boulder, CO.

   Walsh, J.E. (1978) A data set on Northern Hemisphere sea ice extent. National 
   Snow and Ice Data Center, "Glaciological Data, Report GD-2", part 1, pp. 49 - 
   51. 

   Sear, C. B. 1988. An Index of Sea Ice Variations in the Nordic Seas. Int. J. 
   Climatology 8: 339-55.

   Thompson, H. 1947. The Annual Reports on the Arctic Sea Ice issued by the 
   Danish Meteorological Institute. J. of Glaciology 1(3): 140-141.

End_Group
Group: Summary

   From 1893 to 1956, the Danish Meteorological Institute (DMI) created charts of 
   observed and inferred sea ice extent for each summer month. These charts are 
   based on compiled observations of ice conditions reported by a variable 
   network of national organizations, shore-based observers, scientific 
   expeditions, and ships as detailed in each report; in cases where no 
   observations were available, the lead mapmakers extrapolated further ice cover 
   using their knowledge of ice movement. Except for where direct observations 
   are indicated, caution is advised in using the charts’ ice edge because there 
   is no way to quantify the assumptions used in extrapolating ice edge or the 
   error involved in this method. See the note on reliability for further 
   discussion of potential error. The charts were scanned at the Icelandic 
   Meteorological Office (IMO) and are being made available here as a service and 
   in cooperation with DMI and other contributors. In all, there are 266 image 
   files containing 291 images.

End_Group
Group: Related_URL
   Group: URL_Content_Type
      Type: VIEW RELATED INFORMATION
   End_Group
   URL: http://nsidc.org/data/g02140.html
   Group: Description

       Morphometric Characteristics of Ice and Snow in the Arctic Basin: Aircraft 
      Landing Observations from the Former Soviet Union, 1928-1989

   End_Group
End_Group
Group: Related_URL
   Group: URL_Content_Type
      Type: VIEW RELATED INFORMATION
   End_Group
   URL: http://nsidc.org/data/g02172.html
   Description:  National Ice Center Arctic Sea Ice Charts and Climatologies in Gridded Format
End_Group
Group: Related_URL
   Group: URL_Content_Type
      Type: VIEW RELATED INFORMATION
   End_Group
   URL: http://nsidc.org/data/g02176.html
   Description:  Sea Ice Charts of the Russian Arctic in Gridded Format, 1933-2006
End_Group
Group: Related_URL
   Group: URL_Content_Type
      Type: VIEW RELATED INFORMATION
   End_Group
   URL: http://nsidc.org/data/g02182.html
   Description:  Sea Ice Edge Location and Extent in the Russian Arctic, 1933-2006
End_Group
Group: Related_URL
   Group: URL_Content_Type
      Type: VIEW RELATED INFORMATION
   End_Group
   URL: http://nsidc.org/data/g01111.html
   Description:  The Dehn Collection of Arctic Sea Ice Charts, 1953-1986
End_Group
Metadata_Name: CEOS IDN DIF
Metadata_Version: 9.7
DIF_Creation_Date: 2012-11-15
Last_DIF_Revision_Date: 2013-03-12
DIF_Revision_History:  Added DOI to metadata record