Entry_ID: GGD282
Entry_Title: Rock glaciers, Western Andes, Chile
Group: Data_Set_Citation
   Dataset_Creator: Kammer, K
   Dataset_Title: Rock glaciers, Western Andes, Chile
   Dataset_Release_Date: 1998-01-01
   Dataset_Release_Place: Boulder, Colorado USA
   Dataset_Publisher: NSIDC: National Snow and Ice Data Center
   Online_Resource: http://nsidc.org/data/ggd282.html
End_Group
Group: Personnel
   Role: Investigator
   First_Name: Klaus
   Last_Name: Kammer
   Email: jenny@giub.unibe.ch or imhof@giub.unibe.ch
   Group: Contact_Address
      Address: University of Bern
      Address: Institute of Geography, Paleoecology Group
      Address: Hallerstrasse 12
      City: Bern
      Postal_Code: CH-3012
      Country: Switzerland
   End_Group
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Cryosphere
   Term: Frozen Ground
   Variable_Level_1: Ground Ice
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Cryosphere
   Term: Frozen Ground
   Variable_Level_1: Periglacial Processes
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Cryosphere
   Term: Frozen Ground
   Variable_Level_1: Permafrost
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Cryosphere
   Term: Frozen Ground
   Variable_Level_1: Rock Glaciers
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Land Surface
   Term: Frozen Ground
   Variable_Level_1: Ground Ice
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Land Surface
   Term: Frozen Ground
   Variable_Level_1: Periglacial Processes
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Land Surface
   Term: Frozen Ground
   Variable_Level_1: Permafrost
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Land Surface
   Term: Frozen Ground
   Variable_Level_1: Rock Glaciers
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Paleoclimate
   Term: Land Records
   Variable_Level_1: Glaciation
End_Group
Keyword: Ground Ice
Keyword: Mapping
Keyword: Paleoclimate
Keyword: Periglacial Processes
Keyword: Permafrost Properties
Keyword: Remote Sensing
Keyword: Rock Glaciers
Group: Spatial_Coverage
   Southernmost_Latitude: -29
   Northernmost_Latitude: -18
   Westernmost_Longitude: -72
   Easternmost_Longitude: -67
End_Group
Group: Location
   Location_Category: CONTINENT
   Location_Type: SOUTH AMERICA
   Location_Subregion1: CHILE
   Detailed_Location: CHILEAN ALTIPLANO, WESTERN (CHILEAN) ANDES
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: FGDC > Frozen Ground Data Center
   Data_Center_URL: http://nsidc.org/fgdc/
   Group: Personnel
      Role: Data Center Contact
      First_Name: FGDC
      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_Format: PDF
End_Group
Group: Distribution
   Distribution_Media: FTP
   Distribution_Format: ASCII Text (.txt)
End_Group
Group: Reference

   Jenny B., Kammer K. 1996: Jungquartre Vergletscherungen. Geographica 
   Bernensia, in Ammann et al. 1996: Climate Change in den trockenen Anden. G46 
   Ammann C, 1996: Aktuelle Niederschlagsmuster. Geographica Bernensia 1996: 
   Climate Change in den trockenen Anden. G46 Kammer K., Ammann C.: Rock glaciers 
   in the Western Andes between 18-29S and climatic implications (in prep.)

End_Group
Group: Summary

   The research area is located along a transect from 18 deg S to 29 deg S in the 
   Chilean Altiplano, the western part of the high intramontane plateau in the 
   Central Andes. This region is located in an extremely arid zone between the 
   tropical and westerly circulation belt. The so-called 'Andean Dry Diagonal' 
   crosses the research area from NW to SE. 

   Over 120 rock glaciers have been mapped from chosen test sites using aerial 
   photographs. Several rock glaciers were visited in the field to compare the 
   results. From the collected data (height above sea level, exposition, 
   activity, latitude) we tried to conclude (paleo-)climatic implications. The 
   distribution was compared with summer and winter precipitation patterns of the 
   research area. The highest number of observed rock glaciers appears in the 
   north and very south of the transect--18 and 29 deg S. Between 23 and 27 deg S 
   there is a sharp decline in the number of rock glaciers. It coincides with the 
   present-day position of the 'Dry Diagonal' in the Western Andes. Most of the 
   mountains in this section have no rock glaciers, although there is sufficient 
   debris supply available. Focusing on activity, altitude, and latitude of the 
   observed rock glaciers north of 24 deg S, respectively, south of 27 deg S 
   there is a domination of active and inactive rock glaciers in comparison to 
   relict rock glaciers.

   On the other hand, there are no active rock glaciers between 24 and 27 deg S. 
   In this part, relict rock glaciers can lie 800 m higher than the estimated 
   annual 0-degree C isotherm. If we compare rock glacier activity and number 
   with the precipitation pattern of the area we note that the biggest number of 
   active rock glaciers lie in the region with highest precipitation rates. In 
   the driest part of the test area where the Andean Dry Diagonal crosses the 
   Western Andes there are no active rock glaciers. They can be found in areas 
   with estimated annual precipitation rates of 200 mm and more. Most of the 
   observed rock glaciers lie in ice free cirques. These were probably built up 
   after, or at, the time of a general ice decay. For the northern part between 
   18 and 24 deg S, we suggest glacier advances during the so-called Tauca-phase 
   at 12,000-8,000 yr BP. The majority of the rock glaciers in this area can only 
   have formed after 8,000 yr BP. In the southern part of the research area at 29 
   deeg S, we dated a late Holocene glacier advance at 2,600 yr BP, and thus rock 
   glaciers must have formed at the time of the general ice decay after 2,600 yr 
   BP.

   The altitude of active rock glaciers in the Chilean Andes between 18 and 29 
   deg S corresponds to the trend of the annual degree C isotherm, with a sharp 
   interruption in the driest zone between 24 and 27 deg S. In this part with 
   less than 100 mm precipitation/yr, the annual 0-degree  C isotherm has no 
   control on rock glacier activity -- the observed relict and inactive rock 
   glaciers lie distinctly higher. The driest zone of the research area 
   corresponds with the area with a striking reduction of number of rock glaciers 
   and also coincides with the zone where no active rock glaciers could be found. 
   We conclude that the so-called 'Andean Dry Diagonal' cannot have changed 
   significantly it's position since the time when the rock glaciers were formed, 
   probably in the middle and late Holocene. But we assume an intensification of 
   precipitation to form rock glaciers in the driest part of the research area. 
   These data are presented on the CAPS Version 1.0 CD-ROM, June 1998.

End_Group
Metadata_Name: CEOS IDN DIF
Metadata_Version: 9.7
DIF_Creation_Date: 1998-01-01
Last_DIF_Revision_Date: 2012-08-24
DIF_Revision_History: added creator and publisher info