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CMIP5 CCSM4 Last Glacial Maximum dates

Hello,I am currently using CMIP5 CCSM4 last glacial maximum data, but I am confused on the exact dates of the data. For example one of the files I am using is hurs_Amon_CCSM4_lgm_r1i1p1_180001-190012.nc. When I load the data and view the layers, I can see that there are around 1000 monthly averages for 100 years, but the date represented in the meta data says that it runs from 1800 - 1900, which is not LGM (should be around 20,000 years ago). However when I downloaded the file from ESGF, the "model documentation" says that it starts "around" 19000 and runs for 100 years. Does anyone know the actual dates for the CCSM4 lgm model runs?  Thank you,Bailey MorrisonUniversity of Illinois at Urbana ChampaignGlobal Environmental Analysis and Remote Sensing Lab
 
Also, the files says that it has no coordinate reference system and I cannot figure out what the spatial units are. We believe they are in meters, but I cannot find that information any where since it spatially it is unit less. Reprojecting it has not helped. 
 

strandwg

Moderator
Staff member
The model's dates are somewhat arbitrary; in this instance they are merely a model time counter and not referenced to an absolute calendar. You can treat this simulation as 100 years of model time under LGM conditions.
 

strandwg

Moderator
Staff member
The geographic axes are degrees east (for longitude) and degrees north (for latitude). The earth is treated a perfect sphere of 6.37122 * 10^6 m radius. There is no "coordinate reference system" as is commonly used in GIS applications.You may want to contact the GIS group here https://gisclimatechange.ucar.edu/ For guidance on how best to use CESM model output with GIS. 
 
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