September 4, 2008
-----------------

Version 1 of the Level 2, 3, and 4 files for the ARM Southern Great Plains
(SGP) control site (US-ARc) were posted.

January 22, 2010
----------------

Version 2 for the L2 files were posted.  Version 2 provides the same data
as Version 1 except the new files include incoming global radiation (Rg)
estimates and the variable nomenclature and units in the latest L2 files
conform to the standards adopted for the network-wide AmeriFlux database.
Details on CDIAC's processing of the Level 1 files provided by the US-ARc
site investigators to produce these Level 2 files may be found at

ftp://cdiac.ornl.gov/pub/ameriflux/data/Level2/Sites_ByName/ARM_SGP_Control/with_gaps/report_ARM_SGP_Control.html