Global average is based on HADCRUT4 dataset (combined land and SST values). Data has been updated to V4 from V2.

Time Interval: Monthly
Time Coverage: 1856 to 2013
Update Status: Periodically updated

Get Data:

TAVEGL: Standard PSL Format (What is standard format?)
TAVEGL: Original Format

Source:
Data is from CRU via the page http://www.cru.uea.ac.uk/cru/data/temperature/.
References:
Many

1. See http://www.cru.uea.ac.uk/cru/data/temperature/#sciref

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