Source:         Princeton University
Name:           Princeton Global PDSI
Period:         Jan-1948 - Dec-2008
Times:          monthly
Coverage:       Global
Resolution:     1.0-degree
Grid:           Latitude-longitude
Type:           Observational-Reanalysis hybrid driven PDSI
Related Sites:  http://hydrology.princeton.edu/data.php
Publications:   Sheffield, J., G. Goteti, and E. F. Wood, Development of a
                50-yr high-resolution global dataset of meteorological forcings for land
                surface modeling, J. Climate, 19 (13), 3088-3111.
		Sheffield, J., E. F. Wood, and M. L. Roderick, 2012: Little change in 
		global drought over the past 60 years. Nature, 491, 435–438. 
		doi:10.1038/nature11575.
Variables:      PDSI
                Potential Evaporation
Formats:        NetCDF
History:        Original data
Volume:         monthly: 181 MB/variable 
Date Created:   Jul 26 14:37:43 EDT 2013
Change Log:     

4) Jul 26 2013
Initial versions of the PDSI datasets uploaded. There are two types of PDSI (original
and self-calibrating (sc)), two versions of the algorithm for PE (Thornthwaite
and Penman-Monteith) and four versions of the precipitation forcing (CPC, CRU,
GPCC, Willmott).

3) Mar 27 2013
Both PE datasets updated to correct for minor bugs in the humidity inputs in
isolated grid cells and to correct for a data input problem for the version of
PE based on empirical radiation. Ignore previous versions.

2) Mar 18 2013
PE data uploaded. Two versions are available depending on the source of the
shortwave and longwave radiation: 1) using the updated PGF (Sheffield et al.,
2006) radiation data which is based on a merged and corrected NCEP-NCAR
reanalysis and SRB dataset. 2) using an empirical (based on humidity, cloud
cover) estimate of radiation (Sheffield et al., 2012).

1) Jan 14 2013
Initial version of PE data uploaded...