Willmott and Feddema's Moisture Index Archive:
Monthly Time Series (1950 - 1999)

(Version 1.01)

produced and documented by

Cort J. Willmott and Kenji Matsuura
(with support from NASA's Seasonal to Interannual ESIP)

For additional information concerning this archive,
please contact us at:

Center for Climatic Research
Department of Geography
University of Delaware
Newark, DE 19716
(302) 831-2294

or

kenjisan@udel.edu


Archive (Version 1.01) released July 1, 2001


GRIDDED DATA SOURCES:

Time series of gridded monthly total potential evapotranspiration (Eo) and total precipitation (P) were taken from the Terrestrial Water Budget Data Archive: Monthly Time Series (1950-1999) (Version 1.02) and the Terrestrial Air Temperature and Precipitation: Monthly and Annual Time Series (1950-1999) (Version 1.02), which also are available from this web site. The length of each grid-node time series is 50 years (from 1950 through 1999) and the grid points, which number 85,794, cover the globe at a 0.5x0.5 degree resolution.

GRIDDED WATER-BUDGET ESTIMATES:

Monthly moisture-index fields were estimated from the gridded monthly total Eo and total P fields according to Willmott and Feddema (1992) at the same resolution as the water-balance fields.

ARCHIVE STRUCTURE:

There is one file that includes the 50 yearly files. All yearly files have the same structure (once they are uncompressed). Please note that annual moisture index was computed from the 12-month totals of Eo and P.


Field Columns Variable Fortran Format
1 1 - 8 Longitude (decimal degrees)
F8.3
2 9 - 16 Latitude (decimal degrees)
F8.3
3-14 17 - 112 Monthly Moisture Indices
12F8.2
15 113 - 120 Annual Moiture Indices
F8.2


SELECTED REFERENCES:

Willmott, C. J., C. M. Rowe, and Y. Mintz, 1985b. Climatology of the Terrestrial Seasonal Water Cycle. Journal of Climatology, 5, 589-606.

Willmott, C. J. and J. J. Feddema, 1992. A More Rational Climatic Moisture Index. Professional Geographer, 44(1), 84-88.