grid: /T (months since 1960-01-01) ordered (Jan 1901) to (Dec 1998) by 1.0 N= 1176 pts :grid
grid: /X (degree_east) periodic (179.75W) to (179.75E) by 0.5 N= 720 pts :grid
grid: /Y (degree_north) ordered (89.75S) to (89.75N) by 0.5 N= 360 pts :grid
Mark New, Mike Hulme, and Phil Jones, Representing Twentieth-Century Space–Time Climate Variability. Part I: Development of a 1961–90 Mean Monthly Terrestrial Climatology,Journal of Climate: Vol. 12, No. 3, pp. 829–856.