Jaeger Monthly Mean Global Precipitation Climatology 2.5 x 5.0 degree V1 (RAIN_JEAGER) at GES DISC

The Jaeger Surface Rain Gauge Observations data set consists of gridded mean monthly global precipitation values for 1931 to 1960 over the continents and 1955 to 1965 over the oceans.

In order to calculate monthly, seasonal, and annual variations of precipitation over the whole globe, both hemispheres, and various meridional zones, a gridding technique was used on data spanning 1931 to 1960 over the continents, and 1955 to 1965 over the oceans. For the continental regions, the grid point values were obtained as eye estimates from isopleth maps prepared from up-to-date climatic atlases containing annual and monthly rainfall values, supplemented by other data sets. Although it was initially intended to use data for the standard period 1931-1960, this did not prove possible for all regions.

Moller's (1951) method for estimating rainfall frequencies was adopted to provide ocean precipitation data. Monthly percentage frequencies were extracted from the mapped isolines of the US Marine Climatic Atlas (US Naval Weather Service 1955-1965) and interpolated to the grid points. After re-expressing the monthly frequencies as annual percentages, the values were scaled to rainfall depth units using Geiger's (1965) precipitation map to yield monthly precipitation means.