Development and validation of the global map of irrigation areas

TLDR

It is an important dataset for global water and land‑use studies. The study presents the dataset, mapping methodology, and first country‑level quality estimates. The authors created a new digital global irrigation map by merging 10,825 sub‑national statistics with spatial data, producing 5‑arc‑minute cells indicating irrigation coverage around 2000. Two quality indicators were devised, and the map was validated against two remote‑sensing global land‑cover inventories. Abstract.

Abstract

Abstract. A new version of a digital global map of irrigation areas was developed by combining irrigation statistics for 10 825 sub-national statistical units and geo-spatial information on the location and extent of irrigation schemes. The map shows the percentage of each 5 arc minute by 5 arc minute cell that was equipped for irrigation around the year 2000. It is thus an important data set for global studies related to water and land use. This paper describes the data set and the mapping methodology and gives, for the first time, an estimate of the map quality at the scale of countries, world regions and the globe. Two indicators of map quality were developed for this purpose, and the map was compared to irrigated areas as derived from two remote sensing based global land cover inventories.