A global vector dataset of oases for Digital Earth

Oases are water-dependent landscape systems that support ecological processes and human activities in drylands. However, a global dataset delineating oasis boundaries and spatial distribution is still lacking. We constructed a global oasis vector dataset for the reference year 2020 through standardized visual interpretation of metre- to sub-metre-scale Google Earth imagery, supported by multiple auxiliary datasets. The dataset contains 3,437 oasis patches covering 2,272,595.47 km2. Field-survey validation and random hexagonal-grid validation yielded overall accuracies of 94.88% (95% CI: 93.12–96.20%) and 93.47% (95% CI: 93.02–93.90%), respectively. The results show that Asia contains the largest share of global oasis area, accounting for 65.67% of the total. Global oasis area is concentrated in a small number of countries, with the 10 countries having the largest oasis areas accounting for 66.77% of the global total. The Green Region class occupies 66.00% of the raster-overlay area within the oases, with cropland representing the dominant land-cover class. The dataset provides a reusable spatial baseline for dryland research, with potential applications in sustainability assessment, cross-regional synthesis, land-cover product validation, and oasis dynamics monitoring.