Land2Sea database of river drainage basin sizes, annual water discharges, and suspended sediment fluxes

Abstract

The Land2Sea database contains data on the sizes of 1519 exorheic river drainage basins (79% of the exorheic land area), annual suspended sediment fluxes (593 rivers, 63% of the exorheic land area), and water discharges (1272 rivers, 76% of the exorheic land area) that have been compiled from a variety of sources. The database extends earlier compilations, such as GEMS/GLORI. The river basins are grouped into 19 large‐scale drainage regions to investigate the regional variability in freshwater and sediment fluxes to various ocean basins. The annual suspended sediment flux to the coastal ocean (∼18.5 × 109 tons) is dominated by east Asia (6.1 × 109 tons); Arabia, India, and southeast Asia (4.3 × 109 tons); and eastern South America (2.4 × 109 tons). Small topical islands of Oceania support the highest annual sediment fluxes per drainage area (∼9650 t km−2 a−1). Annual freshwater discharge to the coastal ocean (∼38,857 km3) is dominated by runoff from eastern South America (11,199 km3); east Asia (7114 km3); and Arabia, India, and southeast Asia (4384 km3). The empirical data agree well with results from global models (ART and BQART) that have been trained on a subset of the data compiled here.