Expansion (version 2.0) of the original Land2Sea database of exorheic rivers (Peucker-Ehrenbrink, 2009, doi:10.1029/2008GC002356) that contains information on 1519 rivers, with additional literature estimates of basin size, water discharge (runoff) under current conditions and prior to human intervention, suspended sediment discharge under current conditions and prior to human intervention, estimate of sediment bedload flux, dissolved strontium concentration and radiogenic isotope value as well as particulate (silt or clay) neodymium concentration, isotope composition and Nd model ages. A large addition to the original river database that contains a significant amount of data from the compilation of Meybeck and Ragu (1996) is from Milliman and Farnsworth (2011). The compilation is not yet geo-referenced. The 2156 rivers are sorted alphabetically within each large-scale drainage region (Graham et al., 1999, 2000). In addition, the compilation includes data on sizes of, and sediment discharge from 48 small islands in Oceania with very high sediment yields.
Any errors in transcribing data or converting units from their primary sources into this compilation are entirely mine.
Acknowledgements: BPE acknowledges financial support from NSR-EAR-0087697, -0125873, -1226818 and ICER-1639557, as well as from WHOI's Investment in Research and Development Fund.
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Spatial Trends and Drivers of Bedload and Suspended Sediment Fluxes in Global Rivers
Bedload is notoriously challenging to measure and model; its dynamics, therefore, remains largely unknown in most fluvial systems worldwide. We present results from a global scale bedload flux model as part of the WBMsed modeling framework that well predict the distribution of water discharge, suspended sediment and bedload. The sensitivity of bedload predictions to river slope, particle size, discharge, river width, and suspended sediment were analyzed, showing the model to be most responsive to spatial dynamics in river discharge and slope. The relationship between bedload and total sediment flux is analyzed globally, and for representative longitudinal river profiles (Amazon, Mississippi, and Lena Rivers). The results show that while the proportion of bedload decreases from headwaters to the coasts, there is considerable variability between basins and along river corridors. The topographic and hydrological longitudinal profiles of rivers are shown to be the key drivers of bedload trends, with fluctuations in slope controlling its more local dynamics. Estimates of water and sediment fluxes to global oceans from 2,067 largest river outlets (draining 67% of the global continental area) are provided. Estimated water discharge at 30,579 km3/y corresponds well to past estimates; however, sediment flux is higher. Total global particulate load of 17.8 Gt/y is delivered to global oceans, 14.8 Gt/y as washload, 1.1 Gt/y as bedload, and 2.6 Gt/y as suspended bed material. The largest 25 rivers are predicted to transport more than half of the total sediment flux to global oceans.
more » « less- NSF-PAR ID:
- 10373247
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Water Resources Research
- Volume:
- 58
- Issue:
- 6
- ISSN:
- 0043-1397
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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