James P. M. Syvitski

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Analysis of data from 280 rivers discharging to the ocean indicates that sediment loadslyields are a log-linear function of basin area and maximum elevation of the river basin. Other factors controlling sediment discharge (e.g., climate, runoff) appear to have secondary importance. A notable exception is the influence of human activity, climate, and geology(More)
Here we provide global estimates of the seasonal flux of sediment, on a river-by-river basis, under modern and prehuman conditions. Humans have simultaneously increased the sediment transport by global rivers through soil erosion (by 2.3 +/- 0.6 billion metric tons per year), yet reduced the flux of sediment reaching the world's coasts (by 1.4 +/- 0.3(More)
Hyperpycnal flows form in the marine environment when river discharge enters the ocean with suspended concentrations in excess of 36 kg m due to buoyancy considerations, or as little as 1–5 kg m when convective instability is considered. They form at a river mouth during floods of small to medium size rivers including extreme events such as jökulhaups, dam(More)
A new model for predicting the long-term flux of sediment from river basins to the coastal ocean is applied to a global data set of 340 river basins. The model is based on relief, basin area (or, averaged discharge), and basin-averaged temperature. Basinaveraged temperature is determined from basin location (latitude, longitude) and the lapse rate across(More)
Human activity is leaving a pervasive and persistent signature on Earth. Vigorous debate continues about whether this warrants recognition as a new geologic time unit known as the Anthropocene. We review anthropogenic markers of functional changes in the Earth system through the stratigraphic record. The appearance of manufactured materials in sediments,(More)
Correlations between suspended sediment load rating parameters, river basin morphology, and climate provide information about the physical controls on the sediment load in rivers and are used to create predictive equations for the sediment rating parameters. Long-term time-averaged values of discharge, suspended load, flow duration, flow peakedness, and(More)
The collapse of the Bronze Age Harappan, one of the earliest urban civilizations, remains an enigma. Urbanism flourished in the western region of the Indo-Gangetic Plain for approximately 600 y, but since approximately 3,900 y ago, the total settled area and settlement sizes declined, many sites were abandoned, and a significant shift in site numbers and(More)
We analyze 4000-year flood history of the lower Yellow River and the history of agricultural development in the middle river by investigating historical writings and quantitative time series data of environmental changes in the river basin. Flood dynamics are characterized by positive feedback loops, critical thresholds of natural processes, and abrupt(More)
The Reservoir Sedimentation Survey Information System (RESIS) is one of the world’s most comprehensive databases of reservoir sedimentation rates, comprising nearly 6000 surveys for 1819 reservoirs across the continental United States. Sediment surveys in the database date from 1904 to 1999, though more than 95% of surveys were entered prior to 1980, making(More)