The Eastern Sahara (Fig. i) is devoid of surface drainage -this unusual characteristic distinguishes its morphology from that of most other desert regions where running water dominates landscape development (Peel, 1939). Cyclic aridity, which is responsible for the obscuring eolian blankets and wind-erosion effects, had set in by the Pliocene-Pleistocene transition, about 2 million years ago (W...

This technical note describes a method for verifying the representativeness of mean-value and extreme-value water quality monitoring locations. Recommended techniques are illustrated using data collected with the total dissolved gas monitoring system on the Columbia and Snake Rivers. This technical note shows how statistical techniques can be applied to the design of monitoring systems to ensur...

There is now widespread agreement that the surface of Mars underwent some degree of fluvial modification, but there is not yet full understanding of its surface hydrological cycle and the nature of standing bodies of water, rivers, and precipitation that affected its surface. In this paper we explore Erythraea Fossa (31.5 W, 27.3 S), a graben adjacent to Holden crater, which exhibits strong evi...

We introduce a new PDE free boundary problem that in a singular limit admits an interesting metaphoric interpretation, describing how “water” originating from “rainfall” flows along a landscape of varying height, forming “lakes” and also “rivers” and “surface flows”, the latter described by transport equations along downhill gradient flows.

4. Observations and Projections: Cryosphere, Ocean Dynamics, and Hydrology Introduction 4.1 The Cryosphere 4.1.1 Antarctica 4.1.2 Greenland and Eurasian Ice Caps 4.1.3 Montane Glaciers 4.1.4 Sea and Lake Ice 4.2 Ocean Dynamics 4.2.1 Sea Level Change 4.2.2 Ocean Heat 4.2.3 Ocean Circulation 4.2.4 Africa 4.2.5 South America 4.2.6 Antarctica 4.2.7 Northern Hemisphere 4.2.8 Miscellaneous 4.3 Precip...

Rivers sourced in the Himalayan mountain range carry some of the largest sediment loads on the planet, yet coarse gravel in these rivers vanishes within approximately 10-40 kilometres on entering the Ganga Plain (the part of the North Indian River Plain containing the Ganges River). Understanding the fate of gravel is important for forecasting the response of rivers to large influxes of sedimen...

Sampling of whitebait from the migrations in a series of West Coast and Southland rivers (Heaphy, Orowaiti, Buller, Hokitika, Wanganui, Okarito, Mataura) showed that whitebait of the giant kokopu migrate late in the spring, beginning to enter rivers during early November and continuing well through December. Amongst 70 whitebait samples containing nearly 9000 whitebait there were only 231 giant...

Biological uptake of dissolved silicate (DSi) and formation of biogenic silica (BSi) during diatom growth modifies the form of Si carried from the continents to the world ocean. Significant concentrations of BSi, averaging 28.0 pmol L-l, are found in all sizes of rivers. The global contribution of BSi carried by rivers was estimated as 1.05 ? 0.20 Tmol Si year’. Combined with the global mean ri...

Amazon, 21, 24, 378–379 overbank, crevasses processes, 25 physical and biogeochemical processes, 92 plume dispersals, 55 sediment accumulation rates, 91 subaqueous delta clinoform system, 91–96 tidal-regime changes, sediment dynamics model, 92–94 Arctic Ocean, riverine organic and inorganic carbon fluxes, processing, fate acids to aldehydes ratios, 534–535 aragonite undersaturation, 542–543 Arc...

We present a new method for the realistic real-time simulation of rivers. Our solution includes a 2D fluid solver that simulates the flow of a river’s surface, an efficient method for adaptively computing 3D flow information and an animated 3D procedural wave texture that is advected through the fluid via advection particles in order to mimic the highly detailed fluid surfaces that are characte...