We present the isotopic composition of meltwater samples from four seasonal snowpacks: a warm, maritime snowpack in California; a temperate continental snowpack in Vermont; a cold continental snowpack in Colorado; and an Arctic snowpack in Alaska. Despite the very different climate conditions the υ18O of meltwater from all four snowpacks increased as melting progressed. This trend is consistent...

Stream water samples were collected over a range of hydrologic and seasonal conditions at three forested watersheds in the northeastern USA. Samples were analyzed for dissolved total mercury (THg(d)), DOC concentration and DOC composition, and UV(254) absorbance across the three sites over different seasons and flow conditions. Pooling data from all sites, we found a strong positive correlation...

The prediction uncertainty of a hydrologic model is closely related to model formulation and the uncertainties in model parameters and inputs. Currently, the foremost challenges concern not only whether hydrologic model outputs match observations, but also whether or not model predictions are meaningful and useful in the contexts of land use and climate change. The latter is difficult to determ...

Simulation of flow hydrograph at an ungauged site recently has attracted considerable attention. A distributed rainfall-runoff model not only can describe the spatial heterogeneity of physiographical and hydrological characteristics in the catchment, but also can simulate the hydrological processes inside the studied area. If a distributed rainfall-runoff model can be adequately verified based ...

The basic principles underlying the most commonly used physically-based models of the rainfall-runoff transformation process are reviewed. A thorough knowledge of these principles is a pre-requisite for flood hazard studies and, thus, this chapter reviews several physically-based methods to determine flood discharges, flow depths, and other flood characteristics. The chapter starts with a thoro...

Here we report on three years (1996-1998) of measurements of organic and inorganic nitrogen (N) fluxes to and from Green Lakes Valley, a high-elevation ecosystem in the Colorado Front Range of the Rocky Mountains. Nitrate-N (NO3−N) was the dominant form of N in both precipitation and streamwater. Annual precipitation contained 52% NO3−N, 32% ammonium-N (NH4−N), 9% dissolved organic N (DON), and...